Mechanistic Basic to Clinical
3278 Gendered racism, psychological distress, and the strong Black woman
- Maha Baalbaki
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- 26 March 2019, p. 107
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OBJECTIVES/SPECIFIC AIMS: Black women experience discrimination that targets their intersecting gender and ethnic identities, termed gendered racism (Essed, 1991). The gendered racism Black women experience has been linked to negative mental health outcomes (Thomas etal., 2008). The ‘strong Black woman’ is a cultural symbol of strength depicting the Black woman as unwavered by hardships, such as gendered racism (Shorter-Gooden & Washington, 1996). However, recent research suggests that belief in the strong Black woman cultural construct is associated with negative mental health outcomes (Watson & Hunter, 2015). The goals of the current study were to (1) replicate previous findings suggesting that experiences with gendered racism is positively correlated with psychological distress, (2) replicate previous findings suggesting that belief in the strong Black woman construct is positively correlated with psychological distress, and (3) explore how experiences with gendered racism and belief in the strong Black woman construct might interact to predict distress. METHODS/STUDY POPULATION: A national sample of 112 Black women completed an online survey via MTurk. Survey measures included the Gendered Racial Microaggressions Scale, Strong Black Woman Cultural Construct Scale, and Psychological Distress Scale. RESULTS/ANTICIPATED RESULTS: Pearson correlation revealed that experiences with gendered racism was positively correlated with psychological distress, r = 0.23, p = .02. Pearson correlation also revealed that belief in the strong Black woman cultural construct was positively correlated with psychological distress, r = 0.39, p < .001. Multiple linear regression revealed an interaction between experiences with gendered racism and belief in the strong Black woman construct (β = -0.18, p = .04) that predicted psychological distress, R2 = .20, F(3,108) = 8.63, p < .01. Namely, for those with high belief in the strong Black woman construct, experiences with gendered racism did not predict distress, β = -0.31, t = -0.29, p = .78. However, for those with low belief in the construct, experiences with gendered racism positively predicted distress, β = -2.57, t = 2.31, p = .02. DISCUSSION/SIGNIFICANCE OF IMPACT: The results underscore the harmful effects of gendered racism and gendered racial stereotypes on Black women’s mental health outcomes. Striving to appear as the strong Black woman is not likely to help Black women overcome daily hardships. In fact, belief in the strong Black woman construct is likely to add extra difficulties.
3477 Impaired emotion recognition accuracy after right-hemisphere stroke
- Katherine OConnell, Abigail A. Marsh, Anna Greenwald
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- 26 March 2019, p. 108
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OBJECTIVES/SPECIFIC AIMS: Every year, approximately 800,000 Americans suffer a stroke. Supportive social environments are recognized as an important factor contributing to successful stroke recovery, yet, stroke lesions can affect brain areas important for socioemotional functioning, which could impair a patient’s ability to maintain their social relationships. Specifically, emotion recognition, a fundamental socioemotional skill, is predominantly right-lateralized and may be impacted by right-hemisphere stroke. This research tests for emotion recognition impairments after right-hemisphere stroke and examines whether such deficits are associated with worse reported social support. METHODS/STUDY POPULATION: Twenty right-hemisphere stroke patients (9 female, 11 male) and 23 age-matched healthy control subjects (9 female, 14 male) completed laboratory testing including the Geneva Emotion Recognition Test Short. Subjects additionally completed a measure of self-reported social support using the Older Americans Resources and Services questionnaire. Emotion recognition accuracy was calculated using overall accuracy and valence accuracy (i.e. correctly rating a positive emotion as positive). RESULTS/ANTICIPATED RESULTS: Right-hemisphere stroke patients had lower overall emotion recognition accuracy than controls (patients; M = 37.8%, SD = 18.9%. controls; M = 48.5%, SD = 14.6%, t(41)=2.11, p=.041). Furthermore, patients had significantly lower valence accuracy (patients; M = 84.5%, SD = 10.7%. controls; M = 90.0%, SD = 5.2%, t(41)=2.19, p =.035), indicating that they more often mistook a positive emotion as a negative emotion, and vice-versa. Finally, within the right-hemisphere patient group, overall emotion recognition accuracy was trending to be positively correlated with self-reported social support (rho = 0.397, p =.083), suggesting that poor emotion recognition skills may be associated with worse social outcomes in the real-world. DISCUSSION/SIGNIFICANCE OF IMPACT: Our findings indicate that right-hemisphere stroke is associated with impaired emotion recognition. Future research could investigate whether an emotion recognition training may be beneficial for right-hemisphere stroke patient recovery.
3323 Juvenile Polyposis Syndrome Patients Without a Mutation in SMAD4 or BMPR1A: Clinical Presentation and Novel Drivers of Disease
- Suzanne MacFarland, Jessica Ebrahimzadeh, Kristin Zelley, Petar Mamula, Garrett Brodeur, Bryson Katona
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- 26 March 2019, p. 108
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OBJECTIVES/SPECIFIC AIMS: Juvenile Polyposis Syndrome (JPS) is an inherited cancer predisposition syndrome sometimes attributed to a germline mutation in SMAD4 or BMPR1A. However, many patients meet clinical criteria for JPS without having a pathogenic alteration in either gene. Herein, we perform a cross-sectional analysis of JPS patients at a pediatric and adult tertiary referral center to understand potential differences in the clinical presentation and outcomes of patients with or without a known causative gene mutation. Additionally, we conduct whole exome sequencing (WES) on a subset of the pediatric patients to evaluate for novel genomic drivers of disease. METHODS/STUDY POPULATION: Data were abstracted from medical charts using IRB-approved protocols at the Children’s Hospital of Philadelphia (CHOP) and the University of Pennsylvania (Penn). Records were reviewed for patients with a clinical diagnosis of JPS and genetic testing result and seen at either institution in the last 10 years (2008-2018). Patients recruited for sequencing were consented for blood draw through the CHOP IRB protocol, and had whole exome sequencing completed at 70X depth, with data analyzed through institutional pipeline. RESULTS/ANTICIPATED RESULTS: Records were reviewed for 41 patients at CHOP and 19 patients at Penn, for a total of 60 JPS patients. Mean age of CHOP cohort was 11 years: 58.5% male, mean length of follow up 3.9 years. Mean age Penn cohort was 33 years: 47.4% male, mean length of follow up 9.3 years. In the pediatric cohort, 7 patients (17%) had a mutation in BMPR1A (n=6) or SMAD4 (n=1); in the adult cohort, 15 patients (79%) had a mutation in BMPR1A (n=3) or SMAD4 (n=12). The average number of polyps in the pediatric cohort was not significantly higher in patients with a SMAD4 or BMPR1A mutation (9.3 polyps/year of surveillance with a SMAD4 or BMPR1A mutation, vs 5.7 polyps/year; p=0.19). In combined cohort review, all individuals that required gastrectomy and/or colectomy (n=8) as well as all those who developed gastrointestinal cancer (n=3) had a mutation in SMAD4 or BMPR1A. Of the patients who underwent whole exome sequencing (n=13), potential causative germline mutations were identified in four patients (30.8%); all potential drivers identified were within the TNF/BMP pathway. DISCUSSION/SIGNIFICANCE OF IMPACT: This data from a dual-institution review demonstrates that the rate of SMAD4/BMPR1A mutation in JPS is lower in a pediatric cohort compared to an adult cohort. Furthermore, although individuals with JPS may have similar clinical presentations in childhood regardless of whether or not a causative mutation is present, the presence of a mutation in SMAD4 or BMPR1A is associated with a more severe course of disease in adulthood. Further study and a larger cohort will be required to fully validate these findings. Approximately 30% of patients who underwent germline WES had a potential novel driver identified, with further validation underway.
3122 Longitudinal Recovery of Speech Motor Function Following Facial Transplantation
- Bridget Jane Perry, Kaila Stipancic, Brian Richburg, Jordan Green
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- 26 March 2019, pp. 108-109
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OBJECTIVES/SPECIFIC AIMS: Using a novel biomechanical-based motor speech assessment alongside commonly used clinically-based motor speech assessments, the goal of this study was to describe longitudinal recovery in speech movements and functional speech in a cohort of 5 patients following facial transplantation. METHODS/STUDY POPULATION: Five participants who had received either full or partial face transplantation were included in this study. Each participant received a unique facial graft from their donor, which included varied amounts of soft tissue, facial musculature, nerve, and bone. Two participants were early in the recovery period and were assessed from zero to 24 months post-transplantation. Three participants were late in the recovery period and were assessed from 36 to 60 months post-transplantation. Each participant completed two data collection sessions and the average time between sessions was 20.4 months. At each session, orofacial movements were recorded using a 3D motion capture system. A 4-sensor head marker was used to subtract head movement (translation and rotation) from the facial markers. The analyses in this study were restricted to two markers: midline lower lip and a virtually calculated midline jaw marker. A marker at the top of the nose bridge was used as the origin point. The following kinematic variables were obtained from each lip-jaw movement time-series: peak movement speed (mm/s), and displacement (mm). Each patient was instructed to perform 10 repetitions of the phrase “buy bobby a puppy” at his or her typical speaking rate and volume. Sentence-level intelligibility was obtained using the Sentence Intelligibility Test (SIT) and word-level intelligibility was obtained using the Word Intelligibility Test, using standard procedures. Intelligibility, measured in percentage of words correctly transcribed, and speaking rate, measured in words per minute (wpm), was derived from the SIT sentences for each patient. Intelligibility, measured in percentage of words correctly chosen via multiple choice was derived from the Word Intelligibility Test. RESULTS/ANTICIPATED RESULTS: Effect sizes (Cohen’s d) across the 10 trials of “buy bobby a puppy” were computed to assess the effects of recovery time on range of motion and speed of the lower lip alone, the jaw alone, and the lower lip and jaw together for both range of motion and for speed. The largest effect sizes were observed for increased range of motion and increased speed of the articulators for participants within 24 months of surgery. Smaller effect sizes were observed for these parameters for the participants in the later stages of recovery, with some participants showing declines in range of motion and speed of some but not all articulators. Descriptive statistics indicate that both speech and word intelligibility improvements are most notable in the first two years following transplantation and appear to plateau during the later stages of recovery. Only two out of five of our participants achieved “normal” speech intelligibility (i.e., >97%) at five years post-transplantation. DISCUSSION/SIGNIFICANCE OF IMPACT: Biomechanical assessment revealed that kinematic recovery of articulator range of motion and speed appears most significant in the first two years following surgery, but that improvement continues to some degree as far as five-years post-transplant. Clinically-based assessments suggest that gains in intelligibility appear to plateau by 3-years post-surgery.
3559 Mechanisms of sebaceous skin microbial community remodeling through microenvironment modulation.
- William Howard McCoy IV, Bruce Rosa, John Martin, Makedonka Mitreva, Jeffrey P. Henderson
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- 26 March 2019, p. 109
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OBJECTIVES/SPECIFIC AIMS: To understand the mechanisms of how a non-antimicrobial can reshape a commensal microbe community to cure a ubiquitous human disease. METHODS/STUDY POPULATION: Whole genome sequencing of bacterial isolates, metabolomic investigations of previously collected skin microbe isolates from patients, and structural investigations of a protein from these skin microbes. RESULTS/ANTICIPATED RESULTS: Metabolic pathways associated with adaptation to a changing skin microenvironment, novel antimicrobial characterization, and a structural understanding of a novel nutrient acquisition protein. DISCUSSION/SIGNIFICANCE OF IMPACT: Multiple angles of this investigation are poised to improve current non-antimicrobial dermatologic treatments and they have the potential to impact microbe-related diseases in other human microenvironments.
3496 Mesenchymal Stem Cell Extracellular Vesicle Delivery in a Shear-Thinning Hydrogel For Therapy in an Acute Myocardial Infarction Model: A Comparative Analysis
- Drew Goldberg, Ann Gaffey, Minna Chen, Elizabeth Li, Samuel Kim, Zoe Tran, Jason Burdick, Pavan Atluri
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- 26 March 2019, p. 109
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OBJECTIVES/SPECIFIC AIMS: The primary aim is to assess differences in therapeutic effect between MSC and EPC EVs on acute ischemic rat hearts through delivery in a biocompatible and shear-thinning hydrogel. Primary outcomes for therapeutic assessment include an in-vitro angiogenesis assay and in-vivo hemodynamic analysis, mainly identifying differences in ejection fraction and contractility. Secondary hemodynamic outcomes include cardiac output, stroke volume, and end-diastolic pressure volume relationship (EDPVR). Secondary structural outcomes include post-mortem scar analysis and immunohistochemistry (IHC) staining for angiomyogenesis. METHODS/STUDY POPULATION: MSCs and EPCs will be cultured according to previously published protocols. EVs will be isolated from cultured cell lines through precipitation methods with polyethylene glycol. EVs will be qualitatively analyzed with nanoparticle tracking analysis (NTA) and flow cytometry. The shear thinning hydrogel (STG) will be constructed using a hyaluronic backbone conjugated to adamantane or beta-cyclodextrin, ultimately facilitating guest-host interactions with shear thinning properties. Controls and treatment groups mixed with the hydrogel will be injected into the border zone of infarcted Wistar rat hearts immediately following a left anterior descending artery ligation. Hemodynamic assessment will be performed at four weeks through left ventricular catheter based pressure-volume recordings. Ex-vivo analysis will include scar thickness assessment using Masson collagen staining and IHC stain for vessel (anti-vonWillebrand factor; anti-Isolectin) and myocyte formation (anti-cardiac Troponin I). RESULTS/ANTICIPATED RESULTS: We hypothesize that, in-vitro, MSC-EVs will demonstrate non-inferior angiogenic potential as compared to EPC-EVs. We posit that MSC-EVs will demonstrate superior therapeutic effect to EPC-EVs in-vivo as measured by functional hemodynamics and structural assessment. We have successfully isolated MSC and EPC EVs and have validated uniformity across EV populations (Figure 1). Preliminary data from the angiogenesis assay (n=3) demonstrated that MSC-EV and EPC-EV produce non-significantly different angiogenic potential as measured by number of vascular meshing extremes (p=0.144) and length of master vascular segment (p=0.193), with significant differences compared to either positive or negative controls. DISCUSSION/SIGNIFICANCE OF IMPACT: Novel regenerative therapies are needed for patients with a history of AMI given current limitations to therapy and sequelae of ischemic heart disease. Delivery of extracellular vesicles through a shear-thinning gel is a novel “off-the-shelf” translational approach to address the current clinical need.
3019 Metabolomic Markers of Methotrexate Response in Juvenile Idiopathic Arthritis
- Ryan Sol Funk, Mara Becker
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- 26 March 2019, pp. 109-110
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OBJECTIVES/SPECIFIC AIMS: In this study, a semi-targeted metabolomics approach is used to identify metabolic markers of methotrexate (MTX) response in juvenile idiopathic arthritis (JIA) and in vitro. METHODS/STUDY POPULATION: A comparative metabolomic analysis was used to identify metabolomic markers and metabolic pathways associated with MTX activity in vitro and in vivo. Cell-based studies assessed metabolomic profiles in K562 erythroblastoid cells with or without MTX treatment. In vivo analysis utilized plasma samples from JIA patients treated with MTX (n=30) and included samples collected prior to the initiation of MTX and after 3-months of MTX treatment. Plasma samples were from an IRB-approved single center prospective cohort study of biomarkers of MTX response in patients with JIA and were stratified based on American College of Rheumatology pediatric (ACR Pedi) response criteria. Semi-targeted global metabolomic profiles including over 800 metabolites across three analytical platforms at the NIH West Coast Metabolomics Center at UC-Davis and were analyzed by univariate and multivariate analysis using MetaboAnalyst 3.0. RESULTS/ANTICIPATED RESULTS: In K562 cells, MTX treatment was associated with statistically significant changes in 550 of the 850 intracellular metabolites detected (false discovery rate less than 0.05). Major metabolic pathways inhibited by MTX included branched-chain amino acid metabolism, purine and pyrimidine biosynthesis, and lipid metabolism including the inhibition of arachidonic acid metabolism. In patients with JIA, far fewer plasma metabolites were significantly altered following the initiation of MTX and included only 15 of the 833 plasma metabolites detected. Interestingly, MTX treatment was associated with the inhibition of arachidonic acid synthesis, inhibition of purine metabolism, and a dramatic reduction in plasma levels of various exogenous metabolites. In particular, MTX treatment was associated reductions in known metabolic markers of intestinal microbiota metabolism, including: biotin and dehydrocholic acid. Further, stratification of patients based on ACR Pedi response demonstrated that clinical response was associated with a greater reduction in plasma dehydrocholic acid levels following the initiation of MTX. DISCUSSION/SIGNIFICANCE OF IMPACT: This work demonstrates that MTX therapy is associated with a number of biochemical changes in vitro and in vivo, including: inhibition of purine metabolism, inhibition of arachidonic acid metabolism, and an apparent inhibition of gut microbiota metabolism. Most notably, inhibition of gut microbiota metabolism appears to demonstrate a relationship with the observed clinical efficacy of MTX in JIA.
3280 Mycobacterium bovis Bacille-Calmette-Guérin infection aggravates atherosclerosis
- Moises Huaman, Joseph E. Qualls, David Kuhel, Shinsmon Jose, Eddy Konaniah, Ravi Komaravolu, Carl J. Fichtenbaum, George S. Deepe, Jr., David Y. Hui
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- 26 March 2019, p. 110
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OBJECTIVES/SPECIFIC AIMS: The study aimed at assessing whether M. bovis BCG infection and inflammation exacerbates the development of atherosclerosis in Ldlr-/- mice. METHODS/STUDY POPULATION: Twelve-week old male Ldlr-/- mice (n=10) were infected with M. bovis BCG (0.3–3.0x10^6 colony-forming units (CFUs)) via the intranasal route, to simulate a natural respiratory route of infection. Mice were subsequently fed a western-type diet (WD) containing 21% fat and 0.2% cholesterol for 16 weeks. Age-matched uninfected Ldlr-/- mice (n=10) fed with an identical WD served as controls. Mice were euthanized after 16 weeks of WD to examine atherosclerotic lesions in aortic root sections and en face aorta using Oil Red O staining. Plasma cholesterol and triglyceride levels were measured by enzymatic assays and lipoprotein distribution was assessed using fast protein liquid chromatography. Because of the important role of T cells and monocytes in atherosclerosis development, we assessed these cell subsets in blood using flow cytometry at 8 and 16 weeks. Experiments were conducted in duplicate. We used unpaired Student’s t-test for group comparisons of numeric variables and flow cytometry data. RESULTS/ANTICIPATED RESULTS: M. bovis BCG infection significantly increased atherosclerotic lesions in en face aorta (plaque size per aorta area ratio; 0.15±0.13 vs. 0.06±0.02; P<0.01), but not in the aortic root. There were no significant differences in plasma cholesterol (1,160 mg/dL vs. 1,278 mg/dL; P = 0.36), triglycerides (340 mg/dL vs. 413 mg/dL; P = 0.28), or lipoprotein profiles between infected vs. uninfected mice at 16 weeks. M. bovis BCG increased circulating T lymphocytes (1,490 cells/uL vs. 1,227 cells/uL; P = 0.03) and monocytes (901 cells/uL vs. 414 cells/uL; P<0.01) within 8 weeks post-infection. When we assessed T lymphocyte subsets, M. bovis BCG infection increased total CD4+ T cell counts (556 cells/uL vs. 416 cells/uL; P<0.01) but not CD8+ T cells. No differences in the proportion of CD44+CD25+ activated T lymphocytes were noted between groups. When we assessed monocyte subsets, M. bovis BCG infection increased the numbers of Ly6Chigh (709 cells/uL vs. 362 cells/uL; P<0.01) and Ly6Clow (145 cells/uL vs. 35 cells/uL; P<0.01) monocytes. Infection was associated with an increased proportion of Ly6Clow monocytes at week 8 (17% vs. 8%; P<0.01) and week 16 (19% vs. 5%; P<0.01), compared to uninfected mice. DISCUSSION/SIGNIFICANCE OF IMPACT: M. bovis BCG infection increased the extent of atherosclerosis formation in the aortas of WD-fed hyperlipidemic Ldlr-/- mice after 16 weeks. Lipid profiles were similar between infected and uninfected mice, and therefore do not explain the observed differences in atherosclerosis. Compared to uninfected controls, M. bovis BCG-infected mice exhibited increased CD4+ T cell and monocyte driven inflammation. Interestingly, M. bovis BCG-infected mice had a higher proportion of non-classical Ly6Clow monocytes, suggesting a pro-atherogenic contribution of these cells in our model. Overall, our results support a pathogenic role of mycobacterial infection in atherosclerosis development and ASCVD.
3000 Olfactory habituation in schizophrenia
- Patricia Estani
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- 26 March 2019, p. 110
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OBJECTIVES/SPECIFIC AIMS: The aim objective of this research work is the study of neurocognitive endophenotypes in the new classifications of mental disorders. METHODS/STUDY POPULATION: Neuropsychological tests,such as the UPSIT test were used. The population was composed by a sample of patients with a diagnosis of schizophrenia RESULTS/ANTICIPATED RESULTS: Olfactory discrimination is a potencial neurocognitive endophenotype in the study of schizophrenia research DISCUSSION/SIGNIFICANCE OF IMPACT: The aim impact of this research work is the study of Dimensional classifications of mental disorders.
3131 ONCOSTREAMS: NOVEL DYNAMICS PATHOLOGICAL MULTICELLULAR STRUCTURES INVOLVED IN GLIOBLATOMA GROWTH AND INVASION
- Andrea Comba, Patrick Dunn, Anna E Argento, Padma Kadiyala, Sebastien Motsch, Phillip Kish, Alon Kahana, Daniel Zamler, Karin Muraszko, Maria G Castro, Pedro R Lowenstein
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- 26 March 2019, p. 111
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OBJECTIVES/SPECIFIC AIMS: Oncostreams represent a novel growth pattern of GBM. In this study we uncovered the cellular and molecular mechanism that regulates the oncostreams function in GBM growth and invasion. METHODS/STUDY POPULATION: We studied oncostreams organization and function using genetically engineered mouse gliomas models (GEMM), mouse primary patient derived GBM model and human glioma biopsies. We evaluated the molecular landscape of oncostreams by laser capture microdissection (LCM) followed by RNA-Sequencing and bioinformatics analysis. RESULTS/ANTICIPATED RESULTS: Oncostreams are multicellular structures of 10-20 cells wide and 2-400 μm long. They are distributed throughout the tumors in mouse and human GBM. Oncostreams are heterogeneous structures positive for GFAP, Nestin, Olig2 and Iba1 cells and negative for Neurofilament. Using GEMM we found a negative correlation between oncostream density and animal survival. Moreover, examination of patient’s glioma biopsies evidenced that oncostreams are present in high grade but no in low grade gliomas. This suggests that oncostreams may play a role in tumor malignancy. Our data also indicated that oncostreams aid local invasion of normal brain. Transcriptome analysis of oncostreams revealed 43 differentially expressed (DE) genes. Functional enrichment analysis of DE genes showed that “collagen catabolic processes”, “positive regulation of cell migration”, and “extracellular matrix organization” were the most over-represented GO biological process. Network analysis indicated that Col1a1, ACTA2, MMP9 and MMP10 are primary target genes. These genes were also overexpressed in more malignant tumors (WT-IDH) compared to the less malignant (IDH1- R132H) tumors. Confocal time lapse imagining of 3D tumor slices demonstrated that oncostreams display a collective motion pattern within gliomas that has not been seen before. DISCUSSION/SIGNIFICANCE OF IMPACT: In summary, oncostreams are anatomically and molecularly distinctive, regulate glioma growth and invasion, display collective motion and are regulated by the extracellular matrix. We propose oncostreams as novel pathological markers valuable for diagnosis, prognosis and designing therapeutics for GBM patients.
3024 Osteocyte-derived CXCL12 is Essential for Load-Induced Bone Formation in Adult Mice
- Pamela Cabahug Zuckerman, Chao Liu, Emily Fang, Alesha B Castillo
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- 26 March 2019, p. 111
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OBJECTIVES/SPECIFIC AIMS: Our aim is to test whether osteocyte-specific CXCL12 expression is critical to exercise-driven bone formation. METHODS/STUDY POPULATION: All procedures were approved by the NEW YORK UNIVERSITY Institutional Animal Care and Use Committee. We generated male and female mice in which CXCL12 was deleted from OCYs (CXCL12ΔOCY) by crossing CXCL12 floxed mice and 10kb DMP1-Cre transgenic mice (gifts from Drs. Geoffrey Gurtner and Lynda Bonewald, respectively). The 10kb DMP1-Cre has been shown to be robustly expressed in odontoblasts and OCYs, with little to no activity in cells from non-mineralized tissues (Lu+ J Dent Res 2007). Growing male and female mice (n=3-8/group) were given fluorochrome labels every two weeks between 4-16 weeks of age, to monitor the role of CXCL12 during development. A second group, of adult 16-week-old mice (n=5/group), were subjected to tibial axial cyclic loading (1200µɛ, 2Hz, 120cycles, 3days/wk for 2 wks) (Liu+ Bone 2018). Basal and load-induced periosteal (Ps) and endosteal (Es) mineralizing surface (MS/BS, %), mineral apposition (MAR, µm/day) and bone formation rates (BFR/BS, µm3/µm2/year) were calculated (Dempster+ JBMR.2013) at mid-length. RESULTS/ANTICIPATED RESULTS: No significant differences were detected in basal bone formation during development. However, relative load-induced Ps MAR (rMAR) was reduced by 50% in female (p=0.02) and 75% in male (p=0.002) CXCL12ΔOCY mice; and similarly, Ps rBFR/BS was reduced by 50% in female (p=0.01) and 70% in male (p=0.001) CXCL12ΔOCY mice (Figure 1). Es bone formation was not affected by CXCL12 deletion. DISCUSSION/SIGNIFICANCE OF IMPACT: In summary, osteocyte-specific CXCL12 expression plays a critical role in exercise-driven periosteal new bone formation, suggesting that CXCL12 signaling may positively regulate osteogenic differentiation and/or mature osteoblast function. Further underlying mechanisms are currently being explored. Thus, osteocyte-specific CXCL12 signaling may be a promising target to enhance load-induced bone formation in patients with compromised ability to form new bone.
3332 Overexpression of CD44 is involved in the development of the early endometriotic lesion in a xenograft model
- Jennifer Knudtson, Jessica McLaughlin, Marlen Tellez Santos, Rajeshwar R Tekmal, Robert Schenken
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- 26 March 2019, pp. 111-112
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OBJECTIVES/SPECIFIC AIMS: Previously, we showed decreased development of endometriotic lesions in CD44 knockout mice compared to control.(1) CD44 has 10 different variants and a standard form. Menstrual endometrial cells (MECs) from women with endometriosis have increased adhesion and also express higher levels of CD44 variant 6 (v6) than v3, compared to MECs from women without endometriosis. (2) Here, we assessed the effects of CD44 standard (CD44s), CD44v3 and CD44v6 overexpression (OE) on immortalized human endometrial epithelial (iEECs) and stroma cells (hESCs) in vivo attachment in a nude mouse xenograft model. 1. Knudtson JF, Tekmal RR, Santos MT, et al. Impaired Development of Early Endometriotic Lesions in CD44 Knockout Mice. Reproductive sciences (Thousand Oaks, Calif.). 2016;23(1):87-91. 2. Griffith JS, Liu YG, Tekmal RR, Binkley PA, Holden AE, Schenken RS. Menstrual endometrial cells from women with endometriosis demonstrate increased adherence to peritoneal cells and increased expression of CD44 splice variants. Fertility and sterility. 2010;93(6):1745-1749. METHODS/STUDY POPULATION: Overexpression of CD44s, CD44v3 and CD44v6 was carried out using lipofectamine and their expression verified with qRT-PCR in iEEC and hESCs. Nude mice, 8-10 week old, were injected with estrogen 1 week prior to injection of iEECs and hESCs (n=7 per group). The cells were counted after transfection and at least 300,000 iEECs and 300,000 hESCs were injected per mouse. The transfected cells were tagged with cell tracker red (iEECs) and green (hESCs). Forty-eight hours after injection into the xenograft, the mice were sacrificed. The cells were counted using fluorescent stereo microscopy (FSM). Percent attachment was calculated based on the number of cells visualized by FSM divided by the number of transfected cells injected. Unpaired student t-test was performed to analyze differences in the percent attachment of the cells. RESULTS/ANTICIPATED RESULTS: The majority of cells were attached to the peritoneum. There was increased attachment of hESCs with OE of CD44v6 compared to control (p=0.03). CD44v6 OE did not change attachment of iEECs. There was no difference in attachment in iEECs or hESCs with OE of CD44s or CD44v3. DISCUSSION/SIGNIFICANCE OF IMPACT: Overexpression of CD44v6 increases attachment of ESCs to PMCs in an in vivo xenograft model. Menstrual endometrial cell type and CD44 variants play a complex role in the development of the early endometriotic lesion.
3468 Predictive biomarkers of platinum-based chemotherapy response in Puerto Rican Hispanics with high-grade serous ovarian cancer.
- Jeyshka M. Reyes-Gonzalez, Sharee Umpierre, Pablo E. Vivas-Mejia
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- 26 March 2019, p. 112
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OBJECTIVES/SPECIFIC AIMS: High-grade serous ovarian carcinoma (HGSOC) is the most common and malignant histological subtype of epithelial ovarian cancer. While the majority of HGSOC patients initially respond to platinum-based chemotherapy, they often present with recurrent chemoresistant disease, which is extremely fatal. Therefore, there is an urgent need to identify predictive biomarkers of platinum response and to develop rational, targeted therapies to improve the outcome of patients with HGSOC. The objectives of the present study are to profile and assess the clinical significance of MYC network dysregulation in HGSOC. METHODS/STUDY POPULATION: We will conduct a retrospective cohort study of Puerto Rican Hispanics with HGSOC who underwent surgery followed by platinum-based chemotherapy at clinical institutions in Puerto Rico. Medical records, pathology reports, and cancer registries will be reviewed to extract data on clinicopathological features, disease recurrence, and death. For eligible patients, formalin-fixed, paraffin-embedded (FFPE) tissue samples will be processed and analyzed by quantitative Real Time PCR (qRT-PCR) and immunohistochemistry (IHC). RESULTS/ANTICIPATED RESULTS: Expression levels of MYC and MYC-related molecules are expected to correlate with clinicopathological features and prognosis of HGSOC. DISCUSSION/SIGNIFICANCE OF IMPACT: The identification and validation of clinically-relevant alterations in HGSOC, such as dysregulation of the MYC network, will be crucial to guide therapy regimen, maximize clinical benefit, and improve patient outcome.
3506 PRMT5 is a novel therapeutic target to enhance radiation therapy for cancer treatment
- Jake L Owens, Elena Beketova, Samantha Tinsley, Andrew Asberry, Xuehong Deng, Chang-Deng Hu
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- Published online by Cambridge University Press:
- 26 March 2019, p. 112
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OBJECTIVES/SPECIFIC AIMS: Prostate cancer is the second leading cause of cancer-related death among men in the U.S. and over half of all prostate cancer patients receive radiation therapy (RT). RT induces double-strand breaks (DSBs) in DNA which are lethal to cells if not repaired. While potentially curative, 10% of low-risk patients and 50% of high-risk patients treated with RT still experience tumor recurrence. Thus, identification of novel therapeutic targets to enhance RT will likely reduce prostate cancer mortality. The only clinical approach to enhance RT is androgen deprivation therapy, which targets androgen receptor (AR) signaling; however, its use is limited due to systemic side effects. We recently reported that PRMT5 epigenetically activates AR which led us to investigate if targeting PRMT5 sensitizes prostate cancer to RT. The goal of this project is to determine if PRMT5 is a therapeutic target for prostate cancer radiosensitization and analyze its mechanistic role in response to radiation. METHODS/STUDY POPULATION: To evaluate if targeting PRMT5 may sensitize prostate cancer cells to radiation, we performed a clonogenic assay of irradiated cells. To determine if PRMT5 is required for repair of radiation-induced DSBs, we performed foci analysis via immunocytochemistry. We then used RNA-seq, qPCR, western blot, and ChIP to evaluate a potential epigenetic role of PRMT5 in activating the expression of genes critical to DSB repair. To extend our findings, we analyzed clinical data from around 18,000 of cancer patients encompassing 43 cancer types to assess if PRMT5 expression correlates with the expression of its putative target genes. RESULTS/ANTICIPATED RESULTS: Targeting PRMT5 sensitizes prostate cancer cells to radiation independently of AR status. RNA-seq analysis revealed putative PRMT5 target genes including several involved in DSB repair and G2 arrest. Mechanistically, PRMT5 functions as a master epigenetic activator of DNA damage response (DDR) genes: PRMT5 maintains the basal expression of several DDR genes including BRCA1, BRCA2, and RAD51 and is recruited upon radiation to DDR gene promoters to activate their expression via histone methylation. Targeting PRMT5 decreases expression of these genes at the protein level and hinders repair of radiation-induced DSBs in multiple cancer and non-cancer cell types. Clinically, PRMT5 expression positively correlates with the expression of these DDR genes across all 43 cancer types analyzed. DISCUSSION/SIGNIFICANCE OF IMPACT: PRMT5 acts as a master epigenetic activator of genes involved in DDR and is critical for cells to survive radiation treatment. Importantly, PRMT5 epigenetically activates multiple genes that encode for well-characterized core repair proteins involved in HR (RAD51, RAD51AP1, RAD51D, BRCA1 and BRCA2) and NHEJ (NHEJ1, Ku80, XRCC4, and DNAPKcs), which may explain why PRMT5 is essential to repair IR-induced DSBs in several cell lines. As PRMT5 is overexpressed in many human cancers and its overexpression correlates with poor prognosis, our findings suggest that more efficient DSB repair via PRMT5 overexpression in these cancers may confer survival advantages particularly following DNA damaging treatments. Lastly, because targeting DSB repair is a clinically validated therapeutic approach for cancer treatment, our findings also suggest that PRMT5 targeting may be explored as a monotherapy or in combination therapy with radiation therapy or chemotherapy for cancer treatment.
3204 Renin-Angiotensin System Inhibitors Do Not Improve Survival in Fibrillin-1 Hypomorphic Mice with Established Aortic Aneurysm
- Mary Burchett Sheppard, Jeff Zheying Chen, Debra L. Rateri, Jessica J. Moorleghen, Mackenzie Weiland, Alan Daugherty
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- Published online by Cambridge University Press:
- 26 March 2019, pp. 112-113
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OBJECTIVES/SPECIFIC AIMS: Drugs to attenuate aortic growth are usually not initiated in patients with Marfan syndrome until aortic dilation is already present. Therefore, we measured the impact of drugs (the renin-angiotensin system inhibitors losartan and enalapril) on survival and thoracic aortic growth in a mouse model of Marfan syndrome when extensive aortic dilation was already present. METHODS/STUDY POPULATION: Male and female fibrillin-1 hypomorphic (FBN1 mgR/mgR) mice (n=10-12/group) were stratified into treatment groups by aortic diameter at 6 weeks of age to ensure an equivalent average aortic diameter in each group at the start of the study. Osmotic mini pumps filled with PBS (vehicle), enalapril (2 mg/kg/d), or losartan (20 mg/kg/d) were implanted subcutaneously into mice after stratification. Mini pumps infusing drug or vehicle were replaced every 4 weeks for a total duration of 12 weeks. Wild type littermates (n=10) were infused with PBS as a negative control to the Marfan mouse model. Ascending aortic diameters from male and female FBN1 mgR/mgR mice and their wild type littermates were assessed by ultrasound every 4 weeks from 6 to 18 weeks of age. Aortic diameters were measured luminal edge to luminal edge during diastole. RESULTS/ANTICIPATED RESULTS: 6 week old FBN1 mgR/mgR mice exhibited significantly dilated ascending thoracic aortas at study initiation compared to their wild type sex-matched littermates (in males: FBN1 mgR/mgR = 1.87 +/− 0.07mm, wild type = 1.23 +/− 0.07mm; p <0.001) (in females: FBN1 mgR/mgR = 1.56 +/− 0.07mm, wild type = 1.18 +/− 0.07mm; p <0.001). Baseline mortality of FBN1 mgR/mgR mice infused with PBS was 36% in male and 22% in female mice at the time of study termination. Within sex-matched mgR littermates, there was no significant difference in survival between groups treated with PBS, enalapril, or losartan after 12 weeks (p=0.224 for males, p=0.094 in females). In the same groups, no significant difference in maximum ascending aortic diameter was detected after treatment for 12 weeks (in males: PBS=2.69 +/− 0.19 mm, enalapril=2.04 +/− 0.27 mm, losartan=2.42 +/− 0.28 mm; p=0.24) (in females: PBS = 1.92 +/− 0.13, enalapril=1.89 +/− 0.31, losartan=1.98 +/− 0.17; p=0.86). Furthermore, aortic diameters in the FBN1 mgR/mgR mice were found to demonstrate sexual dimorphism. DISCUSSION/SIGNIFICANCE OF IMPACT: This research shows that losartan is not effective when administered after significant thoracic aortic dilation has already occurred in FBN1 mgR/mgR mice. This has important translational implications because losartan is usually not started in patients with Marfan syndrome until significant aortic dilation is already present. Therefore, more research needs to be done to determine the critical time period within which this medicine will be effective if given to patients. In addition, this research demonstrates that male FBN1mgR/mgR mice have a significantly larger aortic diameter than female FBN1mgR/mgR mice. This sexual dimorphism has recently been observed in patients with Marfan syndrome as well. Additional studies for understanding the mechanism underlying this sexual dimorphism have the potential to elucidate new therapeutic approaches for aortic disease.
3503 Restrictive feeding and excessive hunger in young children with obesity: A case series
- Sally Grace Eagleton, Callie L. Brown, Melissa J. Moses, Joseph A. Skelton
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- 26 March 2019, p. 113
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OBJECTIVES/SPECIFIC AIMS: The purpose of this case series is to show how helping parents instill a non-restrictive, structure-based (i.e., authoritative) approach to feeding is useful in addressing family food conflicts in a clinical child obesity treatment program. METHODS/STUDY POPULATION: Case reports are presented for 3 young children (two 8-year-old males and one 7-year-old female) with obesity (BMI ≥ 95th percentile for age and sex). Patients underwent family-based treatment at Brenner FIT® (Families In Training), an interdisciplinary tertiary weight management clinic. RESULTS/ANTICIPATED RESULTS: All patients experienced a period of rapid weight gain and/or severe onset obesity. Parents reported a combination of problematic eating behaviors (e.g., sneaking food, frequent complaints of hunger, vomiting from rapid consumption). Families implemented structure-based feeding with a meal-snack schedule and allowed children to eat until they were full from the food provided at meal-snack times. BMI z-score decreased from 2.19 to 2.07 in patient 1 and from 2.43 to 2.09 in patient 2 (follow-up weight was not available for patient 3). DISCUSSION/SIGNIFICANCE OF IMPACT: The improvements observed by our clinical program after families lifted restriction and instituted authoritative feeding is anecdotal evidence for the ecological validity of existing empirical work. Randomized controlled trials are needed to examine causality.
3008 Role of Interferon-gamma in Natural Clearance of Chlamydia trachomatis Infection in Women
- Stephen Jordan, Lisa Coss, Landon Wilson, Stephen Barnes, William Geisler, David Nelson
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- Published online by Cambridge University Press:
- 26 March 2019, pp. 113-114
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OBJECTIVES/SPECIFIC AIMS: Chlamydia trachomatis (CT) infection can lead to reproductive morbidity in women. Animal models suggest that protection against CT is mediated through the cytokine interferon-gamma (IFN-γ), produced by CD4+ T-cells, which clears CT through intracellular tryptophan depletion. In humans, correlates of protection remain to be elucidated, which hinders chlamydia vaccine development. Natural clearance of CT infection (e.g., clearance before antibiotics) may be an immunological correlate of protection, evidenced by (1) CT clearance without antibiotics; and (2) a 4-fold reduced risk of CT reinfection within 6 months. We have identified women with and without natural clearance of CT infection. By comparing these two groups of women, the role of IFN-γ-mediated natural clearance of CT infection will be investigated. METHODS/STUDY POPULATION: Through collaboration with a cohort study of CT-infected women, we have access to stored specimens from women who naturally cleared CT or had persisting CT infection. Using peripheral blood mononuclear cell (PBMC), we will assess whether natural clearance of CT infection is associated with IFN-γ-producing CD4+ T-cells by stimulating PBMC ex vivo with CT antigens using intracellular cytokine staining. We will also use cervicovaginal lavage (CVL) and untargeted High-Performance Liquid Chromatography-Mass Spectrometry to assess for tryptophan-dependent and -independent metabolic pathways associated with natural clearance of CT infection. RESULTS/ANTICIPATED RESULTS:: To date, IFN-γ has been measured in 10 women who did not clear CT infection, demonstrating that <20% of these women produced significant levels of IFN-γ. Women who naturally cleared CT have yet to be studied. Untargeted HPLC-MS has been performed on 6 women (3 who cleared matched to 3 with persisting CT infection). To date, 11 pathways that are significantly associated with natural clearance have been identified. DISCUSSION/SIGNIFICANCE OF IMPACT: The outcome of natural clearance of CT infection is distinct from women with persisting chlamydia. These studies may inform whether IFN-γ, produced by CD4+ T-cells, or tryptophan-dependent or -independent metabolic pathways are associated with natural clearance, which may advance chlamydia vaccine development.
3424 Serial Biomarker Monitoring Predicts Long Term Outcomes in Acute Graft Versus Host Disease
- Hrishikesh Krishna Srinagesh, Hrishikesh Krishna Srinagesh, Urvi Kapoor, Mina Aziz, Kaitlyn Ben-David, Hannah Major-Monfried, George Morales, Rachel Young, Umut Ozbek, John E Levine, James LM Ferrara
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- Published online by Cambridge University Press:
- 26 March 2019, p. 114
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OBJECTIVES/SPECIFIC AIMS: The first aim of the study is to evaluate the accuracy of serum biomarkers of acute GVHD measured after four weeks of corticosteroid therapy to predict 6 month NRM. The second aim of this study is to compare the accuracy of the biomarker algorithm to that of clinical response to corticosteroids after four weeks. The third aim of the study is to develop a novel regression model that uses weekly biomarker measurements over the first month of corticosteroid therapy to predict 6 month NRM. METHODS/STUDY POPULATION:. Patients who received HCT at one of 22 IRB-approved centers and provided blood samples to the Mount Sinai Acute GVHD International Consortium (MAGIC) biorepository and developed GVHD between January 2008 to May 2018 are included in this study. Patients were divided by time into a training set (Jan 2008-Dec 2015, n=233) for model development and a validation set (Jan 2015-May 2018, n=357) to evaluate the predictive performance of the model. The later time of the validation set was chosen deliberately to model contemporaneous GVHD treatment practices. The size of each group was designed so that there would be roughly equal numbers of deaths in both groups. RESULTS/ANTICIPATED RESULTS:. Serum concentrations of GVHD biomarkers after one month of corticosteroid therapy were measured in the validation set, and the predicted probability of NRM (
$\hat{\rm p}$) was computed according to the previously published algorithm:
$\log[-\log(1 - \hat{\rm p})]=-11.263 + 1.844({\rm logST}2)+ 0.577({\rm logREG}3\alpha)$. The performance of the biomarker algorithm was evaluated by creating receiver operating characteristic (ROC) curves and calculating the area under the curve (AUC) in the validation set. The AUC of the biomarker algorithm was a significantly better predictor of 6 month NRM than clinical response to treatment after four weeks of corticosteroids (0.84 vs. 0.64, p<0.001), which is a clinically relevant improvement in accuracy. To evaluate serial biomarker monitoring, serum biomarker concentrations will be measured weekly at five time points from treatment initiation to one month after corticosteroid therapy. We will use these values in the training set to develop a regression model for 6 month NRM that accounts for repeated biomarker measurements. The performance of this model will be tested in the validation set and the accuracy of the serial biomarker measurements will be compared to the accuracy of measuring biomarkers at the single time point after four weeks of corticosteroid therapy. An AUC improvement of 0.05 would be considered clinically significant. DISCUSSION/SIGNIFICANCE OF IMPACT: Clinical response to treatment after four weeks has been the standard endpoint in GVHD interventional trials for decades. If biomarkers measured at the same time more accurately predict long term mortality, this study would provide the basis for a novel endpoint in GVHD trials and enable more accurate determination of effect size of experimental interventions. An accurate biomarker algorithm will prove useful in guiding immunosuppressive treatment decisions for patients with GVHD. Patients identified by the algorithm as low-risk may benefit from reduced-dose corticosteroid therapy, potentially reducing lethal opportunistic infections. Patients identified as high-risk will be candidates for more intensive immunosuppression or investigational therapies. This precision medicine approach tailors therapy to the individual patient’s biology.
3158 Sunitinib-Induced Cardiotoxicity in an Engineered Cardiac Microtissue Model
- Carissa Livingston, Abhinay Ramachandran, Elise Corbin, Alexia Vite, Alexander Bennett, Kenneth Margulies
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- Published online by Cambridge University Press:
- 26 March 2019, pp. 114-115
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OBJECTIVES/SPECIFIC AIMS: The aims of this study are threefold. Firstly, we are examining the effects of increased in vitro afterload (a proxy for hypertension) on human induced pluripotent stem cell cardiomyocyte (hiPSC-CM) response to sunitinib in a durable and dynamic cardiac microtissue culture system. Secondly, we are exploring effects of repeat exposure and recovery of both sunitinib and afterload throughout the lifetime of the hiPSC-CM microtissue. Finally, we are assessing methods to prevent and treat sunitinib induced cardiotoxicity. Primary outcomes for this study are commonly utilized metrics of cardiotoxicity: degree of caspase activation, electrophysiology benchmarks for minimum voltage threshold and maximum capture rate, and microtissue force generation. METHODS/STUDY POPULATION: HiPSC-CMs are cultured and matured as 3D cardiac microtissues (CMTs) on a microtissue array. After maturation, cells are exposed to sunitinib doses of 0µM, 0.5µM, 1µM or 5µM for 12 hours. Concurrently with sunitinib dosing, increases in microtissue array stiffness are created with application of an external magnetic field. Afterload spring constants are fixed at pre-determined physiologic values ranging from 0.5µN/µm, to 5µN/µm. For Aim 1: Half of the CMTs are harvested at 8 hours after sunitinib dosing to conduct the caspase 3/7 assay, and the remainder are examined for 3 days following drug exposure to track temporal changes in electrophysiology and force generation. For Aim 2: After CMT maturation, 12-hour exposures to sunitinib are repeated three times at a fixed dose, with doses separated by one week. Concurrently with sunitinib dosing, increases or decreases in microtissue stiffness are created by changing the strength of an applied external magnetic field to create “ramp up” or “ramp down” stiffness conditions. Caspase assay and contractility metrics are measured at each timepoint. For Aim 3: Experimental conditions are conducted as described in Aim 1. Prior to the introduction of sunitinib, either carvedilol or an AMP-kinase activator is added to the CMT culture media at physiologic concentrations. Primary outcomes are examined as in Aim 1. RESULTS/ANTICIPATED RESULTS: Aim 1: We hypothesize that increases in microtissue afterload, synchronized with sunitinib exposure will augment sunitinib toxicity in cardiomyocytes resulting in elevations of caspase 3/7 activity and minimum voltage capture as well as decreases in maximum capture rate and maximum force generation. Aim 2: We hypothesize that repeat exposures to both sunitinib and to increases in afterload will augment sunitinib toxicity in CMTs via the primary outcomes mentioned in Aim 1. Additionally, we hypothesize that decreases in afterload will decrease effective sunitinib toxicity in CMTs via the primary outcomes mentioned in Aim 1. Aim 3: We hypothesize that exposure to an AMP-kinase activator but not carvedilol will decrease the effects of sunitinib toxicity in CMTs via the primary outcomes mentioned in Aim 1. DISCUSSION/SIGNIFICANCE OF IMPACT: The use of small molecule, targeted chemotherapeutic agents is increasingly common. Many of these agents cause cardiotoxic side effects, the mechanisms of which are incompletely understood. Our lab has developed a novel 3D tissue engineering platform capable of supporting durable in vitro cardiac microtissues that experience dynamic alterations in their biomechanical load. By using this platform to examine the cardiotoxic effects of sunitinib, insight into treatment and prevention of this common problem will be developed.
3127 The effect of common genetic variants in the oxytocin receptor gene on oxytocin response.
- Manasi Malik, Naiqi Shi, Geraldine Serwald, Grace Y. Lee, Antonina I. Frolova, Céline Galés, Sarah K. England
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- Published online by Cambridge University Press:
- 26 March 2019, p. 115
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OBJECTIVES/SPECIFIC AIMS: Previous studies suggest that genetic variants in the oxytocin receptor (OXTR) may alter oxytocin dose requirement for labor induction and may increase risk for preterm labor and neurodevelopmental disorders. However, the mechanisms of actions of these variants remain unknown. The goal of this study was to functionally characterize common missense and noncoding variants in OXTR. First, we aimed to determine the effects of missense variants on two major aspects of receptor function: calcium signaling and β-arrestin recruitment. Second, we used allelic expression imbalance assays in an effort to identify regulatory single nucleotide polymorphisms (SNPs) in noncoding regions of OXTR that alter OXTR mRNA expression. METHODS/STUDY POPULATION: We used the Exome Aggregation Consortium database to identify the 12 most prevalent missense single nucleotide variants in OXTR. To determine the functional effects of these variants, we transfected human embryonic kidney cells (a common model system used to study receptor function) with wild type OXTR, variant OXTR, or empty vector control. We used the calcium-sensitive dye Fluo4 to quantify intracellular calcium flux in response to oxytocin treatment, and used bioluminescence resonance energy transfer assays to measure recruitment of the signaling partner β-arrestin to the receptor. To investigate potential effects of noncoding SNPs on OXTR mRNA expression, we quantified allele-specific expression of OXTR in human uterine tissue obtained from participants at the time of Cesarean section. We used next-generation sequencing (Illumina MiSeq) to count alleles of a reporter SNP in OXTR exon 3. RESULTS/ANTICIPATED RESULTS: Of the 12 most prevalent missense single nucleotide variants, four were predicted to be deleterious by PolyPhen variant annotation software. We anticipate that these variants will alter receptor signaling through calcium or β-arrestin pathways. We further observed that a reporter SNP in OXTR exon 3 exhibits significant allelic expression imbalance in a subset of our myometrial tissue samples, indicating that OXTR expression may be regulated by a functional SNP. Our current work focuses on discovering the functional SNPs in OXTR responsible for the pattern of allelic expression imbalance seen in mRNA. In the future, we will seek to explore the effects of these variants on uterine function by using genome editing of uterine smooth muscle cells. DISCUSSION/SIGNIFICANCE OF IMPACT: Our results suggest that both missense and noncoding variants may affect OXTR expression and function. Future studies may suggest that OXTR sequencing, genotyping, or expression analysis would be useful to identify individuals likely to respond or fail to respond to safe doses of oxytocin for labor induction. Personalizing approaches for labor induction in this way would increase the safety of oxytocin and potentially reduce maternal morbidity and mortality.