This paper extends the volume filling chemotaxis model [18, 26] by taking into account the cell population interactions. The
extended chemotaxis models have nonlinear diffusion and chemotactic sensitivity depending
on cell population density, which is a modification of the classical Keller-Segel model in
which the diffusion and chemotactic sensitivity are constants (linear). The existence and
boundedness of global solutions of these models are discussed and the numerical pattern
formations are shown. The further improvement is proposed in the end.