Modeling T cell mediated suppression. Deriving implications for cancer immunotherapy.

Not Supplied.

Cell polarity and tissue morphogenesis: geometry and dynamics.

Not Supplied.

Modelling of naive CD4+ T cell dynamics during human life in healthy and HIV infected individuals.

The density-dependent mechanisms responsible for homeostasis of naive CD4+ T cells remain an open question in immunology. In the presence of a decreasing thymic output, homeostatic mechanisms are responsible for a relatively constant naive CD4+ population throughout life. T cell rearrangement excision circles (TRECs), that are present in a constant fraction of the cells produced by the thymus, but are diluted with each cell division, help to shed some light on proliferation and life spans of the naive cells. The hypothesis which forms the backbone of our model is based on the distinct status that can be ascribed to the population of recent thymic emigrants (RTEs). In the model we take the extreme view that RTEs form a specific compartment in T cell development, which is responsible for all proliferation in the total naive pool. Furthermore, by means of a density-dependent entry of these RTEs in the truly naive compartment, they are able to regulate naive CD4+ T cell homeostasis. In our study we showed that many experimental data can be explained by a model based on these two assumptions. In addition, the model provides insight in the mechanisms in which HIV might deplete naive CD4+ T cell numbers and the consequences of these mechanisms on the naive cell TREC content.