CD45 regulates thymocyte survival during development in fetal thymic organ culture.

The CD45 protein tyrosine phosphatase is essential for T cell development. Its external domain undergoes changes in glycosylation and isoform usage during thymocyte development, the consequences of which remain unknown. The contribution of this complex external domain to T cell development is unknown so we sought to examine the impact of CD45 engagement on T cell development.