Cross-linking of CD38 molecules induced expression of interleukin-2 receptor (IL-2R) and HLA-DR on human thymocytes

CD38 is a 45 KD glycoprotein which is mainly expressed on early lymphoid progenitors and plasma cells. Role and function of CD38 on thymocytes and plasma cells has not yet been elucidated. By cross-linking of CD38 molecules using a specific monoclonal antibody on thymocytes and a neoplastic T cell line (Jurkat), it was shown that percentage of HLA-DR and IL-2R molecules is significantly upregulated. Moreover, CD11a and CD18 were among two adhesion molecules which showed a sharp increase in expression, whereas no changes on expression of CD11b, CD44 and CD54 were detected. Spontaneous proliferation of Jurkat cell line after addition of different concentrations of CD38 monoclonal antibody was unchanged.