Ontogeny of thymocytes in sea bass Dicentrarchus labrax: studies with monoclonal antibodies.

The monoclonal antibody DLT15 directed against thymocytes of the sea bass Dicentrarchus labrax specifically recognised an antigen determinant(s) expressed during development of thymic lymphoid cells. While immunoreaction is excluded from lymphoblast-like cells present in the thymic anlage, it was first detected one month posthaching in thymocytes. Thereafter, a marked increase in number of immunoreactive cells occurred mostly in the outer region of the thymus. This study aimed to analyse the chronology and some features of thymocyte differentiation