Characterization of CD44 antigen during lymphoid ontogeny.

ABSTRACT

We studied immunohistological and biochemical aspects of the CD44 molecule with a mAb produced in our lab GRHL-1. The characteristic expression of this antigen in cells of B lineage was analyzed. This mAb showed identical immunohistological patterns of reactivity to other mAbs included in CD44 cluster, on a variety lymphoid and nonlymphoid human tissues, and demonstrated similar bands on SDS-PAGE of 125I labeled lymphocyte lysates. This antigen is limited to cells of mature phenotype, and disappears in proliferating B cells in the germinal centers of the lymphoid follicles. CD44 is absent in pre-B and Burkitt cell lines. PKC activation mediate in vitro differentiation of pre-B cell lines. However, it is not involved in up-regulation of CD44 antigen expression.