Its activity is essential for the generation of B cell but not of T cell precursors , although the differentiation of the latter is not normal .
its activity is essential for the generation of b cell but not of t cell precursors , although the differentiation of the latter is not normal .
O O O O O O O O B-cell_type I-cell_type O O O B-cell_type I-cell_type I-cell_type O O O O O O O O O O O