In fetal liver of PU . 1-/- mice , which lack lymphoid and myeloid cells , expression of Btk was reduced two- to threefold but not abolished .
in fetal liver of pu . 1-/- mice , which lack lymphoid and myeloid cells , expression of btk was reduced two- to threefold but not abolished .
O B-body_part I-body_part O B-multi_cell I-multi_cell I-multi_cell I-multi_cell O O O O O O O O O O B-protein_molecule O O O O O O O O O