title: Association of specific tyrosine phosphorylation with stages of B-cell differentiation in human lymphoid leukemias.
abstract: In vitro protein phosphorylation in various types of human fresh lymphoid leukemic cells (C-ALL, B-CLL, HCL and PCL: B-cell lineage and T-ALL, ATL and T-CLL: T-cell lineage) were studied. In cases of B-CLL and HCL, tyrosine protein kinase (TPK) activity was at least 5-fold higher than that in other cases of B- and T-cell lineages. B-cell leukemic cells at various differentiation stages had different endogenous substrates in tyrosine phosphorylation as well as distinct TPK activity. The P-tyr-containing proteins of 68K, 59K and 56K were detected commonly in all the cases of B-cell lineage. The phosphorylated protein of 32K was present only in cases of PCL. On the other hand, in T-ALL and ATL, the major substrate in tyrosine phosphorylation was 58K. These results suggest that the characterization of in vitro tyrosine phosphorylation provides a new means not only to distinguish T- and B-lymphoid leukemia, but also to differentiate stages of lymphoid development.
mesh_terms: D001402:B-Lymphocytes / Q000378:metabolism*; D001798:Blood Proteins / Q000378:metabolism; D002454:Cell Differentiation; D006801:Humans; D007938:Leukemia / Q000097:blood* / Q000145:classification; D007945:Leukemia, Lymphoid / Q000097:blood*; D009363:Neoplasm Proteins / Q000097:blood; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000097:blood; D013601:T-Lymphocytes; D014443:Tyrosine / Q000097:blood*
chemical_list: D001798:Blood Proteins; D009363:Neoplasm Proteins; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases