Leu-M1 antigen expression in acute XXXX .

@entity1 @entity981 @entity706 @entity784 @entity3052 @entity1778 @entity1892 @entity1893
Leu-M1 is a differentiation antigen present in @entity1 myelomonocytic cells. Seventy-seven acute @entity1778 were retrospectively stained with anti-Leu-M1 using the immunoperoxidase technique on Bouin-fixed paraffin-embedded sections. The subjects were 44 @entity981 ( @entity981 ) and 33 @entity3052 ( @entity3052 ) previously characterized by cytochemical and immunologic (cell suspension) methods. Leu-M1 was positive in all the @entity3052 and in half of the @entity981 cases. These results suggest that Leu-M1 does not allow differentiation between @entity3052 and @entity981 . For the @entity981 cases Leu-M1 was positive in 15/28 B-cell types, 4/12 T-cell type and 3/4 'null'-cell type cases. Thus, this antibody is of no assistance in defining types B, T, or 'null' in @entity981 . Leu-M1 was also studied on paraffin sections of 34 high grade @entity706 . The antibody was negative in all 13 @entity1892 (lymphoblastic: 6; immunoblastic: 7) and in all 4 'null' cell lymphomas. It was positive in 4/9 peripheral T-cell type, the other @entity784 (lymphoblastic: 5; immunoblastic: 3) remaining negative. Thus, Leu-M1 may be positive in @entity784 but it is negative in @entity1892 and is always negative in B or T lymphoblastic types. It seems that lymphoblasts are Leu-M1 negative in @entity1893 and may be @entity1778 .
