Gm-3.2, a new granulocyte/macrophage alloantigen.

A monoclonal antibody defining a unique mouse neutrophil cell-surface antigen, Gm-3.2, is described. Gm-3.2 is found on all neutrophils in peritoneal exudates and in bone marrow, and is also present on macrophages activated by thioglycolate but is absent from lymphoid, kidney, liver, heart, and red cells. Gm-3.2 is a differentiation antigen of myeloid cells, as granulocyte/macrophage colony-forming cells are Gm-3.2- while mature neutrophils are Gm-3.2+. Strain distribution pattern analysis shows linkage of the Gm-3 locus to the Ly-4, B2m, H-3 complex on chromosome 2.