A novel human leucocyte surface membrane antigen defined by murine monoclonal antibody.
A murine monoclonal antibody has been produced which identifies a novel human leucocyte differentiation antigen. The antibody, designated WM-66, of IgM subclass, was cytolytic with human complement. WM-66 was shown to react with virtually all normal T and B lymphocytes from peripheral blood and lymphoid tissues, as well as blood monocytes and approximately 40% of bone marrow mononuclear cells. The antibody also bound to the majority of cases of chronic B-cell malignancies, including chronic lymphatic leukaemia and non-Hodgkin's lymphoma, but not to cases of acute leukaemia or to the majority of leukaemic and lymphoblastoid cell lines. WM-66 also reacted with epithelium of bronchus and salivary gland ducts. A single band of relative molecular mass 65,000 Daltons was immunoprecipitated from membrane extracts of normal lymphocytes and the B-cell line Daudi. Treatment of a number of WM-66-negative B-cell lines with neuraminidase resulted in WM-66 binding, indicating that the antigen exists in a covert form masked by sialic acid residues on a wider spectrum of cell types than was initially apparent. The reactivity pattern of WM-66 indicates that it recognises a previously undescribed surface membrane molecule with broad non-lineage-specific distribution on leucocytes. This has recently been confirmed at the Fourth International Workshop on Human Leucocyte Differentiation Antigens. Although the biological function of the molecule recognised by WM-66 is unknown, the lytic properties of the antibody suggest a possible in vivo therapeutic role as an immunosuppressant or for treatment of lymphoid malignancy.
Henniker
A J
AJ
Department of Haematology, Westmead, NSW, Australia.
Bradstock
K F
KF
Grimsley
P
P
Atkinson
K
K
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology* / Q000494:pharmacology; D000954:Antigens, Surface / Q000032:analysis / Q000737:chemistry / Q000276:immunology*; D002455:Cell Division / Q000187:drug effects; D002462:Cell Membrane / Q000737:chemistry / Q000276:immunology / Q000648:ultrastructure; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007962:Leukocytes / Q000737:chemistry / Q000276:immunology* / Q000648:ultrastructure; D008221:Lymphoid Tissue / Q000166:cytology / Q000276:immunology / Q000648:ultrastructure; D008264:Macrophages / Q000166:cytology / Q000276:immunology / Q000648:ultrastructure; D051379:Mice; D008807:Mice, Inbred BALB C; D011233:Precipitin Tests
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface