Characterization of two monoclonal antibodies (UCL4D12 and UCL3D3) that discriminate between human mantle zone and marginal zone B cells.
Two new monoclonal antibodies (MoAbs), UCL3D3 and UCL4D12 were obtained following immunization with follicular lymphoma (UCL3D3) or low-grade primary B cell gastric lymphoma cells (UCL4D12). In normal splenic white pulp, tonsil and small intestinal Peyer's patches, UCL4D12 recognizes marginal zone B cells and a subpopulation of follicle centre cells, whereas mantle zone B cells are UCL4D12 negative. In contrast, UCL3D3 recognizes mantle zone B cells and follicular dendritic cells, but not marginal zone B cells or follicle centre B cells. Double-immunofluorescence studies showed that in the splenic white pulp, these antibodies stain reciprocally. The majority of UCL3D3+ cells are sIgM+ and sIgD+ whereas a higher proportion of UCL4D12+ cells express surface IgM (sIgM) but not surface IgD (sIgD). Less than 10% of splenic B cells express both 3D3 and 4D12 antigens. None of the cell lines tested expressed either antigen. Functional studies showed that both antigens play a role in B cell activation as the MoAbs increase the mitogenic effect of Staphylococcus aureus Cowan I on tonsil B cells. This effect was maximal at 72 h in culture. TPA activation was reduced, and no effect was observed with anti-immunoglobulin (anti mu) or CDw40 (G28.5). UCL3D3 and UCL4D12 did not show any stimulatory effect on their own. Biochemical studies show that both MoAbs recognize proteins of 80-90 kD under reducing conditions. These two MoAbs appear to recognize new B cell surface antigens which may be useful for identifying subpopulations of B cells.
Imperial Cancer Research Fund-Human Tumour Immunology Group, Courtauld Institute, London, England, U.K.
J
J
Smith-Ravin
J
J
Spencer
P C
PC
Beverley
P G
PG
Isaacson
D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000276:immunology*; D000954:Antigens, Surface / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007124:Immunoenzyme Techniques; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D016131:Lymphocyte Subsets / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D014066:Palatine Tonsil / Q000166:cytology / Q000276:immunology; D013154:Spleen / Q000166:cytology / Q000276:immunology
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface