title: Lymphocyte function-associated antigen-1 expression on plasma cells correlates with tumor growth in multiple myeloma.
abstract: Lymphocyte function-associated antigen-1 (LFA-1) (CD11a/CD18) expression on bone marrow-derived plasma cells from normal individuals, patients with monoclonal gammopathies of undetermined significance (MGUS), and patients with multiple myeloma (MM) was studied by immunofluorescence microscopy and flow cytometry using a new monoclonal antibody (MoAb) F8.8. This MoAb recognizes the alpha-chain (CD11a) of LFA-1 as determined by immunoprecipitation, and inhibits T-cell-induced cytotoxicity. Although the F8.8 MoAb stains unstimulated peripheral blood T cells with the same mean fluorescence intensity as other anti-CD11a MoAbs, it proved to be superior in detecting CD11a on plasma cells as compared with reference MoAbs. Using the anti-CD11a MoAb F8.8, a strong correlation was found between LFA-1 expression and disease activity in MM, as defined by clinical performance and serum M-protein level. Hardly any LFA-1+ plasma cells were detected in normal individuals, patients with MGUS, and MM patients in a nonactive phase of their disease, while plasma cells of some MM patients with active disease and all patients with fulminant disease expressed LFA-1. Plasma cell LFA-1 expression correlated well with the labeling index (LI) of the tumors in the individual patients. The relation between LFA-1 expression and the tumor growth suggests an involvement of this adhesion molecule in cellular interactions resulting in plasma cell proliferation.
authors.affiliation: Department of Haematology, University Hospital, Utrecht, The Netherlands.
authors.forename: E J
authors.initials: EJ
authors.lastname: Ahsmann
authors.forename: H M
authors.initials: HM
authors.lastname: Lokhorst
authors.forename: A W
authors.initials: AW
authors.lastname: Dekker
authors.forename: A C
authors.initials: AC
authors.lastname: Bloem
mesh_terms: D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000032:analysis; D014408:Biomarkers, Tumor / Q000032:analysis*; D001853:Bone Marrow / Q000276:immunology / Q000473:pathology*; D003602:Cytotoxicity, Immunologic; D005260:Female; D005455:Fluorescent Antibody Technique; D005500:Follow-Up Studies; D006412:Hematopoietic Stem Cells / Q000276:immunology / Q000473:pathology*; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D016169:Lymphocyte Function-Associated Antigen-1 / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D008940:Mitotic Index; D008970:Molecular Weight; D009101:Multiple Myeloma / Q000276:immunology / Q000473:pathology*; D010641:Phenotype; D012016:Reference Values; D013601:T-Lymphocytes / Q000276:immunology* / Q000473:pathology
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D014408:Biomarkers, Tumor; D007136:Immunoglobulins; D016169:Lymphocyte Function-Associated Antigen-1