title: The increase of CD5LOW+NK cells in patients with multiple myeloma and plasmacytoma.
abstract: CD5 antigen is present on all normal alpha beta T cells and some B cells. Human NK cells do not usually express CD5 antigen, but we found a novel subset of CD5LOW (low density of CD5) positive (CD5LOW+) natural killer cells (NK cells) in patients with multiple myeloma (MM) and plasmacytoma. To detect CD5LOW+NK cells, we examined the lymphocytes of 23 patients with MM and plasmacytoma by flow cytometry. Five out of 23 patients had CD5LOW+NK populations. These patients had many more NK cells than the other patients in the peripheral blood and bone marrow. The CD5LOW+NK cells had CD2, low density of CD8, CD16 and CD56, but no CD3, CD19, or CD20. Most of the CD5LOW+NK cells had HLA-DR, unlike the CD5-NK cells. Sorted CD5LOW+CD16+ populations were large granular lymphocytes (LGL). The CD5LOW+NK cells had some lytic activity on K562 cells in a 4-hour 51Cr release assay. Our results indicate that there is a novel subset of NK cells in some patients with MM and plasmacytoma and that CD5LOW+NK cells may be associated with NK cell activation.
authors.affiliation: Department of Hematology, Showa University School of Medicine, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ishiyama
authors.forename: K
authors.initials: K
authors.lastname: Watanabe
authors.forename: K
authors.initials: K
authors.lastname: Fukuchi
authors.forename: K
authors.initials: K
authors.lastname: Yajima
authors.forename: M
authors.initials: M
authors.lastname: Koike
authors.forename: S
authors.initials: S
authors.lastname: Tomoyasu
authors.forename: N
authors.initials: N
authors.lastname: Tsuruoka
mesh_terms: D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000032:analysis* / Q000097:blood; D001853:Bone Marrow / Q000276:immunology / Q000473:pathology; D018956:CD5 Antigens; D005260:Female; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood / Q000276:immunology* / Q000473:pathology; D010954:Plasmacytoma / Q000097:blood / Q000276:immunology* / Q000473:pathology; D012016:Reference Values
chemical_list: D015703:Antigens, CD; D018956:CD5 Antigens