title: Enzyme-induced modification of the surface properties of lymphoid cells in malignant disease. I. Effect of trypsin on rosette formation by lymphocytes in myelomatosis.
abstract: The surface properties of blood lymphocytes from treated myeloma patients and healthy controls were studied in vitro. The patients were tested 6 weeks after the last treatment to allow time for cells to recovery from possible drug toxicity. Peripheral-blood lymphocytes were tested for rosette formation with unsensitized sheep erythrocytes (E rosettes) and with complement and antibody-coated erythrocytes (EAC rosettes). The tests were duplicated using lymphocytes pretreated with trypsin. As others have noted, myelomatosis is associated with increased blood levels of EAC-rosette-forming cells and a marked reduction in E-rosette-forming cells. E-rosette formation was significantly increased by pretreatment of myeloma lymphocytes with trypsin. By contrast, enzyme-treated cells showed no significant change in EAC-rosette formation. These results suggest that the absolute number of circulating T cells is probably not reduced in myelomatosis, but that the surface of T cells is somehow modified so that a proportion of them lose the ability to form E rosettes.
mesh_terms: D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology; D004305:Dose-Response Relationship, Drug; D006801:Humans; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology*; D009101:Multiple Myeloma / Q000276:immunology*; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology; D014357:Trypsin / Q000494:pharmacology*
chemical_list: D014357:Trypsin