title: Structural and functional characteristics of hairy cells.
abstract: Morphological, cytochemical, immunological and ultrastructural studies were performed on peripheral blood mononuclear cells from a patient with hairy-cell leukemia. Immunofluorescence studies showed a very strong intensity of fluorescence and indicated that hairy cells had monoclonal surface-membrane immunoglobulins (SmIg) actively produced by the cells. An unusual spontaneous SmIg redistribution induced by antibodies was also noted. Immunoultrastructural studies demonstrated that antibody-induced redistribution of SmIg on hairy cells is in form of a singular polar cap and that the cell membrane is rapidly cleaned of the complexes by endocytosis. The behavior of hairy cells regarding several membrane markers, mitogen stimulation and antibody-induced cytotoxicity suggests that hairy projections could represent the expression of a functional stage common to different lymphocyte subpopulations, or alternatively, a marker of a peculiar subset of B lymphocytes.
mesh_terms: D000912:Antibodies, Neoplasm; D000954:Antigens, Surface; D001402:B-Lymphocytes / Q000276:immunology; D001773:Blood Cells / Q000502:physiology / Q000648:ultrastructure*; D002462:Cell Membrane / Q000648:ultrastructure; D003601:Cytotoxicity Tests, Immunologic; D005455:Fluorescent Antibody Technique; D006801:Humans; D007124:Immunoenzyme Techniques; D007152:Immunologic Capping; D007943:Leukemia, Hairy Cell / Q000097:blood* / Q000276:immunology / Q000648:ultrastructure; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D008934:Mitogens / Q000494:pharmacology; D009000:Monocytes / Q000502:physiology / Q000648:ultrastructure; D011947:Receptors, Antigen, B-Cell / Q000032:analysis
chemical_list: D000912:Antibodies, Neoplasm; D000954:Antigens, Surface; D008934:Mitogens; D011947:Receptors, Antigen, B-Cell