title: The role of lymphocyte function-associated antigen 1 (LFA-1) in the adherence of T lymphocytes to B lymphocytes.
abstract: The functional role of the LFA-1 molecule in the interaction between helper T lymphocytes and B lymphocytes was investigated using lymphocytes from patients with leukocyte adhesion deficiency, an inherited immunodeficiency characterized by a defective leukocyte expression of the LFA-1, Mac-1 (CR3) and p150,95 molecules. The ability of LFA-1- T lymphocytes to provide antigen-specific help for HLA-identical LFA-1+ B lymphocytes was reduced while their antigen-specific activation was normal. Antigen-independent conjugate formation between resting, nonactivated LFA-1- T lymphocytes and LFA-1+ B lymphocytes was impaired while LFA-1- B lymphocytes bound LFA-1+ T lymphocytes normally. Conjugate formation of activated LFA-1- T lymphocytes was mostly mediated by the CD2-LFA-3 adhesion pathway while the ICAM-1 molecule, a ligand of LFA-1, had no function. These results demonstrate that LFA-1 plays a major role in the cognate interaction between helper T lymphocytes and B lymphocytes that cannot be mediated instead by CD2 or other molecules on resting T lymphocytes.
mesh_terms: D000914:Antibodies, Viral / Q000096:biosynthesis; D000917:Antibody Formation; D000943:Antigens, Differentiation / Q000276:immunology*; D000954:Antigens, Surface / Q000502:physiology*; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules; D006801:Humans; D009980:Influenza A virus / Q000276:immunology; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D016169:Lymphocyte Function-Associated Antigen-1; D009000:Monocytes / Q000166:cytology / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D000943:Antigens, Differentiation; D000954:Antigens, Surface; D015815:Cell Adhesion Molecules; D016169:Lymphocyte Function-Associated Antigen-1