B cell-associated LFA-1 and T cell-associated ICAM-1 transiently cluster in the area of contact between interacting cells.
TNP-specific B cells interact with carrier-specific T hybridoma cells in an antigen-specific, MHC-restricted manner. The formation of T cell/B cell conjugates is time and temperature dependent and results in the formation of a broad area of close contact between the interacting cells. In order to determine which surface molecules on the two cells cluster at the interaction site. T cell/B cell conjugates were formalin-fixed at different times following conjugation and were stained with antibodies directed against cell surface molecules. Results of these studies indicate that the alpha- and beta-subunits of LFA-1 on B cells transiently cluster in the area of cell contact. Maximum clustering of LFA-1 occurs at 45 min, after which time LFA-1 redistributes on the surface of the B cells. Several other B cell-associated molecules (MHC Class II, ICAM-1, Ig, B220, J11D, or CD23) do not cluster at the interaction site at any time point. T cell-associated LFA-1 does not cluster with any specific pattern, but ICAM-1 does. Maximum clustering of ICAM-1 occurs 60 to 90 min after intercellular contact. After this time, ICAM-1 redistributes on the surface of the T cells. Although both the alpha- and beta-subunits of LFA-1 cluster at the interaction site on B cells, antibodies recognizing these subunits differ in their ability to affect conjugation. One antibody recognizing the alpha chain of LFA-1 (M17/4.2) inhibits T-cell/B cell conjugation, whereas another antibody that also recognizes the alpha chain-(G-48) enhances conjugation. In contrast, an antibody that recognizes LFA-1 beta (M18/2.a.8) has no effect. An antibody that recognizes ICAM-1 (YN/1.7), the ligand for LFA-1, inhibits conjugation. These data show that, during T cell/B cell interaction. LFA-1 on B cells and ICAM-1 on T cells transiently cluster with similar, albeit not identical, kinetics to the site of cell-cell contact.
Department of Microbiology, University of Texas Southwestern Medical Center, Dallas 75235.
V M
VM
Sanders
E S
ES
Vitetta
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology* / Q000502:physiology; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000502:physiology*; D002451:Cell Compartmentation; D003572:Cytochalasins / Q000494:pharmacology; D005455:Fluorescent Antibody Technique; D007158:Immunologic Techniques; D066298:In Vitro Techniques; D018799:Intercellular Adhesion Molecule-1; D008211:Lymphocyte Cooperation; D016169:Lymphocyte Function-Associated Antigen-1 / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D013601:T-Lymphocytes / Q000166:cytology* / Q000502:physiology
D015815:Cell Adhesion Molecules; D003572:Cytochalasins; D016169:Lymphocyte Function-Associated Antigen-1; D018799:Intercellular Adhesion Molecule-1