Calcium signals in helper T cells after interaction with antigen-specific and antigen-nonspecific B cells.
By confocal fluorescence microscopy we have studied the rises of the intracellular free calcium ion concentration ([Ca2+]i) in helper T cells (KLH-specific, I-Ak-restricted Th1 cells, 28-4) after interaction with antigen-specific and antigen-nonspecific B cells (antigen-presenting cells). Antigen-specific and antigen-nonspecific B cells were prepared by the preincubation of TNP (trinitrophenol)-specific B cell hybridomas (TP67.21 I-Ak) with TNP-conjugated KLH and KLH alone, respectively. Calcium signals in Th1 cells (28-4) were induced by antigen-specific B cells one hundred times more efficiently as those by antigen-nonspecific B cells. Herbimycin A, a tyrosine kinase inhibitor, suppressed the former signals but not the latter. These results indicated that tyrosine phosphorylation was involved in the antigen processing of antigen-specific B cells but not in the processing of antigen-nonspecific B cells.
Nagao
Y
Y
Faculty of Pharmaceutical Sciences, Nagoya City University, Japan.
Noji
M
M
Asano
Y
Y
Hamano
T
T
Nakanishi
M
M
D000818:Animals; D000941:Antigens / Q000276:immunology; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D016227:Benzoquinones; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D006433:Hemocyanins / Q000276:immunology; D047029:Lactams, Macrocyclic; D008213:Lymphocyte Activation; D051379:Mice; D018613:Microscopy, Confocal; D010851:Picrates / Q000276:immunology; D011809:Quinones / Q000494:pharmacology; D011947:Receptors, Antigen, B-Cell / Q000276:immunology; D011956:Receptors, Cell Surface / Q000276:immunology / Q000378:metabolism; D017828:Rifabutin / Q000031:analogs & derivatives; D015398:Signal Transduction; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology* / Q000378:metabolism
D000941:Antigens; D016227:Benzoquinones; D047029:Lactams, Macrocyclic; D010851:Picrates; D011809:Quinones; D011947:Receptors, Antigen, B-Cell; D011956:Receptors, Cell Surface; D017828:Rifabutin; C020754:herbimycin; D006433:Hemocyanins; C005858:picric acid; C032808:keyhole-limpet hemocyanin; D002118:Calcium