title: Monoclonal antibody specific for T cell-derived human IgE binding factors.
abstract: A B cell hybridoma secreting monoclonal antibody against human IgE binding factors was obtained by immunization of BALB/c mice with partially purified IgE binding factors, and fusion of their spleen cells with SP-2/0-AG14 cells. The monoclonal antibody bound all of the 60,000, 30,000, and 15,000 dalton IgE binding factors from two T cell hybridomas and those from activated T cells of a normal individual. The antibody bound both IgE-potentiating factors, which had affinity for lentil lectin, and IgE-suppressive factors, which had affinity for peanut agglutinin. However, the monoclonal anti-IgE-binding factor bound neither Fc epsilon R on RPMI 8866 cells nor IgE binding factors from the B lymphoblastoid cells. A monoclonal antibody against Fc epsilon R on B cells (H107) bound the 60,000 and 30,000 dalton IgE binding factors from both T cell hybridomas and RPMI 8866 cells but did not bind the 15,000 dalton IgE binding factors from either T cells or B cells. The results indicate that T cell-derived IgE binding factors have a unique antigenic determinant that is lacking in both Fc epsilon R on B cells and B cell-derived IgE binding factors. The anti-IgE binding factor and anti-Fc epsilon R monoclonal antibodies both failed to stain cell surface components of IgE binding factor-producing T cell hybridomas. However, both antibodies induced the T cell hybridoma to form IgE binding factors. The results suggest that the T cell hybridomas bear low numbers of Fc epsilon R that share antigenic determinants with IgE binding factors secreted from the cells.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D001402:B-Lymphocytes / Q000032:analysis; D000939:Epitopes / Q000276:immunology; D006801:Humans; D006825:Hybridomas / Q000276:immunology; D037102:Lectins / Q000378:metabolism; D008222:Lymphokines / Q000276:immunology* / Q000302:isolation & purification; D051379:Mice; D008807:Mice, Inbred BALB C; D029584:Prostatic Secretory Proteins; D011961:Receptors, Fc / Q000276:immunology*; D017455:Receptors, IgE; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000032:analysis
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D037102:Lectins; D008222:Lymphokines; D029584:Prostatic Secretory Proteins; D011961:Receptors, Fc; D017455:Receptors, IgE; C043076:beta-microseminoprotein; C013059:immunoglobulin-binding factors