title: Suppression of IgE synthesis in mouse plasma cells and B cells by rat IgE-suppressive factor.
abstract: Rat IgE-binding factors were assessed for the ability to regulate the IgE response of mouse spleen cells. A rat-mouse T cell hybridoma, 23B6, produced two species, i.e., 15,000 (15K) daltons and 30K daltons, of rat IgE-binding factors upon incubation with rat IgE. The 15K IgE-binding factor selectively suppressed the in vitro IgE response of DNP-KLH-primed BALB/c spleen cells to homologous antigen without affecting the IgG1 response, whereas the 30K IgE-binding factor failed to affect both the IgE and IgG1 responses. Incubation of IgE-producing hybridoma cells with the 15K IgE-binding factor resulted in a parallel decrease in the proportion of IgE-secreting cells, cytoplasmic IgE-containing cells, and sIgE+ cells. The same IgE-binding factor suppressed IgE formation by mouse plasma cells in DNP-KLH-primed or KLH-primed BDF1 mice without affecting the IgG1-forming cells. In contrast, the 30K IgE-binding factor failed to affect the formation of IgE by the hybridoma and the plasma cells. It was also found that incubation of the splenic lymphocytes with the 15K IgE-binding factor resulted in a decrease in sIgE+ B cells; the 30K IgE-binding factor failed to do so. The results indicate that the binding of the 15K IgE-binding factor to plasma cells and to sIgE+ B cells results in suppression of IgE synthesis in these cells.
mesh_terms: D000818:Animals; D000921:Antibody-Producing Cells / Q000378:metabolism*; D001402:B-Lymphocytes / Q000378:metabolism*; D006825:Hybridomas / Q000378:metabolism; D007108:Immune Tolerance; D007073:Immunoglobulin E / Q000096:biosynthesis* / Q000502:physiology*; D008222:Lymphokines / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010950:Plasma Cells / Q000378:metabolism; D029584:Prostatic Secretory Proteins; D051381:Rats; D011917:Rats, Inbred Lew; D013154:Spleen / Q000166:cytology; D013491:Suppressor Factors, Immunologic
chemical_list: C037161:IGE class-specific suppressor factor; D008222:Lymphokines; D029584:Prostatic Secretory Proteins; D013491:Suppressor Factors, Immunologic; C043076:beta-microseminoprotein; C013059:immunoglobulin-binding factors; D007073:Immunoglobulin E