title: In vivo isotype regulation of humoral responses to dextran B1355 in BALB/c mice. Double-class IgG3/IgM producers as a function of age.
abstract: This report shows that, in 8- to 10-month-old BALB/c mice immunized intraperitoneally with dextran B1355, approximately 75% of IgG3 anti-alpha (1----3) polyglucan (anti-dex) plaque-forming cells (PFC) detected in the spleen were identified as double-Ig class producers secreting simultaneously IgG3 and IgM antibodies with the same specificity for the dex epitope. Under the same conditions of immunization, however, IgA anti-dex PFC were mostly single-class secretors. IgA PFC developed in the spleen in highest numbers (equal to IgM), but in Peyer's patches IgA PFC were sevenfold more numerous than IgM. Furthermore, spleen IgG3 anti-dex PFC responses were low compared with spleen IgA and IgM anti-dex PFC responses and appeared only late in ontogeny. The possibility is discussed whether a TH dependence of the IgA anti-dex response and a TH-independent generation of the IgG3 response are responsible for the different pattern of isotype expression.
authors.forename: D A
authors.initials: DA
authors.lastname: Rivier
authors.forename: P E
authors.initials: PE
authors.lastname: Trefts
authors.forename: K A
authors.initials: KA
authors.lastname: Cook
mesh_terms: D000375:Aging; D000818:Animals; D000921:Antibody-Producing Cells / Q000145:classification / Q000378:metabolism / Q000502:physiology; D001854:Bone Marrow Cells; D003911:Dextrans / Q000008:administration & dosage / Q000276:immunology*; D005260:Female; D006462:Hemolytic Plaque Technique; D007070:Immunoglobulin A / Q000096:biosynthesis; D007126:Immunoglobulin Allotypes / Q000096:biosynthesis / Q000502:physiology*; D007074:Immunoglobulin G / Q000096:biosynthesis* / Q000502:physiology; D007075:Immunoglobulin M / Q000096:biosynthesis* / Q000502:physiology; D008198:Lymph Nodes / Q000166:cytology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000166:cytology
chemical_list: D003911:Dextrans; D007070:Immunoglobulin A; D007126:Immunoglobulin Allotypes; D007074:Immunoglobulin G; D007075:Immunoglobulin M