title: B-cell depletion fails to abrogate the induction of oral tolerance of specific Th1 immune responses in mice.
abstract: Antigen presentation by resting B cells has been shown to induce peripheral tolerance to intravenous (i.v.) administered soluble protein antigens. We further examined the role of resting B cells in the induction of oral tolerance. Mice were treated continuously from birth with rabbit antimouse IgM serum for 5 weeks. Immunohistological studies revealed that anti-IgM treatment depleted B cell-aggregated follicles in intestinal Peyer's patches. At 4-weeks-old, B cell-depleted mice were fed 25 mg ovalbumin or given 10% chicken egg white to drink for 5 days. Anti-IgM treatment was stopped 2 days after the last feed. Ten weeks later, the mice were immunized with 100 microg ovalbumin emulsified with complete Frund's adjuvant. Their T helper 1 (Th1) cell-regulated systemic delayed-type hypersensitivity, IgG2a antibody responses and spleen cell production of interferon-r and interleukin-2 were suppressed by prior ovalbumin or egg white feeding during anti-IgM treatment. Active suppression of Th1 immune responses was also demonstrated following adoptive transfer of egg white-fed donor spleen cells collected during anti-IgM treatment to naïve recipients. Although enormous small resting B cells are aggregated in the mantle zones of follicles of intestinal Peyer's patches, they are not the antigen-presenting cells seen in the induction of oral tolerance.
authors.affiliation: Department of Medical Research, Veterans General Hospital-Taipei, Taipei, Taiwan.
authors.forename: H J
authors.initials: HJ
authors.lastname: Peng
authors.forename: Z N
authors.initials: ZN
authors.lastname: Chang
authors.forename: C C
authors.initials: CC
authors.lastname: Lee
authors.forename: S W
authors.initials: SW
authors.lastname: Kuo
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D005260:Female; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007108:Immune Tolerance / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology; D007376:Interleukin-2 / Q000276:immunology; D017493:Leukocyte Common Antigens / Q000276:immunology; D008212:Lymphocyte Depletion; D008297:Male; D051379:Mice; D010047:Ovalbumin / Q000276:immunology; D011817:Rabbits; D013154:Spleen / Q000166:cytology / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology*
chemical_list: D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007376:Interleukin-2; D007371:Interferon-gamma; D010047:Ovalbumin; D017493:Leukocyte Common Antigens