Journal Article

Suppressive Effects of 2,3,7,8-Tetrachlorodibenzo-<i>p</i>-dioxin (TCDD) on the High-Affinity Antibody Response in C57BL/6 Mice

Kaoru Inouye, Tomohiro Ito, Hidekazu Fujimaki, Yoshimasa Takahashi, Toshitada Takemori, Xiaoqing Pan, Chiharu Tohyama and Keiko Nohara

in Toxicological Sciences

Volume 74, issue 2, pages 315-324
Published in print August 2003 | ISSN: 1096-6080
Published online August 2003 | e-ISSN: 1096-0929 | DOI: http://dx.doi.org/10.1093/toxsci/kfg132
Suppressive Effects of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) on the High-Affinity Antibody Response in C57BL/6 Mice

More Like This

Show all results sharing these subjects:

  • Medical Toxicology
  • Toxicology (Non-medical)

GO

Show Summary Details

Preview

In the humoral immune response to an invasion of foreign antigens, B cells differentiate into low-affinity antibody-forming cells (AFCs) that mainly secrete IgM or, through germinal center (GC) formation, into high-affinity AFCs that secrete IgG-class antibodies with a higher affinity for the antigen. Previous studies have established the suppressive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on low-affinity antibody responses to antigens. However, whether and how TCDD affects the high-affinity antibody response to antigens has not yet been clarified. In this paper we investigate the effects of TCDD on GC formation, high-affinity AFC generation, and high-affinity antibody production in the primary humoral immune response. C57BL/6 mice were orally administered 0 or 20 μg/kg of TCDD and subsequently immunized with alum-precipitated ovalbumin (OVA) on day 0. Then the GC formation in the spleen and OVA-specific antibodies in the plasma, was evaluated until day 14 postimmunization. TCDD exposure reduced the production of OVA-specific IgG1 on days 10 and 14. GC formation in the spleen was also suppressed by TCDD exposure, and the suppression persisted from day 7 until day 14. In TCDD-administered mice, on day 7, cellular proliferation in the GCs was significantly suppressed, although apoptosis was not markedly affected. In order to measure high-affinity antibody and high-affinity AFCs, the mice were administered TCDD followed by immunization with alum-precipitated (4-hydroxy-3-nitrophenyl) acetyl linked to chicken γ-globulin (NP-CG). The frequency of high-affinity NP-specific AFCs that bind to low-haptenated antigen was clearly shown to be reduced in the spleen on days 10 and 14. Furthermore, the high-affinity anti-NP IgG1 levels on days 10 and 14 postimmunization were significantly reduced by TCDD exposure. Taken together, the results of this paper demonstrate that TCDD exposure inhibits the generation of high-affinity AFCs and high-affinity antibody production during the primary humoral immune response and suggest that these alterations were caused by the suppression of antigen-responding B-cell proliferation induced by TCDD during GC formation.

Keywords: TCDD; germinal center; high-affinity antibody-forming cell; high-affinity antibody; immune suppression; humoral immunity

Journal Article.  6419 words.  Illustrated.

Subjects: Medical Toxicology ; Toxicology (Non-medical)

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.