KINETICS OF SPECIFIC IMMUNOGLOBULIN-A, IMMUNOGLOBULIN-M AND IMMUNOGLOBULIN-G PRODUCTION IN THE DUODENAL AND CECAL MUCOSA OF CHICKENS INFECTED WITH EIMERIA-ACERVULINA OR EIMERIA-TENELLA

The development and appearance of antibody was studied in the intestin e and serum from histocompatible GB1 chickens orally infected with ooc ysts of Eimeria acervulina (restricted to the duodenum) or Eimeria ten ella (restricted to the caeca). The local immune response was measured as the specific antibody levels in the supernatants of intestinal fra gments (duodenum and caecum) maintained in culture for 16 h at 41 degr ees C, 5% CO2, 95% air. Specific IgM was detected 1 week after E. acer vulina infection, and the specific IgA and Ige contents of the duodenu m and caecum were significantly elevated (P < 0.001) after 2 weeks. Th e intestinal specific IgG content was raised. E. tenella infection res ulted in specific IgA only in the parasitized area during the second w eek post-infection (P < 0.05). Specific IgM and IgG were both detected in the duodenum and caecum, respectively, 1 and 2 weeks p.i. Producti on of parasite-specific immunoglobulins was always significantly highe r in the parasitized than in the unparasitized areas (caeca for E. ace rvulina, duodenum for E. tenella). This ex vivo culture assay of intes tinal fragments used to measure the mucosal immune response of intesti nal areas showed a significant production of specific IgA and IgM. In addition, high levels of Ige were also measured. The role of this spec ific IgG in Eimeria infection remains to be determined. (C) 1997 Austr alian Society for Parasitology. Published by Elsevier Science Ltd.