Volume 53 (2003) Issue: 2003 No#5-6

STUDY OF THE DISTRIBUTION OF CD3-T LYMPHOCYTES IN CAECA OF CHICKENS EXPERIMENTALLY INFECTED WITH EIMERIA TENELLA

Author(s): Ilić Tamara, Knežević Miljana, Dimitrijević Sanda, Nešić V, Aleksić-Kovačević Sanja

Keywords:chickens, coccidiosis, E. tenella, immunohistochemistry

An immunohistochemical study of caecum tissue samples was performed on chickens that had been infected with E. tenella when 14 days old. Using antibodies of rabbits against T-CD3 lymphocytes (DAKO EPOS N0U 0026) and applying the direct peroxidase method, CD3 positive lymphocytes in caeca were marked. This lymphocyte subpopulation , was localized in the lamina epithelial mucosa of the caecum. Increased immunoreactivity in the lamina epithelial mucosa of the caecum and stroma of the lamina propria mucosa, was observed already on the first day after infection with E. tenella, with the greatest intensity occuring between the third and fifth day. These findings demonstrate the existence of an early immunological response to infection caused by E. tenella, that is cell mediated, which is one of its most important characteristics