The cellular immune response in the tracheal mucosa to Mycoplasma gallisepticum in vaccinated and unvaccinated chickens in the acute and chronic stages of disease

Abstract

Mycoplasma gallisepticum causes a lymphoproliferative response in the tracheal mucosa of infected birds. The studies reported here aimed to determine, using immunohistochemical and immunofluorescent staining, which lymphocyte subsets were infiltrating the mucosa during the acute and chronic phases of disease and to determine whether these subsets differed in birds that had been vaccinated with strain ts-11. In vaccinates there was no detectable infiltration of T or B lymphocytes between 1 and 6 weeks after infection with a virulent strain. Unvaccinated birds had an initial influx of CD8+TCR - lymphocytes at 1 week, with the numbers decreasing over the next 5 weeks. CD8+TCR+ cells increased o..