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

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.

Age related differences in the immune response to vaccination and infection with Mycoplasma gallisepticum.

Several studies have suggested that there are age related differences in the responses of chickens to vaccination and infection with Mycoplasma gallisepticum, but there have not been any systematic comparisons of the responses of young birds to vaccination with those of birds the same age to infection. The aim of the studies described here was to examine the immune responses of chickens between 1 and 6 weeks of age to vaccination and to infection with M. gallisepticum.

Lymphocytic infiltration in the chicken trachea in response to Mycoplasma gallisepticum infection.

A prominent feature of disease induced by Mycoplasma gallisepticum is a lymphoproliferative response in the respiratory tract. Although this is also seen in other mycoplasma infections, including Mycoplasma pneumoniae, the phenotype of the lymphocytes infiltrating the respiratory tract has not been determined. In this study, the numbers and distribution of lymphocytes in the tracheas of chickens infected with a virulent strain of M.