Adoptive transfer of infectious bronchitis virus primed alpha beta T cellsbearing CD8 antigen protects chicks from acute infection

Infectious bronchitis virus (IBV) infection and associated illness may be d ramatically modified by passive transfer of immune T lymphocytes. Lymphocyt es collected 10 days postinfection were transferred to naive chicks before challenge with virus. As determined by respiratory illness and viral load, transfer of syngeneic immune T lymphocytes protected chicks from challenge infection, whereas no protection was observed in the chicks receiving the M HC compatible lymphocytes from uninfected chicks. Protection following admi nistration of T lymphocytes could be observed in chicks with three distinct MHC haplotypes: B-8/B-8, B-12/B-12 and B-19/B(19)g. Nearly complete elimin ation of viral infection and illness was observed in chicks receiving cells enriched in alpha beta lymphocytes. In contrast, removal of gamma delta T lymphocytes had only a small effect on their potential to protect chicks. T he adoptive transfer of enriched CD8(+) or CD4(+) T lymphocytes indicated t hat protection was also a function primarily of CD8-bearing cells. These re sults indicated that alpha beta T lymphocytes bearing CD8(+) antigens are c ritical in protecting chicks from IBV infection. (C) 2000 Academic Press.