Natural mechanisms of controlling lymphotropic herpesvirus infection (Marek's disease) in the chicken.

Four categories of natural resistance phenomena against Mareks disease in chickens, i.e., maternal antibody, age resistance, genetic resistance, and natural immunization, are described. In nature, these forms of resistance probably act in concert through comlex interrelationships. The mechanisms are not well understood but include humoral immunity (maternal antibody), cell-mediated immunity, and possibly other mechanisms. The possible role of newly discovered tumor-specific antigens in cell-mediated immunity against Marek's disease lymphomas is discussed.