Marek's disease (MD) virus (MDV) has provided an important model to study immune responses against a lymphoma-inducing herpesvirus in its natural host. Infection in chickens starts with a lytic infection in B cells, followed by a latent infection in T cells and, in susceptible birds, T cell lymphomas develop. Non-specific and specific immune responses are important for the control of virus infection and subsequent tumor development. Interferon-γ and nitric oxide are important for the control of virus replication during the lytic phase of infection and are also important to prevent reactivation of MDV replication in latently infected and transformed cells. Cytotoxic T cells (CTLs) are the most important of the specific immune responses in MDV. In addition to antigen-specific CTL against MDV proteins pp38, glycoprotein B (gB), Meq, and ICP4, ICP27-specific CTL can also be detected as early as 6 to 7 days post infection. The epitope for gB recognized by CTLs from P2a (MHC: B19B19) chickens has been localized to the Eco47III-BamHI (nucleotides 1515-1800) fragment. A proposed model for the interactions of cytokines and immune responses as part of the pathogenesis of MD is discussed.
Bibliographical noteFunding Information:
The authors want to thank Dr. S. Kaplan, Ms. Carrie Markowski and Ms. Laura Stenzler for their suggestions and critical reading of the manuscript. New data reported in this paper are based upon work supported by the Cooperative State Research, Education, and Extension Service, U.S. Department of Agriculture, under agreement numbers 98-35204-6425 and 95-37204-2237 and USDA Regional Research NE-60.
- Antiviral immunity
- Cell-mediated immunity
- Macrophages, Cytotoxic T cells
- Marek's disease
- Nitric oxide