A mRNA PCR for the diagnosis of feline infectious peritonitis.

A reverse transcriptase polymerase chain reaction (RT-PCR) for the detection of feline coronavirus (FCoV) messenger RNA in peripheral blood mononuclear cells (PBMCs) is described. The assay is evaluated as a diagnostic test for feline infectious peritonitis (FIP). It is based on a well-documented key event in the development of FIP: the replication of virulent FCoV mutants in monocytes/macrophages.

Exchange of the C-terminal part of VP3 from very virulent infectious bursal disease virus results in an attenuated virus with a unique antigenic structure.

Infectious bursal disease virus (IBDV) is the major viral pathogen in the poultry industry. Live attenuated serotype 1 vaccine strains are commonly used to protect susceptible chickens during their first 6 weeks of life. Wild-type serotype 1 IBDV strains are highly pathogenic only in chickens, whereas serotype 2 strains are apathogenic in chickens and other birds.

Immunological basis of differences in disease resistance in the chicken.

Genetic resistance to diseases is a multigenic trait governed mainly by the immune system and its interactions with many physiologic and environmental factors. In the adaptive immunity, T cell and B cell responses, the specific recognition of antigens and interactions between antigen presenting cells, T cells and B cells are crucial. It occurs through a network of mediator proteins such as the molecules of the major histocompatibility complex (MHC), T cell receptors, immunoglobulins and secreted proteins such as the cytokines and antibodies.