Immunological basis of differences in disease resistance in the chicken

Abstract

-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. The diversity of these proteins that mainly is due to an intrinsic polymorphism of the genes causes phenotypic variation in disease resistance. The well-known linkage of MHC polymorphism and Marek's disease resistance difference represents a classic model revealing immunological factors in resistance differences and diversity of mediator molecules. The molecular bases in any resistance variation to infectious pathogens are vaguely understood. This paper presents a review of the major immune mediators involved in resistance and susceptibility to infectious diseases and their functional mechanisms in the chicken. The genetic interaction of disease resistance with production traits and the environment is mentioned. et les interactions entre les cellules présentant des antigènes, les cellules T et B, sont cruciales. Cela se produit à travers un réseau de protéines médiatrices telles que les molécules du complexe majeur d'histocompatibilité (CMH), les récepteurs des cellules T, les immunoglobulines et les protéines sé-crétées telles que les cytokines et les anticorps. La diversité de ces protéines, qui est surtout due au polymorphisme intrinsèque des gènes, entraîne une variation phénotypique dans la résistance aux maladies. Le lien bien connu entre le polymorphisme du CMH et les différences dans la résistance à la maladie de Marek représente un modèle classique révélant les facteurs immunologiques dans les différences de résistance et la diversité dans les molécules médiatrices. Les bases moléculaires impliquées dans toute variation de résistance aux pathogènes infectieux sont à peu près comprises. Cet article présente une synthèse sur les principaux médiateurs de l'immunité impliqués dans la résis-tance et la sensibilité aux maladies infectieuses chez le poulet et leurs mécanismes fonctionnels. L'interaction génétique entre la résistance aux maladies et les traits de production et l'environnement est mentionnée.

Mycobacteriosis in naturally infected ring-neck doves (Streptopelia risoria): investigation of the association between feather colour and susceptibility to infection, disease and lesions type

“…These data are consistent with epidemiological and genetic studies showing immune response polymorphism to mycobacterial infections in humans and other mammals (Bellamy, 2005;Dorman et al, 2004;Barthel et al, 2000;Pan et al, 2005;Di Pietrantonio & Schurr, 2005) and in different strains of chickens (Hu et al, 1997;Bacon et al, 2000). Specific genes that have been associated with differing immune responses to mycobacterial infections include those that code for the major histocompatability receptors, cytokines, T-cell receptors, immunoglobulins and NRAMP1 (Zekarias et al, 2002).…”

A putative quantitative trait locus on chromosome 20 associated with bovine pathogenic disease incidence1,2

“…Animals rely on the major histocompatibility complex to provide immunity against infectious diseases (Zekarias et al, 2002). However, little is known about the regulatory mechanisms of this complex.…”

Endogenous expression of thermo-sensitive ion channels TRPV1 and TRPV4 in immune tissues of avian species (duck, Anas platyrhynchos)

“…In the context of immunity development, both B-and T-lymphocytes are the principal cells responsible for both humoral and cell-mediated immunity (Zekarias et al, 2002). Lymphocyte function is regulated by a complex network of ion channels and transporters regulating calcium signaling which function as second messenger to regulate crucial lymphocyte functions such as cytokine production, differentiation and cytotoxicity.…”