Immunogenomic Approaches to Study Host Immunity to Enteric Pathogens

Abstract

With increasing consumer demands for safe poultry products, effective control of disease-causing pathogens is becoming a major challenge to the poultry industry. Many chicken pathogens enter the host through the gastrointestinal tract, and over the past few decades, in-feed antibiotics and active vaccination have been the 2 main mechanisms of disease control. However, increasing public concerns are prompting government regulations on the use of growth-promoting drugs in animal production, and the ability of current vaccines to protect against emerging hypervirulent strains of pathogens is becoming an issue. Therefore, there is a need to develop alternative control strategies against poultry pathogens of economic importance as well as to carry out basic research to enhance understanding of host-pathogen interactions at local sites of infection. Effective control strategies against pathogens can only be accomplished by comprehensive analysis of the basic immunobiology of host-pathogen interactions. Recent sequencing of the poultry genome and the availability of several tissue-specific cDNA microarrays are facilitating the rapid application of functional immunogenomic technologies to poultry disease research. Studies using functional genomic, immunology, and bioinformatic approaches have provided novel insights into disease processes and protective immunity to chicken pathogens. In this review, we summarize recent published literature concerning the host response to Eimeria and Salmonella infections with emphasis on our studies using immunogenomic tools to investigate and characterize the mechanisms of avian immunity to these mucosal pathogens. The results clearly indicate that this immunogenomic approach will lead to increased understanding of immune responses to infectious agents that will enable the development of effective prevention strategies against mucosal pathogens.

Downregulation of Chicken Interleukin-17 Receptor A during Eimeria Infection

“…This pathogen enters the small intestine and is carried to various organs, including the spleen and liver (46)(47)(48). Expression of chicken IL-17 transcript increases in the cecum during Salmonella enterica serovar Enteritidis infection (20,49).…”

Efficacy of turmeric (Curcuma longa) and garlic (Allium sativum) on Eimeria species in broilers

“…Historically, the severity of experimental Eimeria infection in chickens has been assessed by loss of body weight gain, excretion of fecal oocysts, and the presence of intestinal lesions [45]. These disease parameters reflect host immunity status in avian coccidiosis [46]. The the present study was planned to evaluate an in-vitro efficacy of different concentrations of turmeric and garlic powders on mixed Eimeria oocysts vitality and application of the most effective concentrations in vivo on the experimentally infected with mixed Eimeria species broiler chicks.…”

Mhcpolymorphisms fail to explain the heritability of phytohaemagglutinin-induced skin swelling in a wild passerine

“…Genetic contributions to the phenotypic variability of parasite resistance and immune response have mainly been demonstrated in domestic or laboratory species (Lillehoj et al 2007). The genetic variation underlying those traits is however harder to detect in natural populations (Kilpimaa et al 2005), in part because of environmental variance (Sorci et al 1997), but also because fitness traits have lower heritabilities than non-fitness traits (Mousseau & Roff 1987).…”