Development and characterization of mouse monoclonal antibodies reactive with chicken CXCLi2.

Interleukin-8(IL-8)/CXCL8 is a CXC-family chemokine that attracts lymphocytes to sites of tissue damage and plays a role in the inflammatory response and wound healing. Chicken chemotactic and angiogenic factor was referred to as chCXCLi2 and has been studied as one of human CXCL8 homologue for more than 20 years. However, no monoclonal antibodies (mAbs) that specifically detect chCXCLi2 have been developed. Here, we developed and characterized mouse mAbs against chCXCLi2 to define its immunological properties. Two mouse mAbs against chCXCLi2 were generated and confirmed to display specific binding with not only recombinants, but endogenous chCXCLi2 by Western blot analysis, ELISA, and immunocytochemistry. Inhibition of chCXCLi2-induced chemotactic activity on peripheral blood lymphocytes, proliferation of chicken macrophage cells and expression of alpha smooth-muscle actin in chicken embryonic fibroblast cells by antibodies indicate that these antibodies are capable of blocking chCXCLi2 bioactivity. These chCXCLi2 mAbs will be useful reagents for future investigations of inflammation in poultry.

Calcium Montmorillonite-Based Dietary Supplement Attenuates Necrotic Enteritis Induced by Eimeria maxima and Clostridium perfringens in Broilers.

Necrotic enteritis (NE) is a poultry disease caused by Clostridium perfringens and characterized by severe intestinal necrosis. The incidence of avian NE has been progressively increasing following the removal of antibiotics from poultry feed. We evaluated the effect of diets supplemented with the thermally-processed clays, calcium montmorillonite (CaMM) on clinical signs, immunopathology, and cytokine responses in broiler chickens using an experimental model of NE consisting of co-infection with Eimeria maxima and C. perfringens. In Trial 1, Ross/Ross chickens were fed from hatch with a normal basal diet or a CaMM-supplemented diet with or without a fermentable fiber, an organic acid, and/or a plant extract, and co-infected with E. maxima and C. perfringens under conditions simulating clinical infection in the field. Chickens fed a diet supplemented with CaMM plus a fermentable fiber and an organic acid had increased body weight gain, reduced gut lesions, and increased serum antibody levels to C. perfringens α-toxin and NetB toxin compared with chickens fed the basal diet alone. Levels of transcripts for interleukin-1ß (IL-1ß), IL-6, inducible nitric oxide synthase, and tumor necrosis factor-α superfamily-15 were significantly altered in the intestine and spleen of CaMM-supplemented chickens compared with unsupplemented controls (p<0.05). In Trial 2, Cobb/Cobb chickens were fed an unsupplemented diet or a diet supplemented with CaMM or Varium®, each with a fermentable fiber and an organic acid, and co-infected with E. maxima and C. perfringens under subclinical infection conditions. Compared with unsupplemented controls, broilers fed with CaMM plus a fermentable fiber and an organic acid had increased body weight gain, and reduced feed conversion ratio, mortality, and intestinal lesions, compared with chickens fed an unsupplemented diet (p<0.05). Dietary supplementation of broiler chickens with CaMM plus a fermentable fiber and an organic acid might be useful to control avian NE in the field.

Genome sequence of Lactobacillus salivarius GJ-24, a probiotic strain isolated from healthy adult intestine.

The draft genome sequence of Lactobacillus salivarius GJ-24 isolated from the feces of healthy adults was determined. Its properties, including milk fermentation activity and bacteriocin production, suggest its potential uses as a probiotic lactic acid bacterium and start culture for dairy products.