The potential of avian cytokines as immunotherapeutics and vaccine adjuvants / 生物工程学报

ABSTRACT

With the imminent and widespread ban of the use of antibiotic feed additives and chemical antimicrobials in food production animals, alternative measures need to be sought to ensure that the livestock industry will not be adversely affected. Cytokines are proteins that control the type and extent of an immune response following infection or vaccination. They therefore represent excellent naturally occurring therapeutics. The identification, cloning and characterisation of cytokine genes in chickens have lagged somewhat behind similar work in mammals. Progress in isolating chicken homologues of mammalian cytokines has also been slowed by the generally low level of sequence similarity. Chicken cytokine genes that have been cloned to date include ChIFN-gamma, ChIL-1beta, ChIFN-alpha, ChIL-15, ChIL-18, ChIL-8, ChIL-2, ChIL-6, ChIL-16, SCF, MGF, TGFbeta, Lymphotactin, MIP-1beta, CXC and CC chemokines, so the use of cytokines in poultry has become more feasible with the discovery of a number of avian cytokine genes. The delivery methods for chicken cytokine are of prime importance and are required to be safe, easy to administer and cost-effective. Live viral vectors such as fowl adenovirus (FAV) expressing cytokine genes can be delivered via drinking water or aerosol sprays, making it very easy to administer. Since the immune system of chickens is similar to that of mammals, they offer an attractive model system to study the effectiveness of cytokine therapy in the control of disease in livestock. This review focus on the recent advances made in avian cytokines, with a particular focus on their assessment as therapeutic agents and vaccine adjuvants.