Submitted to: Feedinfo.com
Publication Type: Trade Journal
Publication Acceptance Date: 2/28/2002
Publication Date: N/A
Interpretive Summary: During the first week of life after hatching, the immune system of the baby chick is not very good at fighting bacterial infections such as Salmonella. We have found chemicals in the body of adult chickens called cytokines. These chemicals control the way baby chicks fight infections. In this paper, we are reviewing the experiments done in our lab showing that when we give these cytokines to baby chicks they are immediately protected against bacterial infections because of an improved ability to fight the infection. The results of these experiments are important to the pharmaceutical industry in the United States because it shows that we can stimulate the baby chick's cells of the immune system. This report was also written because of the interest of the poultry industry in protecting chickens from disease.
Technical Abstract: Cytokines are soluble, low molecular weight polypeptides and glycopeptides produced by a broad range of cell types of hematopoietic and nonhematopoietic origin that have suppressive or enhansive effects on cellular proliferation, differentiation, activation, and motility. Like hormones, cytokines mediate cellular responses through autocrine, paracrine, and endocrine activities. Both inflammatory responses and specific immune responses to invasive microbes, which were evolved to protect the host from pathogens, are controlled by a complex network of cytokines. As regulators of the initiation and maintenance of host defenses, cytokines ultimately determine the type of response generated and the effector mechanisms generated to mediate resistance. As effector molecules, cytokines are produced transiently and locally to control the amplitude and duration of the response. Likewise, excessive or insufficient production of a cytokine or cytokines may contribute significantly to the pathophysiology of disease. Therefore, cytokines play pivotal, but paradoxical roles in both in the regulation of inflammation and immunity. The use of exogenous cytokines against infectious agents in poultry medicine has centered on: (a) their use as adjuvants for vaccines, (b) their direct effects on inducing protection against infections and/or the undesired effects of immune responses elicited by pathogens, and (c) their ability to stimulate the ontogeny and activation of neonatal host defenses. This monograph will review what has been reported about the use of cytokines in poultry in these three main areas.