PRELIMINARY RESULTS ON INTERSEXUAL DIFFERENCES IN GENE EXPRESSION OF CHEMOKINE K203 IN MONONUCLEAR CELLS OF CHICKEN

摘要

Sex steroid levels increase during sexual maturation and cause alterations in many physiological and morphological traits. Some of these changes may be connected with age-dependent and intersexual differences in the immune system. This topic is still insufficiently understood, especially in avian species, partially due to methodological limitations. In this study we measured the gene expression of proinflammatory cytokines (IL-1 beta, IL-6, IL-18) and chemokines [K60 (IL-8-like chicken chemokine - CXCLi1), CAF (IL-8-like chicken chemokine - CXCLi2), and K203] in mononuclear cells isolated from blood and spleen after in vitro stimulation with lipopolysaccharide (LPS). Samples were collected from chickens at two ages (from pullets before sexual maturity and from sexually mature egg-laying hens). After LPS stimulation, a substantial increase was recorded in the gene expression of IL-6 and K203. All other measured genes were expressed at low levels in mononuclear cells irrespective of cell sources. We found a trend toward intersexual differences in K203 expression, but the expression of other cytokines and chemokines did not differ between the two sexes. The effect of stimulation was more pronounced in monocytes than in spleen macrophages, mainly in IL-6, IL-1 beta and K203 gene expression. Our findings represent a basis for further studies on the effects exerted by sexual hormones on the immune phenotype of birds.