Development Of Peripheral Immune Organs,Age-related Changes Of IL-2 And IL-21 In Chinese Yellow Quail

The aim of this study was to investigate the histological features of the Harderian gland,spleen and cecal tonsil in different ages of Chinese yellow quail,and to find out the histological dynamics of Harderian gland,spleen and cecal tonsil with different age.The law of change provides a scientific basis for the study of the development and changes of peripheral immune organs in Chinese yellow quail,and the distribution and changes of IL-2 and IL-21 in the cecal tonsils,Harderian gland and spleen of Chinese yellow quail.Regularity,the changes of IL-2 and IL-21 expression were increased with age,and the relationship between IL-2 and IL-21 and the proliferation and development of T and B cells and their effects on immune organ development were analyzed.In this experiment,90 healthy Chinese yellow quail of 0,1,2,3,4,5,6,10,14,18,22,26,30,34,and 38 weeks old were selected and divided into 15 groups.Six animals were used for HE staining,electron microscopy and SABC immunohistochemical staining to study the changes of morphological structure and IL-2 and IL-21 in the spleen,cecal tonsil and Harderian gland of Chinese yellow quail.The results of light microscopy and electron microscopy showed that the development of peripheral immune organs of Chinese yellow-feathered quails varies with age: it develops gradually to maturity with age,and remains basically unchanged after that.That is,the Hard's gland develops rapidly at the age of 0-4 weeks.Quails' body weight,absolute weight of Hard's gland,index,length and width,and various microscopic measurement indices are gland diameter,lobular diameter,duct diameter and trabecular straightness.The diameters of spleen and cecum tonsils were growing rapidly at the age of 0-6 weeks,and the absolute weight,index,length and width of organs,as well as various micrometric indices,such as splenic nodules,ellipsoids and periarterial lymphatic sheaths of spleen,diameter and area of germinal center,mucosa of cecum tonsils,were kept constant at the age of 10-38 weeks,while those of spleen and cecum tonsils were developing rapidly at the age of 0-6 weeks.The height,the depth of intestinal gland and the height of plica all showed an increasing trend.The 10-38 weeks old was the maturity duration.The above indicators gradually decreased,but the decreasing trend was small,and the overall difference was not significant.The results of immunohistochemistry showed that IL-2 and IL-21 positive cells were brown or brown in the peripheral immune organs,mainly round or oval,and no negative products appeared in the negative control sections.Among them,in the spleen,IL-2 and IL-21 positive cells are mainly distributed in the white pulp,and there are also distributions in the red pulp.Among them,IL-2 is mainly distributed in the lymphatic sheath around the artery and the lymphatic sheath around the ellipsoid,and the positive cells are in the marginal area.And the red pulp is scattered,IL-21 positive cells are mainly distributed in the splenomegaly and its surrounding,periarterial lymphatic sheath and spheroidal lymphatic sheath;in the cecal tonsil,IL-2 positive cells are mainly distributed in the bottom of the mucosa and the middle The germinal center of the layer and its surroundings are distributed in the gut and its surroundings,the submucosal lamina propria and the submucosa.The IL-21 positive cells are mainly distributed in the submucosal submucosa,submucosa and intestinal glands.It is distributed around the mucosal folds.In the Harderian gland,IL-2 positive cells are mainly distributed between the ducts,and a small part is distributed around the acinus and around the main duct lumen.IL-21 positive cells are mainly distributed in the Around the main duct lumen,a few were distributed between the ducts and acinar cells.The expression levels of IL-2 and IL-21 positive cells increased in the peripheral immune organs from 0 to 6 weeks old,both in 6 Week age It reaches the maximum and then remains basically unchanged,indicating that during the development of peripheral immune organs,lymphocytes stimulate and enrich the development of the tissue structure,and the mature tissue structure will provide a place for lymphocytes to exercise functional activities,The dynamic changes of IL-2 and IL-21 are related to the tissue structure and functional perfection of peripheral immune organs.