Study On The Lymphocytes Of Japanese Flounder, Paralichthys Olivaceus

Teleosts possess a well-developed immune system, which resembles the mammalian immune system. In mammals, T lymphocytes derive their name from their site of maturation in the thymus. Lymphocyte heterogeneity, particularly the participation of T-like lymphocytes in fish immunity, is now well established. T-like cells were defined as sIg super(-)cells which proliferate in the presence of specific mitogens for mammalian T lymphocytes (Con A and PHA). The degree of diversification and the participation in the the cell-mediated immunity of the lymphocytes in fish are still under doubt. In this research, we are focus on the separation, recognition and molecular marker of T-cell.We also detected participation of T-cell in the the cell-mediated immunity and the T-cell dynamics in the disease defense process of flounder. The immunoactivity analysis of lymphocytes in Paralichthys olivaceusAlthough the heterogeneity of T/B lymphocytes in fish is now well established, recognition of the cells that are responsible for their functions in the fish specific immune responses is still difficult, as classification of leukocytes primarily relies on morphological parameters. Peripheral blood lymphocytes of Japanese flounder were isolated by the mixture at density 1.083 centrifugation. The lymphocytes were than separated into 2 population, adherent and nonaderent cell, according to their adherence to nylon wool, cell surface structure, acid α-naphtyl acetate esterase(AENE) and acid phosphatase(ACP) activity in those two subpopulation indicated that the existence of T/B like lymphocytes in flounder and the relative ratio of the AENE and ACP positive cells in the immunological related organs or bloods was used as one of the criteria for determining the immunological function in different tissues ,developing stage in flounder. The different AENE and ACP activities of lymphocytes also showed the origin and migration of lymphocytes subpopulation.In vitro studies on lymphocyte population in Paralichthys olivaceusThe lymphocytes transplant test To determine the effect of foreign antigen and mitogen on immune function of T lymphocytes of Paralichthys oliveaceus,the lymphocytes obtained from peripheral blood, spleen and head kidney of Paralichthys oliveaceus were cultured in vitro, their proliferative was determined with MTT. The results showed that within the suitable temperature, at the comparatable low temperature the proliferation of cultured cells were decreased. The nonspecific lymphocyts proliferation of peripheral blood and spleen was higher than that of the lymphocyte from head kidney. The specific lymphocytes proliferation of peripheral blood were higher than those of head kidey and spleen,and the head kidney lymphocyte proliferation was higher than spleen's. Injection increased the proliferation of lymphocytes of Paralichthys oliveaceus.Analysis of IL-2-like factor in lymphocyte culture supernatant Interleukin-2 is the major immunoregulatory molecule produced by helper T cell and other related cells. It can stimulate the NK cell and other cell such as monocyte's activities and plays an important role in transcript,translation, signal transduction and immunological regulation of nevous system.. Interleukin-2(IL-2)-like factor was detected by using monoclonal antibody against human IL-2 in the supernatant of plant haemoglutinin( PHA )-stimulated lymphocyte culture from peripheral blood, spleen and head kidney. The quantities of IL-2-like factor in the supernatant from different tissues were quite different. The IL-2 activity were found both in mouse thymocyte proliferation assay and flounder head kidney lymphocyte proliferation assay. The cross-reaction between the lymphocytes of flounder peripheral blood and CD25(IL-2R)was detected with flow cytometry and shown that the percentage of CD25-positive cell in peripheral blood is 7.74±0.67%.Surface marker of olive flounder, Paralichthys oliveaceus.Study of surface antigen on lymphocyte of Paralichthys oliveaceusThe lymphocyte surface antigen were...