Differential Expression Of Adaptive Immunity Related Genes In Lampetra Japonica's Lymphocyte-like Cells

To isolate and purify peripheral blood lymphocyte-like cells from the arctic lamprey, Lampetra japonica, centrifugation on Ficoll-Paque were performed and a uniform population of leucocytes containing lymphocyte-like cells with the mixture of Ficoll-Urografin solution at proportion of 1. 092 was yielded. With the FSC and SSC character of the cells on flow cytometer,Lymphocyte-like cells were separated successfully, the purity was 95.68%; about 2.4×106 lymphocyte-like cells could be purified from 1 ml peripheral blood. Under TEM, Lymphocyte-like cells are round or ellipse without microvillus. there are mitochondrion with cristae, rough endoplasmic reticulum,dissociated ribosome and vacuole in their cytoplasm.The lymphocyte heterogeneity is analyzed by the experiment of cell multiplication. The result of ANAE reveals that there is no positive reddish brown grain in the leucocytes of L. japonica. Then, the studies on the capacities of immune responses of lymphocytes in peripheral blood of L. japonica to PHA and SPA with the active determine of MTT also indicated that there is no clear differentiation of T and B lymphocyte in the leucocytes of L. japonica. But this result scantly analyzed the aspect from cytomorphology and histochemistry of the lymphocyte heterogeneity of L. japonica, presuming that there is maybe no clear differentiation of T and B lymphocyte in the leucocytes of L. japonica.The research of the adaptive immune gene expression in lymphocyte like cell of L. japonica,has been studied using RFDD-PCR. Gene expression profile of immunized adult has been constructed covering 1683 fragments of immunized lamprey, among these fragments, 97(5.76%) sequences of immunized and normal showed differences in abundance or presence. These different expressed gene fragments are analyzed and blast for homology. There are 64 of 97 different expressed gene fragments have got biological function information from homology sequence with tblastx in NCBI. These functions were classified into 8 different functional categories, include primary metabolize,protein synthesis,transcript,energy metabolism,cell structure,signal transduction,cell apoptosis,immune defence. There have 13 immune defense function genes, approximately 20.3% of the differences. And selected two specific candidate genes related to immune VLR, has the very high homologous similarity with the sea lamprey's VLR gene. At the same time get some may be new candidate gene fragments, pending further study confirmed. Through the analysis of different segments to infer the mechanism of agnathan vertebrates' adaptive immune system, and to provide clues for further study.