Objectives　To study of the method for isolation and transplantation of mouse islets. Methods　The method for isolation of mouse islets described by Gotoh G was modified. The solution of digestion was injected not through the common bile duct but through gallbladder. Soybean trypsin inhibitor and BSA were added into the digestive and Ficoll separation solutions. Results　The yield of islets was increased from 41.7±13.2 to 266.5±32.1(P<0.01). Islet viability was more than 95!%. Among the purified islets, there was no exocrine tissue but few ductal fragments. Conclusions　By the improved method, digestive solution could be injected into pancreas without inverted microscope, which made manipulation easier and more successful. Having avoided the digestive effect of trypsin on islets, the yield of islets was increased and good repetitiousness was obtained.

Objectives To study the induction and tolerance properties of antigen-specific T cell anergy.Methods APC:T:B cell reactive system was established in vitro.T cell proliferation was analyzed by using 3H-TdR incorporation in the blockade of B7/CD28 with B7-1 mAb and CsA.B cell antibody production was assayed by using ELISA ResultsAntigen-specific T cell anergy can be successfuily induced by the combination of CsA and B7-lmAb in vitro.Anergic T cell can not produce IL-2.but can secrete IL4.Anergic T cells can inhibit MLR.B cell proliferation and specific antibody production.Exogenous IL-2 can prevent T celt anergic induction,but can not reverse the state of tolerance.Conclusions Antigenspecific T cell anergy could be induced by CsA-combined with B7-1 mAb,which would provide theoretical evidence for prevention of transplantation rejection.

The effect of trichosanthin on mast cell degranulation and histamine release were observed with both Alcian blue staining method and fluorescent histamine determination method. It was showed that, ① in vitro trichosanthin showed no direct effect on the mast cell degranulation and histamine release even in the presence of fresh serum; ② in vivo administration on of trichosanthin in mice could cause significant mast cell degranulation and histamine release in inflammatory situ, as shown by the decreased number of Alcian blue stained nondegranulated mast cell in the peritoneal cavities; ③ intra peritoneal injection of trichosanthin in Wistar rats could significantly increase histamine level in the whole blood, while inducing prominent exudation of protein into the peritoneal cavities; ④ the supernatant of peritoneal exudate lavaged 12 hours after trichosanthin injection could cause mast cell degranulation. These results implicate that, although it showed no direct effect on mast cells, trichosanthin could cause mast cell to degranulate and release histamine via in vivo activation of some soluble mast cell degranulating factors. It was discovered in further study that the depletion of complement by cobra venom factor injection revealed no effect on the production of mast cell degranulation factor, suggesting that, in normal animals, the trichosanthininduced complement activation had no significant influence on the mast cell degranulation and histamine release.

Using Campylobacter ieiuni, strain of CJ-S131 to infect KM mice. Three months after infection, we examined the function of T and B cells in infected mice. We found that(l) there were higher, level antibodies against ds-DNA, ss-DNA.(2) ConAinduced suppressor cell activity was decreased and the ratio of Th/Ts was increased (3) The formation of PFC and lymphocyte transformation induced by LPS.PHA and ConA were increased. (4) The DTH reaction also was increased. The results mentioned above indicated that chronic infection of CJ-S131 would induce autoimmunity in KM mice.The ineffitiency of Ts cell function could be related to the hyperactivity of Th and B cells.

The KM mice(8=week-old,female)were immunized,i.p.,once a week,with outer membrane protein of ampylobacter jejuni S131.The mice were killed 12 weeks after the first injection.Serumof each mouse was collected or detecting of autoantibodies against double strained DNA,singlestrained DNA and total histones by ELISA ethod.These autoantibodies detected were inducedsuccessfully when the dose was 120-00?g/time/mouse.There was a good relation between dose andeffect.So our experimental odel provided an useful method and a novel pathway to explore theetiology and mmunological mechanisms of autoimmune diseases on molecular level.In addition,among hese three kinds of autoantibodies,the level of anti-histone antibodies was the highest and hetime it went up was the earliest,this indicated the potential significance for clinic in arlier iagnosisof some autoimmune diseases.

The immunosuppressive effect of supernatant of the cultured tumor cells, including breast adenocarcinoma ( MCF-7, MDA-453 ), gastrocarcinoma ( MKN-45 ), cervical cancer ( Hela ) and ovarian cancer ( 3AO ), was studied by MTT assay. The results showed that the supernatant of tumor cell culture suppressed the proliferation of lymphocytes activated with PHA. The supernatant of cultured tumor cells, except that of cultured MDA-453 cells, also suppressed the cytotoxic activity of LAK cells. It is suggested that there are immunosuppressive factors in the supernatant of tumor cell culture. But the immunosuppressive effect of supernatant derived from the cultured tumor cells treated with sodium phenylacetate that is a noncytotoxic differentiation inducer on the proliferation of lymphocytes activated with PHA and the cytotoxic activity of LAK cells , was decreased significantly. It indicates that sodium phenylacetate could decrease the immunosuppressive factors derived from tumor cells.

Sodium phenylacetate can induce differentiation of tumor cells and has been approved as a drug for the treatment of adults with cancer. In order to explore the immunological mechanism of its antitumor effect, the influence of sodium phenylacetate on HLA class I and II molecule expression in various human tumor cell lines, including breast adenocarcinoma (MCF-7.MUA-453), gastrocarcinoma(MKN-28,MKN-45), ovarian cancer(3AO) and cervical cancer(Hela), was studied with ELISA. The result showed that HLA class II molecule was absent from the surface of MCF-7 cells, but they could be induced after 7 days of continued treatment with sodium phenylacetate. Sodium phenylacetate was found to increase HLA class I molecule expression on the surface of MCF-7 cells, HLA class 1 and II molecule expression on the surface of MDA-453、 MKN-28、 MKN-45、 Hela and 3AO cells. The effect of sodium phenylacetate on HLA class I molecule expression in tumor cells is dose-and time-dependent.

A crucial role in eliciting anti-tumor immunity of costimulatory molecule CD80(B7-1) has been demonstrated by animal experimental studies.In this paper, CD80 expression in human tumor cell lines and EBV-transformed B cell was detected using RT-PCR and FACS methods. The results showed that CD80 expression of Raji and EBV-transformed B cell was positive but that of 3AO,MCF-7,MDA-453,MKN-45, Hela was negative. We have constructed retroviral vector CD80-pLN,transfected package cell PA317, screened high titer rctrovirus supernatant then infected human tumor cell lines and gained CD80 positive tumor cell clones. With pre-and post-CD80-transfected human breast carcinoma cell line MDA-453,the upregulated expression of ICAM-I, HLA class I molecule was observed, but the expression of HLA class II molecule wasn't changed.

To study the induced condition and characteristics of T cell anergy in vitro. Methods: Anergic Tcell was induced by combination of B7-1 mAb and cyclosporin A (CsA) in vitro, cytokine gene of anergic T cells was detected by RT-PCR. Results: T cell anergy was antigen-specific. The state of T cell anergy can be reversed by PHA, CD3 mAb and PMA plus A23187. IL-2 can prevent the induction of T cell anergy, but it can not reverse the state of un-responsiveness. IL-2 and IFN mRNA can not express in anergic T cells. In contrast, IL-4 and IL-10 mRNA were detectable. Conclusion: T cell anergy can be induced in vitro , cytokine profile of anergic T cells deviated to Th2-like phe-norype.

BACKGROUND:Human-mammal chimeric liver chimera has been a vital significance for the proliferation and differentiation of bone marrow mesenchymal stem cells.
OBJECTIVE:To establish an animal model of human-rhesus chimeric liver using adult bone marrow mesenchymal stem cells.
METHODS:Adult bone marrow mesenchymal stem cells were isolated, purified and cultured for the sixth generation. The number of bone marrow mesenchymal stem cells was no less than 5×108. Bone marrow mesenchymal stem cells labeled with green fluorescent protein were transplanted into the liver of the embryo rhesus with pregnancy of 10 weeks under guided by type-B ultrasound. At the 1st and 3rd months of birth, the liver tissue of the infant rhesus was taken for biopsy. After routine pathological section, histological specimens were observed under fluorescence microscope to confirm if there were adult bone marrow mesenchymal stem cells positive for green fluorescent protein and their distribution, and detected by immunohistochemical staining to identify if human albumin expressed in the liver of infant rhesus.
RESULTS AND CONCLUSION:Fluorescence microscope observation indicated that at the 1st and 3rd months after birth, there were surviving bone marrow mesenchymal stem cells derived from human with green fluorescence in the liver of infant rhesus, and these cells migrated to form more concentrated distribution. The immunohistochemical results demonstrated that functional liver cells expressing human albumin were observed in the liver of infant rhesus at the 1st and 3rd months after birth, and their distribution was in accordance with bone marrow mesenchymal stem cells with green fluorescence. Human-rhesus chimeric liver can be established using adult bone marrow mesenchymal stem cells, which can generate functional liver cells in the liver of infant rhesus.