AIM: To explore the correlation between development of CD4~+CD25~+ regulatory T cells (CD4~+CD25~+ Tr) and thymus CD4~-CD25~+ cells. METHODS: The ratios of CD4~+CD25~+ regulatory T cells to CD4~+ T cells in thymus, spleen, lymph node and peripheral blood of mice from birth to mature and also the ratios of CD4~-CD25~+cells to CD4~-T cells in thymus were measured by flow cytometry. Purified CD4~+CD25~+ T cells and CD4~+CD25~- T cells were labeled with CFDA-SE, and then stimulated with various kinds of stimulators. RESULTS: The percentages of CD4~+CD25~+ Tr in mouse spleen, lymph nodes and peripheral blood increased gradually, but not in thymus, from day one to week 10 of the age with rapid rising from day one to week 1. The percentages of CD4~-CD25~+ cells in mouse thymus were quite high on day one after birth, and decreased rapidly from day one to week 1. Both CD4~+CD25~+ Tr and CD4~+CD25~- T cells showed no proliferation in response to ConA, while CD4~+CD25~+ Tr showed a transient enlargement of cell size. Both CD4~+CD25~+ Tr and CD4~+CD25~- T cells underwent proliferation in response to PDB plus ionomycin. CD4~+CD25~- T cells, but not CD4~+CD25~+ Tr, showed a proliferative response to the stimulation of coated anti-CD3 plus soluble anti-CD28 antibody, however, CD4~+CD25~+ Tr showed significant proliferation and CD4~+CD25~- T cells showed a stronger response in addition of high dose of IL-2. CONCLUSION: The thymus CD4~-CD25~+ cells are probably the precursor of CD4~+CD25~+ Tr during cell development.

Given its population of CCR5-expressing, immunologically activated CD4 +T cells, the gastrointestinal (GI) mucosa is uniquely susceptible to human immunodeficiency virus (HIV)-1 infection. Recent studies have shown that, as in macaques infected with simian immunodeficiency virus (SIV), intestinal CD4 +T cells are selectively and rapidly depleted in the intestine of HIV-infected patients. Depletion of intestinal CD4 +T cells occurred at all stages of infection regardless of highly active antiretroviral therapy (HAART). Here we discuss the important implications of the recent findings for our understanding of HIV pathogenesis, treatment, and vaccine design. The major significance is that it supports a simple hypothesis to explain the pathogenesis of HIV infection, that most HIV replication occurs in the intestine and that disease progression may correlate with turnover of specific cell subsets in mucosal tissues.

Objective:To study the effect of isoflavone and genistein on activation of T lymphocytes in order to develope new immuno intervention reagent.Methods:Fluorescence conjugated monoclonal antibodies and flow cytometer were used to detect the expression rate of CD69 by activated T cells in vitro in response to Phytohemagglutinin(PHA) and Phorbol 12,13 dibutyrate(PDB),with some samples pre incubated with 10,50 or 100 ?mol/L of genistein,after 2 h and 6 h of incubation in whole blood culture system.Results:After 2 h of culture,the inhibitory effect in PHA group was stronger than PDB group(P

Objective To investigate the association between the C609T polymorphism of NAD (P)H:quinoneoxidoreductase (NQO1) gene and post operative cognitive dysfunction (POCD).Methods 90 ASA Ⅰ-Ⅱ patients of 59 to 78 years old, undergoing elective hip replacement with epidural anesthesia were enrolled.All patients were given a battery of 5 neuropsychological tests before operation and seven days after operation.Patients were divided into POCD group and control group according to test results (45 patients in each group).The single nucleotide polymorphism C609T of NQO1 gene was detected using real-time PCR by Taqman probes and subjected to odd ratio assessment.Results 5 samples in control group couldn' t be used in the real-time PCR analysis due to quality control.The frequency of C/C genotype in POCD control was lower than that of control group ( 30.0% vs 11.1% ) with statistical significance ( OR = 0.292,95 % CI 0.092 ～ 0.92 1, P ＜ 0.05 ).The C/T +T/T genotype frequency was significantly higher in group POCD than in the control group(88.8% vs 70% ).Patients presented with C/T + T/T genotype showed an evidently increased risk of POCD ( OR =3.42,95% CI 1.08 ～ 10.82,P ＜ 0.05 ).The frequency of C allele of NQO1 gene in group control was 56.2%, as compared with 40% in group POCD with significance ( OR = 0.519,95% CI 0.282 ～ 0.955, P ＜ 0.05 ).The frequency of T allele of NQOI gene in control group was 43.7% ,as compared with 60.0% in POCD group( OR = 1.93,95% CI 1.047 ～3.552,P＜O.05).Conclusion The NQO1 gene single nucleotide polymorphism C609T is evidently associated with the increased risk of POCD.

AIM:To study the effects of progesterone(P4) on the maturation and immunologic function of dendritic cells(DCs) from human peripheral blood.METHODS:Cultured DCs were treated with P4 at doses of 10-7 mol/L and 10-6 mol/L.The morphologic changes were observed under the scanning electronic microscope.The immunophenotypes of DCs in control and treated groups were analyzed by flow cytometry.IL-10 and IL-12 production in culture supernatant was examined by ELISA assay.The capability of the stimulatory activity of the DCs on allogeneic T cells in mixed reaction was tested by incorporation of [3H]-TdR.RESULTS:Compared with control group,cultured DCs in the presence of P4 displayed less dendritic pseudopod,expressed low levels of MHC-II,CD40,CD80 and CD86,and exhibited weakly activity in stimulating the proliferation of allogeneic T cells.Increase in IL-10 production and decrease in IL-12 production were observed.CONCLUSION:P4 exerts negative effect on the maturation and immunologic function in dendritic cells from human peripheral blood.

AIM:To study the roles of bone marrow-derived dendritic cells from donor mouse treated with 17?-estradiol(E2)in immune tolerance induction in skin allograft.METHODS:Bone marrow-derived dendritic cells from C57 mouse as donor were cultured respectively treated with E2(E2 group).BALB/c mouse as recipient received respectively one injection of dendritic cells of E2 group,mature dendritic cell group and immature dendritic cell group intravenously.Skin transplantation was performed in the absence of immunosupression after 7 d.Mice that received PBS were served as control.The time of skin survival was observed after transplantation.Flow cytometry was used to analyze the percentage of CD4+CD25+ T cells in peripheral blood respectively before and after transplantation.RESULTS:Compared with immature dendritic cells and control group,the time of skin survival in E2 group was significantly longer(P

Objective To determine whether fetal rats exposure to isoflurane will cause postnatal learning and memory deficits,and change Bcl-2/Bax ratio in the hippocampus CA1 and retrosplenial cortex in fetal brain of rats. Methods Twenty-eight Sprague Dawley pregnant rats at gestation day 21 (E21) were randomly divided into isoflurane treatment group(n=14) and sham control group(n=14). Rats in isoflurane treatment group were ex-posed to 1.3% isoflurane in a carrying gas of 30% oxygen, balance nitrogen for 6 h in a warmed, humidified cham-ber. For sham control group,animals were treated at the same condition with only carrying gas. In behavior study,the spatial learning and memory ability at juvenile ages was determined with the Morris Water Maze(MWM). In immunohistochemistry study,changes of Bcl-2 and Bax expression in hippocampus CA1 and retrosplenial cortex in the fetus brain after isoflurane treatment at 2 hours was performed by using immunofluorecence staining.Results In the MWM training, the escape latency to platform in the place trials showed no significant difference between the two groups,but the postnatal rats in 1.3% isoflurane group showed obviously improved retention of memory by spending more percentage of time swimming in the probe quadrant as compared to the control animals ((42.33±2.31) s vs (33.2±2.15) s, t=2.21, P<0.05) in the probe test. Compared to controls, 1.3% isoflu-rane exposure for 6 h to the pregnant rats increased the intensity of Bcl-2, decreased the intensity of Bax, and sig-nificantly increased the Bcl-2/Bax ratio in the fetal hippocampal CA1 region (4.40±0. 86 vs 1.31±0.32, t=3. 378, P<0.01) and the fetal retrosplenial cortex (5.07±1.27 vs 1.47±0.48, t=2.656, P < 0.05) respec-tively. Conclusion 1.3% isoflurane exposure in pregnant rats significantly improves the spatial retention memo-ry of their rat pups at a juvenile age and increases the Bcl-2/Bax ratio in the hippocampal CA1 region and the ret-resplenial cortex in the fetal rat brains.

AIM: To investigate the inhibitory effect of quercetin on in vitro activation of T lymphocytes by polyclonal activators with CD69 expression as an activation marker. METHODS: After being separated from lymphoid nodes of a C57BL/6 mouse, the lymphocytes were exposed to polyclonal activators (PDB or Con A) with or without quercetin. Then they were harvested at 2 h, 6 h and 24 h, respectively. The expressional rates of CD69 on T lymphocytes were assessed by two-color immunofluorescent staining and flow cytometry, and the inhibitory rates of quercetin at different time points were estimated. RESULTS: Quercetin had no effect on the expressional rate of CD69 on T lymphocytes under resting states. After the stimulation with PDB or Con A, the expressional rates of CD69 on T lymphocytes in the present of quercetin (10 ?mol/L) showed significant decrease compared with those of control groups at different time points (P

AIM: To study the effect of genistein on activation and proliferation of T cells,and explore the molecular mechanism of genistein. METHODS: Fluorescence conjugated monoclonal antibodies and flow cytometry were used to detect the express of CD69 and CD25 by activated T cells in vitro in response to Concanavalin (ConA )and Phorbol 12,13-dibutyrate(PDB) or T cell proliferation stained by CFSE in response to PDB / Ionomycin or ConA. RESULTS: Genistein inhibited the expression of CD69 and CD25 in activated T cells in response to Con A in a concentration-dependent manner and in response to PDB in a high concentration. Genistein inhibited proliferation of T cells in both groups in a concentration-dependent manner. CONCLUSION: Genistein inhibited activation and proliferation of T cells in vitro in response to polyclonal stimulus,and it may hold potential as a new immunosuppressant.

AIM: To study mitochondrial mass and structural protein changes in dexamethasone (DEX)-mediated mouse thymocyte apoptosis process. METHODS: DEX-induced mouse thymocyte apoptosis model was established. Annexin V-FITC/PI double staining was used to identify apoptotic and necrotic cells by flowcytometry, JC-1 staining was adopted to test mitochondrial membrane potential (△?_m), and cellular structural protein changes were studied with CFDA-SE staining. RESULTS: By 1?10~(-6) mol/L DEX stimulation, the apoptotic rate was 51.25%?5.51% and had significantly difference from control group (12.03%?2.00%); the necrotic rate in DEX group was 30.25%?3.67% and also had significantly difference from control group (10.11%?1.11%, P