CD98 heavy chain（CD98hc）,encoded by Slc3a2,is a widely expressed vertebrate membrane protein whose functions are known as facilitating amino acid transporter and mediating integrin signaling.Little is known about it...CD98 heavy chain（CD98hc）,encoded by Slc3a2,is a widely expressed vertebrate membrane protein whose functions are known as facilitating amino acid transporter and mediating integrin signaling.Little is known about its function on T lymphocyte mediated immune response to alloantigen. Here we report that we successfully deleted CD98hc in T cells by crossing mice bearing a loxP-flanked Slc3a2 allele with those expressing Cre re-combinase in T cells（CD4-Cre+）.T cell-specific deficient of CD98hc resulted in lower responses to alloantigen stimulation in mixed lymphocyte reaction assay.Heterotopic cardiac grafting was then performed from BALB/c（H-2K<sup>d</sup>） to CD98hc<sup>lox/-</sup>CD4-Cre<sup>+</sup> /C57BL/6（H-2K<sup>b</sup>） or control littermate C57BL/6 （B6） mice.We found that all CD98hc<sup>lox/</sup>-CD4-Cre<sup>+</sup> recipients had indefinite survival（MST:】100days, n=8）.In contrast,all littermate B6 recipients suffered acute rejection[MST:（7.4±0.5）d,n=12].In addition,the survival of the skin grafts from donor BALB/c mice to more than postoperative day （POD） 100 heart-bearing tolerant CD98hc<sup>lox/-</sup>CD4- Cre<sup>+</sup> recipients was significantly prolonged[MST: （15.2±2.2）d,n =5]compared that of the B6 mice [MST:（8.2±1.3）d,n=9].In consistent with graft survival, we found that the graft infiltration cells on POD7 were fewer than that of the B6 mice by FACS and immune-staining analysis.Also chemotaxis assay data revealed that the migrated CD98hc<sup>lox/-</sup>CD4-Cre<sup>+</sup> lymphocyte were less than that of B6 in the presence of different concentration of chemokines CCL2, CCL5,and CCL2 plus CCL5.In addition,a neutralizing antibody（clone 26-24）specific against CD98hc prolonged the graft survival[MST:（13.4±2.7）d,n=8; P=0.001]in the B6 recipients after they received the BALB/c mice heart.Hence our data indicated that T cell-specific deficient of CD98hc impaired proliferate in response to alloantigens and decreased migration ability result in inducing immune tolerance after cardiac transplantation.Moreover,the application of the blocked of CD98hc by monoclonal antibody is effective in the treatment of acute cardiac allograft rejection, which may be useful clinically in the future.展开更多
Hepatocellular carcinoma (HCC), chronic hepatitis B (CHB) and chronic hepatitis C (CHC) are characterized by exhaustion of the specific CD8<sup>+</sup> T cell response. This process involves enhancement of...Hepatocellular carcinoma (HCC), chronic hepatitis B (CHB) and chronic hepatitis C (CHC) are characterized by exhaustion of the specific CD8<sup>+</sup> T cell response. This process involves enhancement of negative co-stimulatory molecules, such as programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen-4 (CTLA-4), 2B4, Tim-3, CD160 and LAG-3, which is linked to intrahepatic overexpression of some of the cognate ligands, such as PD-L1, on antigen presenting cells and thereby favouring a tolerogenic environment. Therapies that disrupt these negative signalling mechanisms represent promising therapeutic tools with the potential to restore reactivity of the specific CD8<sup>+</sup> T cell response. In this review we discuss the impressive in vitro and in vivo results that have been recently achieved in HCC, CHB and CHC by blocking these negative receptors with monoclonal antibodies against these immune checkpoint modulators. The article mainly focuses on the role of CTLA-4 and PD-1 blocking monoclonal antibodies, the first ones to have reached clinical practice. The humanized monoclonal antibodies against CTLA-4 (tremelimumab and ipilimumab) and PD-1 (nivolumab and pembrolizumab) have yielded good results in testing of HCC and chronic viral hepatitis patients. Trelimumab, in particular, has shown a significant increase in the time to progression in HCC, while nivolumab has shown a remarkable effect on hepatitis C viral load reduction. The research on the role of ipilimumab, nivolumab and pembrolizumab on HCC is currently underway.展开更多
Objective To investigate the effects of estrogen(E_2)level on regulatory T cells(Treg)in peripheral blood during pregnancy.Methods:A total of 30 healthy non-pregnant women were selected as control group,90 pregnant wo...Objective To investigate the effects of estrogen(E_2)level on regulatory T cells(Treg)in peripheral blood during pregnancy.Methods:A total of 30 healthy non-pregnant women were selected as control group,90 pregnant women of early,middle and late pregnancy and 30 postpartum women at 1 month after parturition were selected as experimental groups including early pregnancy group,middle pregnancy group and late pregnancy group;the proportions of CD4^+CD25^+Treg and CD4^+CD25^+CD127^-Treg among CD4 T cells were detected by flow cytometry;the serum estrogen content in peripheral blood was detected by electrochemical immune luminescence method.Results:E_2 level was coincident with the change of Tregs number during pregnancy.The estrogen content in peripheral blood increased gradually from early pregnancy to late pregnancy,then decreased significantly after parturition,and the level at 1 month after parturition down to the level in non-pregnancy group(P>0.05);the level of E_2 in pregnancy groups were significantly higher than those in non-pregnancy group(P<0.01);and there were significant differences among early pregnancy group,middle pregnancy group and late pregnancy group(P<0.05).The proportions of CD4^+CD25^+Treg and CD4^+CD25^+CD127^-Treg in pregnancy groups were significantly higher than those in non-pregnancy group(P<0.05),but decreased significantly after parturition,and there was no significant difference between non-pregnancy group and postpartum women group(P>0.05):the proportions in middle and late pregnancy groups were significantly higher than those in early pregnancy group(P<0.05).but decreased slightly in late pregnancy group,there was no significant difference between late pregnancy group and middle pregnancy group(P>0.05).There was correlation between Tregs number with estrogen level during pregnancy.The proportion of CD4^+CD25^+Treg and CD4^+CD25^+CD 127^-Treg were positively correlated with estrogen level.Conclusions:High proportion of CD4^+CD25^+Trcg and CD4^+CD25^+CD127^-Treg is closely related to the high level of E,during pregnancy.It suggested that high level of estrogen may induce an increase of CD4^+CD25^+Treg in peripheral blood.and then influence the immune function of pregnant women.The results of this experiment might play an important role of estrogen in immune-modulation during pregnancy.展开更多
The observation of efficient blue, green, orange and red luminescence from CdS nanocrystals made by using a reverse micelle method was reported. The blue luminescence about 480 nm is attributed to the radiative recomb...The observation of efficient blue, green, orange and red luminescence from CdS nanocrystals made by using a reverse micelle method was reported. The blue luminescence about 480 nm is attributed to the radiative recombination of electron-hole pairs. The red luminescence around 650 nm is due to the radiative recombination of the exciton trapped in the nanocrystal surface defect states. The combination of different portion of band-edge emission and surface trap state emission results in green and orange luminescence for the nanocrystals. The CdS nanocrystals with efficient multicolored luminescence may find potential application in full color displays and biolabelings.展开更多
文摘CD98 heavy chain（CD98hc）,encoded by Slc3a2,is a widely expressed vertebrate membrane protein whose functions are known as facilitating amino acid transporter and mediating integrin signaling.Little is known about its function on T lymphocyte mediated immune response to alloantigen. Here we report that we successfully deleted CD98hc in T cells by crossing mice bearing a loxP-flanked Slc3a2 allele with those expressing Cre re-combinase in T cells（CD4-Cre+）.T cell-specific deficient of CD98hc resulted in lower responses to alloantigen stimulation in mixed lymphocyte reaction assay.Heterotopic cardiac grafting was then performed from BALB/c（H-2K<sup>d</sup>） to CD98hc<sup>lox/-</sup>CD4-Cre<sup>+</sup> /C57BL/6（H-2K<sup>b</sup>） or control littermate C57BL/6 （B6） mice.We found that all CD98hc<sup>lox/</sup>-CD4-Cre<sup>+</sup> recipients had indefinite survival（MST:】100days, n=8）.In contrast,all littermate B6 recipients suffered acute rejection[MST:（7.4±0.5）d,n=12].In addition,the survival of the skin grafts from donor BALB/c mice to more than postoperative day （POD） 100 heart-bearing tolerant CD98hc<sup>lox/-</sup>CD4- Cre<sup>+</sup> recipients was significantly prolonged[MST: （15.2±2.2）d,n =5]compared that of the B6 mice [MST:（8.2±1.3）d,n=9].In consistent with graft survival, we found that the graft infiltration cells on POD7 were fewer than that of the B6 mice by FACS and immune-staining analysis.Also chemotaxis assay data revealed that the migrated CD98hc<sup>lox/-</sup>CD4-Cre<sup>+</sup> lymphocyte were less than that of B6 in the presence of different concentration of chemokines CCL2, CCL5,and CCL2 plus CCL5.In addition,a neutralizing antibody（clone 26-24）specific against CD98hc prolonged the graft survival[MST:（13.4±2.7）d,n=8; P=0.001]in the B6 recipients after they received the BALB/c mice heart.Hence our data indicated that T cell-specific deficient of CD98hc impaired proliferate in response to alloantigens and decreased migration ability result in inducing immune tolerance after cardiac transplantation.Moreover,the application of the blocked of CD98hc by monoclonal antibody is effective in the treatment of acute cardiac allograft rejection, which may be useful clinically in the future.
基金Supported by "Instituto de Salud Carlos Ⅲ",Spain& "European Regional Development Fund(ERDF)a way of making Europe",No.PI12/00130 and No.PI15/00074and"Gilead Spain&Instituto de Salud Carlos Ⅲ",No.GLD14_00217
文摘Hepatocellular carcinoma (HCC), chronic hepatitis B (CHB) and chronic hepatitis C (CHC) are characterized by exhaustion of the specific CD8<sup>+</sup> T cell response. This process involves enhancement of negative co-stimulatory molecules, such as programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen-4 (CTLA-4), 2B4, Tim-3, CD160 and LAG-3, which is linked to intrahepatic overexpression of some of the cognate ligands, such as PD-L1, on antigen presenting cells and thereby favouring a tolerogenic environment. Therapies that disrupt these negative signalling mechanisms represent promising therapeutic tools with the potential to restore reactivity of the specific CD8<sup>+</sup> T cell response. In this review we discuss the impressive in vitro and in vivo results that have been recently achieved in HCC, CHB and CHC by blocking these negative receptors with monoclonal antibodies against these immune checkpoint modulators. The article mainly focuses on the role of CTLA-4 and PD-1 blocking monoclonal antibodies, the first ones to have reached clinical practice. The humanized monoclonal antibodies against CTLA-4 (tremelimumab and ipilimumab) and PD-1 (nivolumab and pembrolizumab) have yielded good results in testing of HCC and chronic viral hepatitis patients. Trelimumab, in particular, has shown a significant increase in the time to progression in HCC, while nivolumab has shown a remarkable effect on hepatitis C viral load reduction. The research on the role of ipilimumab, nivolumab and pembrolizumab on HCC is currently underway.
基金supported by Science and Technology Project of Jiangxi Province(2009BSB10909)
文摘Objective To investigate the effects of estrogen(E_2)level on regulatory T cells(Treg)in peripheral blood during pregnancy.Methods:A total of 30 healthy non-pregnant women were selected as control group,90 pregnant women of early,middle and late pregnancy and 30 postpartum women at 1 month after parturition were selected as experimental groups including early pregnancy group,middle pregnancy group and late pregnancy group;the proportions of CD4^+CD25^+Treg and CD4^+CD25^+CD127^-Treg among CD4 T cells were detected by flow cytometry;the serum estrogen content in peripheral blood was detected by electrochemical immune luminescence method.Results:E_2 level was coincident with the change of Tregs number during pregnancy.The estrogen content in peripheral blood increased gradually from early pregnancy to late pregnancy,then decreased significantly after parturition,and the level at 1 month after parturition down to the level in non-pregnancy group(P>0.05);the level of E_2 in pregnancy groups were significantly higher than those in non-pregnancy group(P<0.01);and there were significant differences among early pregnancy group,middle pregnancy group and late pregnancy group(P<0.05).The proportions of CD4^+CD25^+Treg and CD4^+CD25^+CD127^-Treg in pregnancy groups were significantly higher than those in non-pregnancy group(P<0.05),but decreased significantly after parturition,and there was no significant difference between non-pregnancy group and postpartum women group(P>0.05):the proportions in middle and late pregnancy groups were significantly higher than those in early pregnancy group(P<0.05).but decreased slightly in late pregnancy group,there was no significant difference between late pregnancy group and middle pregnancy group(P>0.05).There was correlation between Tregs number with estrogen level during pregnancy.The proportion of CD4^+CD25^+Treg and CD4^+CD25^+CD 127^-Treg were positively correlated with estrogen level.Conclusions:High proportion of CD4^+CD25^+Trcg and CD4^+CD25^+CD127^-Treg is closely related to the high level of E,during pregnancy.It suggested that high level of estrogen may induce an increase of CD4^+CD25^+Treg in peripheral blood.and then influence the immune function of pregnant women.The results of this experiment might play an important role of estrogen in immune-modulation during pregnancy.
基金Projects(20601012 20601016) supported by the National Natural Science Foundation of ChinaProjects(206077, 206043, 10013-121008) supported by Inner Mongolia University, China
文摘The observation of efficient blue, green, orange and red luminescence from CdS nanocrystals made by using a reverse micelle method was reported. The blue luminescence about 480 nm is attributed to the radiative recombination of electron-hole pairs. The red luminescence around 650 nm is due to the radiative recombination of the exciton trapped in the nanocrystal surface defect states. The combination of different portion of band-edge emission and surface trap state emission results in green and orange luminescence for the nanocrystals. The CdS nanocrystals with efficient multicolored luminescence may find potential application in full color displays and biolabelings.
