Expression of chemokine receptors CCR3, CCR5 and CXCR3 on CD4^＋ T cells in CBA/J×DBA/2 mouse model, selectively induced by IL-4 and IL-10, regulates the embryo resorption rate

Background Chemokines and their receptors have been a research focus in transplantation immunology. Chemokines and their receptors play a role in lymphocyte recruitment and differentiation process. This study aimed to observe whether IL-4 and IL-10 may regulate the expression of chemokine receptors CCR3, CCR5 and CXCR3 on CD4^＋ T cells in CBA/J×DBA/2 mouse model and to explore the role of CCR3, CCR5, CXCR3 in immune tolerance in pregnancy. Methods The mouse model of spontaneous abortion （CBA/J×DBA/2） and the normal pregnant mouse model （CBA/J×BALB/c） were used. CBA/J×DBA/2 mice were injected with IL-4 （CBA/J×DBA/2-IL-4）, IL-4 and IL-10 （CBA/J×DBA/2-IL-4＋IL-10）, or normal saline （CBA/J×DBA/2-NS） as a control. The expression of CCR3, CCR5 and CXCR3 on CD4^＋ T cells from mouse peripheral blood was measured by the double-labelled FCM method, and the embryo resorption rate was also examined. Results The embryo resorption rate in the CBA/J×DBA/2 group without any treatment was significantly higher than that in the CBA/J×BALB/c group （17.9% vs 3.7%, P 〈0.01）. The embryo resorption rate in the CBA/J×DBA/2 group immunized with IL-4 or IL-4 together with IL-10 was significantly decreased, compared with that in the control and NS groups respectively. CCR3 expression on CD4^＋ T cells in the CBA/J×DBA/2 group without any treatment was significantly lower than that in the CBA/J×BALB/c group （0.3738±0.3575 vs 1.2190±0.2772, P 〈0.01）; both CCR5 （3.0900±1.5603 vs 1.2390±0.6361, P〈0.01） and CXCR3 （2.4715±0.9074 vs 0.9200±0.5585, P 〈0.01） expressions on CD4^＋ T cells of the CBA/J×DBA/2 group without any treatment were significantly higher than those of the CBA/J×BALB/c group. Significant up-regulation of CCR3 and down-regulation of CXCR3 were found in the CBA/J×DBA/2 group treated with IL-4 （CCR3： 2.0360±0.6944, CXCR3： 1.3510±0.5263, P〈0.01） or IL-4 and IL-10 （CCR3： 1.8160±1.0947, CXCR3：1.0940±0.7168, P〈0.01）. Because of the CCR5, IL-4 and IL-10 （1.9400±0.8504 vs 3.0900±1.5603, P 〈0.05）, but IL-4 alone （2.5310±1.3595 vs 3.0900±1.5603, P 〉0.05） treatment significantly decreased the expression of CCR5 in CBA/J×DBA/2. Conclusions The abnormal expression of CCR3, CCR5 and CXCR3 on CD4^＋ T cells may play an important role in the pathogenesis of spontaneous abortion. The pregnancy immune tolerance may be induced through selective induction of CCR3, CCR5 and CXCR3 expressions by IL-4 together with IL-10.

Relationship between expression of chemokine receptors CCR3, CCR5 and CXCR3 on CD4^＋ T cells and spontaneous abortion in mice

Background Previous studies have shown that local immune cells in the feto-maternal interface are recruited from peripheral blood, and that chemokines and their receptors play an initial and key role in this recruitment process. In this study, we aimed to determine whether spontaneous abortion is associated with the expression of chemokine receptors CCR3, CCR5, and CXCR3 on CD4^＋ T cells. Methods Peripheral blood, spleen, and thymus were collected from the spontaneous abortion mouse model CBA/JxDBA/2 （SA group, n=14）, the normal pregnant mouse model CBA/JxBALB/c （NP group, n=13）, and normal non-pregnant CBA/J mice （NNP group, n=11）. The number of chemokine receptors CCR3, CCR5, and CXCR3 expressed on CD4^＋ T cells was measured by double-label flow cytometry （FCM） method. Results In peripheral blood, the SA group had significantly lower CCR3 expression （P 〈0.01） and higher CCR5 and CXCR3 expression （P 〈0.01） on CD4^＋ T cells than did the NP group. But comparing these chemokines between the SA and NNP groups, there was no significant difference （P 〉0.05）. In spleen, the SA group expressed significantly lower CCR3 expression （P 〈0.01） and higher CCR5 and CXCR3 expression （P 〈0.05） on CD4^＋ T cells than did the NP group. When compared with the NNP group, the SA group had significantly higher CCR3 expression （P 〈0.01）, but was not statistically different with regards to the other two chemokines （P 〉0.05）. In thymus, the SA group had significantly lower CCR3 expression （P 〈0.05） and higher CXCR3 expression （P 〈0.05） on CD4^＋ T cells than the NP group, with no significant difference in CCR5 expression （P 〉0.05）. Compared with the NNP group, the SA group had higher CCR3 expression （P 〈0.01）, but there was no statistical difference in CXCR3 and CCR5 expression （P 〉0.05） between the two groups. Conclusion The abnormal expression of CCR3, CCR5 and CXCR3 on CD4^＋ T cells may play an important role in the pathogenesis of spontaneous abortion.

Biological features of intrahepatic CD4^(+)CD25^(+)T cells in the naturally tolerance of rat liver transplantation

The biological features of intrahepatic CD4^(+)CD25^(+)T regulatory cells in the naturally tolerance of rat liver transplantation were explored.Orthotopic liver transplan-tation was performed in two allogeneic rat strain combina-tions,one with fatal immunosuppression despite a complete major histocompatibility complex mismatch.The subjects were divided into three groups according to different donors and recipients[Tolerance group:LEW-to-DA;Rejection group:DA-to-LEW;Syngegnic group(control group):DA-to-DA].The proportion of intrahepatic CD4^(+)CD25^(+)T cells from three groups was determined by flow cytometry(FCM)in different time.The intrahepaitc CD4^(+)CD25^(+)T cells were isolated by magnetic activated cell sorting(MACS)method and identified by FCM.The Foxp3 mRNA was detected by reverse transcriptase polymerase chain reaction(RT-PCR).And their suppression on the proliferation of CD4^(+)CD25^(-)T effector cells was analyzed by cell proliferation assay in vitro.Beginning immediately after transplantation,the proportion of Treg cells increased over time in both allogeneic groups but was significantly greater in the Rejection group.The pro-portion of Treg cells declined after day 5,and such reduction was more dramatic in the Rejection group than in the Tole-rance group.Animals in the Tolerance group showed a second increase in the proportion after day 14.Intrahepatic CD4^(+)CD25^(+)T cells isolated from spontaneous tolerance models inhibited the proliferation of mixed lymphocyte reaction.The purity of CD4^(+)CD25^(+)Tcells sorted by MACS was 86%–93%.The CD4^(+)CD25^(+)T cells could specifically express the Foxp3 gene compared with CD4^(+)CD25^(-)T cells.In vitro,the spleen cells from LEW rats can irritate the proliferation of CD4^(+)CD25^(+)T cells more obviously than the syngegnic spleen cells.CD4^(+)CD25^(+)Tr cells could suppress the proliferation of CD4^(+)CD25^(-)T cells,but the inhibition was reversed by exo-genous IL-2(200 U/mL).The CD4^(+)CD25^(+)T regulatory cells specifically express the Foxp3 gene,which may play animpor-tant role in the induction of liver transplantation tolerance by suppressing the reaction of effective T cells.

SATURATION EFFECTS FOR CTL MEDIATED CONTROL OF HIV-1 INFECTION： A MATHEMATICAL STUDY

The relations between the Human Immunodeficiency Virus-1 （HIV-1） and the human immune system are astonishingly multifaceted, where the critical role for cytotoxic T lymphocytes （CTLs） in the suppression of viral replication in HIV-1 infected individuals cannot be ignored. In this research paper, we have proposed a mathematical model incorporating half saturation constant through the CTL mediated killing process and also in that sense, it has been infiltrated in the generation process of CTL through infected cells. To make the model more realistic, a time lag is introduced in the generation term of CTL population. Also an optimal control theory paradigm is used in our mathematical model to suppress the viral production. From our entire analysis, we have found threshold condition of half saturation constant and treatment schedule so that we can handle the situation of Acquired Immunodeficiency Syndrome （AIDS） patients in a better way. Our analysis reveals that, if the half saturation constant is around 47 mm^-3 in the saturation process and the drug therapy is to be used around 76 days, then we can get adequate results for better treatment of a HIV-1 patient. Based on numerical results, we observed that in a highly unstable situation, administration of chemotherapy at a high dose can stabilize the system.

Dectin-2与真菌感染免疫

Dectin-2是21世纪新发现的模式识别受体（pattern recognition receptor,PRR）,属于C型凝集素受体家族,其胞外C端有凝集素样糖识别域（carbohydrate recognition domain,CRD）,可通过识别病原体细胞壁的高甘露糖结构域,诱发下游信号传导,启动基因表达,激活固有免疫,并促进抗真菌的获得性免疫如CD4^＋T细胞向Th17细胞的分化。