Publications (8)14.76 Total impact
-
Article: Xenoreactive CD4+ memory T cells resist inhibition by anti-CD44 mAb and reject islet grafts via a Th2-dependent pathway.
[show abstract] [hide abstract]
ABSTRACT: Memory T cells are a significant barrier to the induction of transplant tolerance. Our previous study demonstrated that multiple applications of anti-CD44 monoclonal antibody (mAb) could significantly inhibit CD4(+) memory T cells from mediating rejection of cardiac allografts. Now, we sought to explore the effect and mechanism of anti-CD44 mAb on the rejection of islet allografts and xenografts mediated by CD4(+) memory T cells. In this study, we first engrafted skin grafts of C57BL/6 (B6) mice or Dark Agouti (DA) rats onto BALB/c mice to induce donor-reactive memory T cells. We adoptively transferred purified CD4(+) memory T cells to BALB/c origin nude mice and then transplanted islet allografts and xenografts to produce the Allo-Tx and Xeno-Tx models, respectively. We subsequently administered multiple anti-CD44 mAb and observed changes in the survival times of the islet grafts. In the Allo-Tx model, the mean survival time (MST) of the grafts was 7.7 days in the isotype group, and 20.3 days in the anti-CD44 group. In the Xeno-Tx model, the MST of the grafts was 7.2 days in the isotype group and 8.2 days in the anti-CD44 group. Compared with the isotype group, CD4(+) T cells on the grafts in the anti-CD44 group were significantly decreased in both the Allo-Tx and Xeno-Tx models, but the proportion of CD4(+) memory T cells in the spleens and draining lymph nodes of the recipient nude mice in the anti-CD44 group was significantly decreased in the Allo-Tx model, while it was increased in the Xeno-Tx model. The production of donor-specific IgG antibody in the anti-CD44 group did not vary in the Allo-Tx model, while it was markedly elevated in the Xeno-Tx model. Furthermore, the expression of interferon gamma in the anti-CD44 group was markedly decreased in both the Allo-Tx and Xeno-Tx models, while the expression of IL-4 in the anti-CD44 group was significantly increased only in the Xeno-Tx model. Multiple applications of the anti-CD44 mAb could significantly inhibit donor-reactive CD4(+) memory T cells from rejecting grafts via a Th1-dependent pathway, but xenoreactive CD4(+) memory T cells can avoid the effects of anti-CD44 mAb to reject islet xenografts via a Th2-dependent pathway.Xenotransplantation 07/2011; 18(4):252-61. · 2.33 Impact Factor -
Article: CD44/CD70 blockade and anti-CD154/LFA-1 treatment synergistically suppress accelerated rejection and prolong cardiac allograft survival in mice.
[show abstract] [hide abstract]
ABSTRACT: Current treatments that are efficient in controlling effector T cell responses to allografts have limited efficacy on the accelerated rejection mediated by memory T cells. Effective targeting of alloreactive memory T cells may therefore be explored to improve therapeutic approaches towards solving this problem. In this study, we investigated the synergistic effect of CD44/CD70 blockade and anti-CD154/LFA-1 treatment on the accelerated rejection mediated by memory T cells. While CD44/CD70 blockade had limited effects on the alloresponses of effector T cells in vivo, it diminished the expansion of both CD4(+) and CD8(+) memory T cells in recipients adoptively transferred with donor-sensitized T cells. In combination with anti-CD154/LFA-1 treatment, CD44/CD70 blockade significantly prolonged cardiac allograft survival in adoptive transfer recipients. We demonstrated that treatment with the combination of all four antibodies (anti-CD154/LFA-1/CD44/CD70) inhibited accelerated rejection by markedly suppressing the alloresponses of effector and memory T cells and reducing the number of graft-infiltration lymphocytes in adoptive transfer recipients. Meanwhile, CD44/CD70 blockade and anti-CD154/LFA-1 treatment synergically enhanced regulatory T cells (Tregs) by increasing the proportion of splenic Tregs and the expression of IL-10 in these recipients. Our findings contribute to the potential design of therapies for accelerated allograft rejection.Scandinavian Journal of Immunology 06/2011; 74(5):430-7. · 2.23 Impact Factor -
Article: Combination of monoclonal antibodies with DST inhibits accelerated rejection mediated by memory T cells to induce long-lived heart allograft acceptance in mice.
[show abstract] [hide abstract]
ABSTRACT: Donor-reactive memory T cells mediated accelerated rejection is known as a barrier to the survival of transplanted organs. We investigated the combination of different monoclonal antibodies (mAbs) and donor-specific transfusion (DST) in memory T cells-based adoptive mice model. In the presence of donor-reactive memory T cells, the mean survival time (MST) of grafts in the anti-CD40L/LFA-1/DST group was 49.8d. Adding anti-CD44/CD70 mAbs to anti-CD40L/LFA-1/DST treatment. The MST was more than 100 d (MST>100 d). Compared with anti-CD40L/LFA-1/DST group, anti-CD40L/LFA-1/CD44/CD70/DST group notably reduced the expansion of memory T cells, enhanced the proportion of CD4+Foxp3+ regulatory T cells (Tregs) and suppressed donor-specific responses. Our data suggest that anti-CD40L/LFA-1/CD44/CD70mAbs and DST can synergistically inhibit accelerated rejection mediated by memory T cells to induce long-lived heart allograft acceptance in mice.Immunology letters 04/2011; 138(2):122-8. · 2.91 Impact Factor -
Article: Blockade of CD27/CD70 pathway to reduce the generation of memory T cells and markedly prolong the survival of heart allografts in presensitized mice.
[show abstract] [hide abstract]
ABSTRACT: Alloreactive memory T cells are a major obstacle to transplantation acceptance due to their capacity for accelerated rejection. C57BL/6 mice that had rejected BALB/c skin grafts 4 weeks earlier were used as recipients. The recipient mice were treated with anti-CD154/LFA-1 with or without anti-CD70 during the primary skin transplantation and anti-CD154/LFA-1 or not during the secondary transplantation of BALB/c heart. We evaluated the impact of combinations of antibody-mediated blockade on the generation of memory T cells and graft survival after fully MHC-mismatched transplantations. One month after the primary skin transplantation, the proportions of CD4(+) memory T cells/CD4(+) T cells and CD8(+)memory T cells/CD8(+) T cells in the anti-CD154/LFA-1 combination group were 47.32±4.28% and 23.18±2.77%, respectively. In the group that included anti-CD70 treatment, the proportions were reduced to 34.10±2.71% and 12.19±3.52% (P<0.05 when comparing the proportion of memory T cells between the two groups). The addition of anti-CD70 to the treatment regimen prolonged the mean survival time following secondary heart transplantation from 10days to more than 90days (P<0.001). Furthermore, allogenic proliferation of recipient splenic T cells and graft-infiltrating lymphocytes were significantly decreased. Meanwhile, the proportion of regulatory T cells was increased to 9.46±1.48% on day 100 post-transplantation (P<0.05). The addition of anti-CD70 to the anti-CD154/LFA-1 combination given during the primary transplantation reduced the generation of memory T cells. This therapy regimen provided a potential means to alleviate the accelerated rejection mediated by memory T cells during secondary heart transplantation and markedly prolong the survival of heart allografts.Transplant Immunology 03/2011; 24(4):195-202. · 1.46 Impact Factor -
Article: Arsenic trioxide combined with co-stimulatory molecule blockade prolongs survival of cardiac allografts in alloantigen-primed mice.
[show abstract] [hide abstract]
ABSTRACT: Various memory cell populations existing before organ transplantation are believed to be important barriers to extending the graft survival time. Here, we report that arsenic trioxide (As(2)O(3)), a common component of some Chinese traditional preparations, could obviously reduce the proliferation of splenic T cells in alloantigen-primed mice in vitro. Furthermore, we evaluated As(2)O(3) treatment alone or in combination with blocking monoclonal antibodies (mAb) against co-stimulatory molecules (LFA-1 and CD154) in the prevention of heart transplant rejection in alloantigen-primed mice. Alloantigen-primed mice were randomly divided into 4 groups of 6 animals each. The control group was given normal saline; the As(2)O(3) group received As(2)O(3) (5 mg/kg/d) (i.p.) on days 0-10 post-transplantation; the Ab group received 100 μg anti-LFA-1 mAb+250 μg anti-CD154 mAb (i.p.) on the day of transplantation and 3 more times every alternate day and the As(2)O(3)+Ab group received a combined As(2)O(3) and Ab treatment protocol. The survival of the allografts was almost doubled among the As(2)O(3) group and Ab group compared with the control group (5, 5.6 vs 3.3 days). A marked prolongation (16 days) of graft survival was achieved by the combination protocol compared with the control group (3.3 days; P<0.05). None of the treatment group showed side effects. Five days after transplantation, cardiac allografts, splenic T cells and serum were harvested for analysis. Compared with the control group, most of the treatment groups showed: (i) alleviation of allograft rejection in different levels; (ii) IFN-γ expression was reduced and TGF-β expression increased in both peripheral blood and within the grafts; (iii) the proportions of CD4(+) or CD8(+) memory T cells in the spleen of the recipients were significantly reduced while the expression of regulatory T cells (Tregs) was enhanced; (iv) the alloresponses of memory T cells were inhibited, and levels of alloantibodies in recipients' sera were also decreased. Among all these changes, the As(2)O(3)+Ab group showed the most significant changes. Our study highlights an obvious synergistic action of As(2)O(3) when combined with co-stimulatory molecules blockade in prolonging the survival of cardiac allografts in alloantigen-primed mice.Transplant Immunology 10/2010; 24(1):57-63. · 1.46 Impact Factor -
Article: Isatis tinctoria L. combined with co-stimulatory molecules blockade prolongs survival of cardiac allografts in alloantigen-primed mice.
[show abstract] [hide abstract]
ABSTRACT: Memory T cells present a unique challenge in transplantation. Although memory T cells express robust immune responses to invading pathogens, they may be resistant to the effects of immunosuppressive therapies used to prolong graft survival. In previous studies, we found that compound K, the synthesized analogue of highly unsaturated fatty acids from Isatis tinctoria L., reduced acute cardiac allograft rejection in mice (Wang et al., 2009 [1]). Here, we further investigated the effect of compound K on cardiac allograft rejection in alloantigen-primed mice. We found that compound K significantly inhibited CD4(+) and CD8(+) memory T cells proliferation in a mixed lymphocyte reaction (MLR). In vivo, compound K combined with anti-CD154 and anti-LFA-1 monoclonal antibodies (mAbs) significantly extended the survival time of heart grafts in alloantigen-primed mice with no obvious toxic side effects. Furthermore, our data suggests that compound K works by reducing the expression of both IL-2 and IFN-gamma within the graft rather than enhancing expression of regulatory T cells (Tregs). Compound K can also inhibit the alloresponses of memory T cells, while increasing the proportion of CD4(+) memory T cells in the spleen of the recipients and significantly reducing the level of alloantibodies in the serum. Our study highlights the unique immune effects of compound K that may be further explored for clinical use in extending the survival of transplant grafts.Transplant Immunology 03/2010; 23(1-2):34-9. · 1.46 Impact Factor -
Article: Anti-CD44 monoclonal antibody inhibits heart transplant rejection mediated by alloantigen-primed CD4(+) memory T cells in nude mice.
[show abstract] [hide abstract]
ABSTRACT: Donor-reactive CD4(+)memory T cells threaten the survival of transplanted organs. In this study, we used anti-CD44 monoclonal antibody (mAb) to inhibit adoptively transferred B6-reactive CD4(+)memory T cells (BALB/c origin) and to induce tolerance of B6 hearts in nude mice. The median survival time (MST) of the grafts was 6 days in the isotype group, and more than 100 days in the group treated with 8 doses of anti-CD44 at four-day intervals. Histological analysis revealed that the mean rejection level was Grade 3 in the isotype group, and Grade 0 or 1 in the multi-dose anti-CD44 treatment group. Compared with the isotype group, the multiply treated anti-CD44 group had significantly decreased IL-2 and IFN-γ expressions, while IL-10 and TGF-β were increased in the serum and the graft. Foxp3 in the graft was also increased. These data demonstrate that alloreactive CD4(+) memory T cells mediate the destruction of allografts, and the adhesion molecule CD44 plays an important role in this course. Anti-CD44 mAb may promote the reduction of CD4(+)memory T cells and the production of regulatory T cells (Tregs). Furthermore, Tregs are maintained at a certain level while suppressing cellular immunity and inducing the grafts long-term survival in transplant recipients.Immunological Investigations 01/2010; 39(8):807-19. · 1.47 Impact Factor -
Article: Synergistic effects of Isatis tinctoria L. and tacrolimus in the prevention of acute heart rejection in mice.
[show abstract] [hide abstract]
ABSTRACT: Although immunosuppressive treatments are available for acute cardiac rejection no viable treatment exists for long-term cardiac graft failure. Moreover, the extended use of calcineurin inhibitor immunosuppressants, the mainstay of current treatment for cardiac transplantation, leads to significant side effects such as nephrotoxicity and an increased risk of cardiac disease. Because some agents used in Traditional Chinese Medicine (TCM) have strong immunosuppressive effects coupled with low toxicity, we investigated the effect of Compound K (K), the synthesized analogue of highly unsaturated fatty acids from Isatis tinctoria L., either as a single treatment or combined with tacrolimus (FK-506) on acute cardiac allograft rejection. We compared the ability of K alone, or in combination with FK-506, to inhibit acute heart transplant rejection both in vitro and in vivo. We found that the inhibition of lymphocyte proliferation was positively correlated with K concentration. K significantly reduced IL-2 and IFN-gamma expression levels and significantly inhibited lymphocyte proliferation in both a lymphocyte transformation test and a mixed lymphocyte reaction (MLR). We also found that the inhibitory effect of a combination of K and a sub-therapeutic dose of FK-506 (SubFK-506) was stronger than that of full-dose FK-506 alone. Oral administration of K reduced acute cardiac allograft rejection in mice and had no apparent toxicity. In vivo, the immunosuppressive effect of K combined with a half-dose of FK-506 was equivalent to that of a full-dose of FK-506 alone. K combined with a half-dose of FK-506 reduced the expression levels of IL-2 and IFN-gamma (both within the graft and in the recipients' serum) more effectively than a full-dose of FK-506. These results show that K has significant immunosuppressive effects both in vitro and in vivo. When used as a combination therapy with FK-506 we see a powerful inhibition of rejection with no obvious toxic side effects. The mechanism of action is postulated to involve the inhibition of IL-2 and IFN-gamma expressions by lymphocytes, rather than the activation of Tr1 cells via the production of IL-10.Transplant Immunology 09/2009; 22(1-2):5-11. · 1.46 Impact Factor
Top Journals
Institutions
-
2009–2011
-
Xiamen University
- • School of Life Sciences
- • Organ transplantation institute
Xiamen, Fujian, China
-