The role of the vascularized bone marrow component as a continuous source of donor-derived hematopoietic stem cells that facilitate tolerance induction of vascularized composite allografts is not completely understood...The role of the vascularized bone marrow component as a continuous source of donor-derived hematopoietic stem cells that facilitate tolerance induction of vascularized composite allografts is not completely understood.In this study,vascularized composite tissue allograft transplantation outcomes between recipients receiving either conventional bone marrow transplantation(CBMT)or vascularized bone marrow(VBM)transplantation from Balb/c(H2d)to C57BL/6(H2b)mice were compared.Either high-or low-dose CBMT(1.5×10^(8)or 3×10^(7)bone marrow cells,respectively)was applied.In addition,recipients were treated with costimulation blockade(1 mg anti-CD154 and 0.5 mg CTLA4Ig on postoperative days 0 and 2,respectively)and short-term rapamycin(3 mg/kg/day for the first posttransplant week and then every other day for another 3 weeks).Similar to high-dose conventional bone marrow transplantation,5/6 animals in the vascularized bone marrow group demonstrated long-term allograft survival(>120 days).In contrast,significantly shorter median survival was noted in the low-dose CBMT group(~64 days).Consistently high chimerism levels were observed in the VBM transplantation group.Notably,low levels of circulating CD4^(+)and CD8^(+)T cells and a higher ratio of Treg to Teff cells were maintained in VBM transplantation and high-dose CBMT recipients(>30 days)but not in low-dose VBM transplant recipients.Donor-specific hyporesponsiveness was shown in tolerant recipients in vitro.Removal of the vascularized bone marrow component after secondary donor-specific skin transplantation did not affect either primary allograft or secondary skin graft survival.展开更多
BACKGROUND Heart transplantation is a crucial intervention for severe heart failure,yet the challenge of organ rejection is significant.Bone marrow mesenchymal stem cells(BMSCs)and their exosomes have demonstrated pot...BACKGROUND Heart transplantation is a crucial intervention for severe heart failure,yet the challenge of organ rejection is significant.Bone marrow mesenchymal stem cells(BMSCs)and their exosomes have demonstrated potential in modulating T cells,dendtitic cells(DCs),and cytokines to achieve immunomodulatory effects.DCs,as key antigen-presenting cells,play a critical role in shaping immune responses by influencing T-cell activation and cytokine production.Through this modulation,BMSCs and their exosomes enhance graft tolerance and prolonging survival.AIM To explore the immunomodulatory effects of exosomes derived from BMSCs overexpressing microRNA-540-3p(miR-540-3p)on cardiac allograft tolerance,focusing on how these exosomes modulating DCs and T cells activity through the CD74/nuclear factor-kappaB(NF-κB)pathway.METHODS Rat models were used to assess the impact of miR-540-3p-enhanced exosomes on immune tolerance in cardiac allografts.MiR-540-3p expression was manipulated in BMSCs,and derived exosomes were collected and administered to the rat models post-heart transplantation.The study monitored expression levels of major histocompatibility complex II,CD80,CD86,and CD274 in DCs,and quantified CD4^(+)and CD8^(+)T cells,T regulatory cells,and cytokine profiles.RESULTS Exosomes from miR-540-3p-overexpressing BMSCs lead to reduced expression of immune activation markers CD74 and NF-κB p65 in DCs and T cells.Rats treated with these exosomes showed decreased inflammation and improved cardiac function,indicated by lower levels of pro-inflammatory cytokines(interleukin-1β,interferon-γ)and higher levels of anti-inflammatory cytokines(interleukin-10,transforming growth factorβ1).Additionally,miR-540-3p skewed the profiles of DCs and T cells towards immune tolerance,increasing the ratio of T regulatory cells and shifting cytokine secretion to favor graft acceptance.CONCLUSION Exosomes derived from BMSCs overexpressing miR-540-3p significantly enhance immune tolerance and prolong cardiac allograft survival by modulating the CD74/NF-κB pathway,which regulates activities of DCs and T cells.These findings highlight a promising therapeutic strategy to improve heart transplantation outcomes and potentially reduce the need for prolonged immunosuppression.展开更多
Objective: A murine model of mixing syngeneic and haploidentical major histocompatibility complex (MHC) matched bone marrow cells transplant was used to evaluate the effect of splenocytes in graft-versus-host disease ...Objective: A murine model of mixing syngeneic and haploidentical major histocompatibility complex (MHC) matched bone marrow cells transplant was used to evaluate the effect of splenocytes in graft-versus-host disease (GVHD) and host-versus-graft reaction (HVGR). Methods: BALB/C recipient mice were lethally conditioned with 8.5 Gy and injected with different grafts which consisted of syngeneic bone marrow cells plus splenocytes (SPLCs) and haploidentical MHC matched bone marrow cells (BMCs)plus different doses of splenocytes. Recipient mice were detected for the percentage of haploidentical MHC matched mouse origin cells in the peripheral blood cells and checked daily for the appearance of GVHD symptoms. Histopathological examination of multiple organs from moribund mice was used to evaluate the grades of GVHD. Results: Recipient mice infused with 10 × 106 haploidentical MHC matched SPLCs and 5×106 syngeneic splenocytes showed a higher level and more stable chimerism with GVHD Ⅱ degree histopathological alterations. Histopathological results of GVHD in other group's hosts were not obvious, and the levels of chimerism were unstable. All of the mice survived over 150 d. Conclusion:The proportion and dose of syngeneic and haploidentical MHC splenocytes are of importance for inducing stable engraftment on the basis of nonlethal GVHD and to balance GVHD and HVGR.展开更多
将千里光全草粉用体积分数70%乙醇浸泡,经超声波-微波处理,用乙醚萃取脱色,冷冻真空干燥,制备千里光提取物冻干粉(SCE)。以对乙酰氨基酚为对照,采用醋酸扭体法和热板法研究不同剂量SCE的镇痛作用;采用骨髓微核试验研究不同剂量SCE的致...将千里光全草粉用体积分数70%乙醇浸泡,经超声波-微波处理,用乙醚萃取脱色,冷冻真空干燥,制备千里光提取物冻干粉(SCE)。以对乙酰氨基酚为对照,采用醋酸扭体法和热板法研究不同剂量SCE的镇痛作用;采用骨髓微核试验研究不同剂量SCE的致突变作用。结果发现,122.72 m g/kg SCE具有显著的镇痛作用,而130.90 m g/kg SCE对雌雄小白鼠均不具有致突变作用。说明122.72-130.90 m g/kg SCE能同时满足无致突变作用和显著镇痛作用的双重条件。展开更多
基金This work was supported by grants from the Ministry of Science and Technology of Taiwan,China(MOST 106-2314-B-182A-048-MY3)Chang Gung Medical Foundation(CMRPG3B0261,CMRPG6F0601-3,and CMRPG3C121-3).
文摘The role of the vascularized bone marrow component as a continuous source of donor-derived hematopoietic stem cells that facilitate tolerance induction of vascularized composite allografts is not completely understood.In this study,vascularized composite tissue allograft transplantation outcomes between recipients receiving either conventional bone marrow transplantation(CBMT)or vascularized bone marrow(VBM)transplantation from Balb/c(H2d)to C57BL/6(H2b)mice were compared.Either high-or low-dose CBMT(1.5×10^(8)or 3×10^(7)bone marrow cells,respectively)was applied.In addition,recipients were treated with costimulation blockade(1 mg anti-CD154 and 0.5 mg CTLA4Ig on postoperative days 0 and 2,respectively)and short-term rapamycin(3 mg/kg/day for the first posttransplant week and then every other day for another 3 weeks).Similar to high-dose conventional bone marrow transplantation,5/6 animals in the vascularized bone marrow group demonstrated long-term allograft survival(>120 days).In contrast,significantly shorter median survival was noted in the low-dose CBMT group(~64 days).Consistently high chimerism levels were observed in the VBM transplantation group.Notably,low levels of circulating CD4^(+)and CD8^(+)T cells and a higher ratio of Treg to Teff cells were maintained in VBM transplantation and high-dose CBMT recipients(>30 days)but not in low-dose VBM transplant recipients.Donor-specific hyporesponsiveness was shown in tolerant recipients in vitro.Removal of the vascularized bone marrow component after secondary donor-specific skin transplantation did not affect either primary allograft or secondary skin graft survival.
基金Supported by the National Natural Science Foundation of China,No.82060299Medical Discipline Leader Project of Yunnan Provincial Health Commission,No.D-2019020+5 种基金Yunnan Provincial Government Ten Thousand Person-Top Young Talents Project,No.KH-SWRQNBJ-2019-002Clinical Medical Center of the First People’s Hospital of Yunnan Province,No.2021LCZXXF-XZ04 and No.2022LCZXKF-HX05Kunming Medical Joint Special Project-Outstanding Youth Cultivation Project,No.202101AY070001-034Kunming Medical Joint Special Project,No.202101AY070001-272Famous Doctor Project of“Xingdian Talent Support Plan”of Yunnan Province,No.XDYC-MY-2022-0037Yunnan Province 2023 Undergraduate Education and Teaching Reform Research Project,No.2023BKXJJG-F04002.
文摘BACKGROUND Heart transplantation is a crucial intervention for severe heart failure,yet the challenge of organ rejection is significant.Bone marrow mesenchymal stem cells(BMSCs)and their exosomes have demonstrated potential in modulating T cells,dendtitic cells(DCs),and cytokines to achieve immunomodulatory effects.DCs,as key antigen-presenting cells,play a critical role in shaping immune responses by influencing T-cell activation and cytokine production.Through this modulation,BMSCs and their exosomes enhance graft tolerance and prolonging survival.AIM To explore the immunomodulatory effects of exosomes derived from BMSCs overexpressing microRNA-540-3p(miR-540-3p)on cardiac allograft tolerance,focusing on how these exosomes modulating DCs and T cells activity through the CD74/nuclear factor-kappaB(NF-κB)pathway.METHODS Rat models were used to assess the impact of miR-540-3p-enhanced exosomes on immune tolerance in cardiac allografts.MiR-540-3p expression was manipulated in BMSCs,and derived exosomes were collected and administered to the rat models post-heart transplantation.The study monitored expression levels of major histocompatibility complex II,CD80,CD86,and CD274 in DCs,and quantified CD4^(+)and CD8^(+)T cells,T regulatory cells,and cytokine profiles.RESULTS Exosomes from miR-540-3p-overexpressing BMSCs lead to reduced expression of immune activation markers CD74 and NF-κB p65 in DCs and T cells.Rats treated with these exosomes showed decreased inflammation and improved cardiac function,indicated by lower levels of pro-inflammatory cytokines(interleukin-1β,interferon-γ)and higher levels of anti-inflammatory cytokines(interleukin-10,transforming growth factorβ1).Additionally,miR-540-3p skewed the profiles of DCs and T cells towards immune tolerance,increasing the ratio of T regulatory cells and shifting cytokine secretion to favor graft acceptance.CONCLUSION Exosomes derived from BMSCs overexpressing miR-540-3p significantly enhance immune tolerance and prolong cardiac allograft survival by modulating the CD74/NF-κB pathway,which regulates activities of DCs and T cells.These findings highlight a promising therapeutic strategy to improve heart transplantation outcomes and potentially reduce the need for prolonged immunosuppression.
文摘Objective: A murine model of mixing syngeneic and haploidentical major histocompatibility complex (MHC) matched bone marrow cells transplant was used to evaluate the effect of splenocytes in graft-versus-host disease (GVHD) and host-versus-graft reaction (HVGR). Methods: BALB/C recipient mice were lethally conditioned with 8.5 Gy and injected with different grafts which consisted of syngeneic bone marrow cells plus splenocytes (SPLCs) and haploidentical MHC matched bone marrow cells (BMCs)plus different doses of splenocytes. Recipient mice were detected for the percentage of haploidentical MHC matched mouse origin cells in the peripheral blood cells and checked daily for the appearance of GVHD symptoms. Histopathological examination of multiple organs from moribund mice was used to evaluate the grades of GVHD. Results: Recipient mice infused with 10 × 106 haploidentical MHC matched SPLCs and 5×106 syngeneic splenocytes showed a higher level and more stable chimerism with GVHD Ⅱ degree histopathological alterations. Histopathological results of GVHD in other group's hosts were not obvious, and the levels of chimerism were unstable. All of the mice survived over 150 d. Conclusion:The proportion and dose of syngeneic and haploidentical MHC splenocytes are of importance for inducing stable engraftment on the basis of nonlethal GVHD and to balance GVHD and HVGR.
文摘将千里光全草粉用体积分数70%乙醇浸泡,经超声波-微波处理,用乙醚萃取脱色,冷冻真空干燥,制备千里光提取物冻干粉(SCE)。以对乙酰氨基酚为对照,采用醋酸扭体法和热板法研究不同剂量SCE的镇痛作用;采用骨髓微核试验研究不同剂量SCE的致突变作用。结果发现,122.72 m g/kg SCE具有显著的镇痛作用,而130.90 m g/kg SCE对雌雄小白鼠均不具有致突变作用。说明122.72-130.90 m g/kg SCE能同时满足无致突变作用和显著镇痛作用的双重条件。
