BACKGROUND: The interaction between killer immunoglobulin-like receptors (KIRs) and HLA class I regulates natural killer (NK) cell cytotoxicity and function. The impact of NK cell alloreactivity through KIR in liver transplantation remains unelucidated. Since the frequency of HLA-C and KIR genotypes show ethnic differences, we assessed the impact of HLA-C, KIR genotype, or KIR-ligand mismatch on the allograft outcome of Korean liver allografts. METHODS: One hundred eighty-two living donor liver transplant patients were studied. Thirty-five patients (19.2%) had biopsy-confirmed acute rejection (AR), and eighteen (9.9%) had graft failure. The HLA-C compatibility, KIR genotypes, ligand-ligand, and KIR-ligand matching was retrospectively investigated for association with allograft outcomes. RESULTS: Homozygous C1 ligands were predominant in both patients and donors, and frequency of the HLA-C2 allele in Koreans was lower than that in other ethnic groups. Despite the significantly lower frequency of the HLA-C2 genotype in Koreans, donors with at least one HLA-C2 allele showed higher rates of AR than donors with no HLA-C2 alleles (29.2% vs 15.7%, P=0.0423). Although KIR genotypes also showed ethnic differences, KIR genotypes and the number of activating KIR/inhibitory KIR were not associated with the allograft outcome. KIR-ligand mismatch was expected in 31.6% of Korean liver transplants and had no impact on AR or graft survival. CONCLUSIONS: This study could not confirm the clinical impact of KIR genotypes and KIR-ligand mismatch. However, we demonstrated that the presence of HLA-C2 allele in the donor influenced AR of Korean liver allografts.
Adult ; Alleles ; Asian Continental Ancestry Group/*genetics ; Female ; Genotype ; Graft Rejection ; Graft Survival ; HLA-C Antigens/*genetics ; Homozygote ; Humans ; Killer Cells, Natural/cytology/immunology ; Ligands ; *Liver Transplantation ; Male ; Middle Aged ; Proportional Hazards Models ; Receptors, KIR/chemistry/*genetics/metabolism ; Republic of Korea ; Tissue Donors ; Transplantation, Homologous

OBJECTIVETo establish a calculated panel reactive antibody (CPRA) method to analyze the donor-recipient incompatibility rate in PRA-positive kidney recipients and estimate the probability of these recipients to receive kidney transplantation.

METHODSBased on the database of HLA-A, -B, -DR genes and A-B, A-DR, B-DR, A-B-DR haplotype frequencies collected from 2004 donors from Jan 2000 to Dec 2012, we analyzed CPRA in 202 PRA-positive recipients and evaluated the consistency between PRA and CPRA assessments using a CPRA-Java calculator software, which returned a percentage of CPRA (representing the probability of unacceptable HLA in the donor group) after input of HLA-specific antibodies of a PRA-positive recipient.

RESULTSThe mean PRA intensity of the 202 PRA-positive recipients was (23.12∓17.83)% with a mean CPRA% of (46.07∓23.30)%. A significant difference was found between the mean PRA% and CPRA% in low sensitized recipients (PRA 0-10%) [(6.87∓2.41)% vs (21.63∓11.75)%, P<0.05) and in moderately sensitized recipients (PRA 10%-30%) [(20.15∓5.70)% vs (50.56∓16.86)%, P<0.05), but not in highly sensitized recipients (PRA>30%); The concordance rates between PRA% and CPRA% in the 3 groups were 19.35% (P<0.05), 10.99% (P<0.05), and 100% (P>0.05), respectively.

CONCLUSIONSLowly sensitized kidney recipients might have a lower probability of actually receiving a transplant than PRA% shows. A PRA%>30% is a risk factor for kidney transplantation. PRA reflects the sensitized level of a renal recipient, and reliable detection of HLA antibody specificity is of critical importance. CPRA accurately reflects the probability of a recipient to receive a transplant to assist clinicians in predicting the waiting time and selecting the transplant approach.

Antibodies ; Antibody Specificity ; Graft Rejection ; immunology ; Graft Survival ; immunology ; HLA Antigens ; genetics ; Haploidy ; Histocompatibility Testing ; methods ; Humans ; Kidney Transplantation

OBJECTIVETo evaluate the influence of major histocompatibility complex class I chain-related gene A (MICA) antibodies on acute rejection (AR) and renal function in early stage after renal transplantation.

METHODSA total of 197 renal transplant candidates admitted in Nanfang Hospital in 2009-2010 were enrolled in this study. MICA antibodies and their specificity were detected in all the patients, and 139 patients were followed up for early acute rejection (AR) and graft function after transplantation.

RESULTSMICA antibodies were positive before transplantation in 45 candidates (22.84%). Eleven specific MICA antibodies were identified, among which the frequency of MICA019 antibody (65.7%) was significantly higher than that of MICA015 (8.6%) and MICA017 (8.6%) (P<0.01). Eighteen patients with positive MICA antibodies were single-specific and 17 were polyspecific (51.4% vs 48.6% ). Of the 139 patients undergoing renal transplantation, 39 developed early AR (28.1%). Of the 45 candidates positive for MICA antibodies, 38 received renal transplantation and early AR occurred in 14 of them (36.8%); 101 of 152 candidates negative for MICA antibodies underwent renal transplantation, and 25 experienced early AR (24.8%).

CONCLUSIONMICA019 antibody is a frequent MICA antibody possibly due to the high frequency MICA019 gene in Chinese population.

Adult ; Antibodies ; immunology ; Antibody Specificity ; Female ; Graft Rejection ; immunology ; Graft Survival ; immunology ; Histocompatibility Antigens Class I ; genetics ; immunology ; Humans ; Kidney Transplantation ; Male ; Middle Aged

BACKGROUNDCostimulatory signals play a vital role in T cell activation. Blockade of costimulatory pathway by CTLA4Ig or CD40LIg have enhanced graft survival in experimental transplantation models yet mechanisms remain undetermined. We investigated the effects of CTLA4Ig and CD40LIg gene transfer on islet xenografts rejection in rats.

METHODSHuman islets were infected with recombinant adenoviruses containing CTLA4Ig and CD40LIg genes and implanted beneath the kidney capsule of diabetic rats. Levels of blood sugar, morphological changes, and survival of grafts were recorded. Expressions of CTLA4Ig, CD40LIg and insulin were detected by immunohistochemical staining and cytokines levels were quantified by enzyme-linked immunosorbent assay (ELISA).

RESULTSBlood glucose levels in transplant rats decreased to normal level on the 2nd day post transplantation. The mean blood glucose in the control group, CTLA4Ig transfected group, CD40LIg transfected group and CTLA4Ig + CD40LIg cotransfected group increased on days 8, 24, 21, 68, post transplantation respectively. The grafts in control group, CTLA4Ig transfected group, CD40LIg transfected group and CTLA4Ig + CD40LIg cotransfected group survived for (8 ± 1), (29 ± 4), (27 ± 3), and (74 ± 10) days, respectively. Survival in CTLA4Ig + CD40LIg cotransfected group was significantly longer. Survivals of CTLA4Ig transfected group and CD40LIg transfected group were significantly longer than control group. In control animals, serum interleukin-2 and tumor necrosis factor α concentration significantly increased within seven days post transplantation. Haematoxylin eosin staining of grafts showed live islets in situ of transplant rats without inflammatory cell infiltration. Immunohistochemical staining confirmed the expression of insulin at islets in all experimental groups.

CONCLUSIONSTransfer of CTLA4Ig and CD40LIg genes, especially the cotransfer of both, inhibits rejection of murine islet xenografts. Downregulated expressions of Th1 cells related cytokines might be related to the beneficial effects.

Abatacept ; Animals ; Enzyme-Linked Immunosorbent Assay ; Graft Rejection ; therapy ; Graft Survival ; genetics ; physiology ; Humans ; Immunoconjugates ; genetics ; metabolism ; Immunohistochemistry ; Insulin ; metabolism ; Islets of Langerhans Transplantation ; immunology ; methods ; Rats ; Recombinant Fusion Proteins ; genetics ; metabolism ; Transplantation, Heterologous ; immunology ; methods

Colchicine has been shown to regulate the expression of inflammatory gene, but this compound possesses much weaker anti-inflammatory activity. In this study, we synthesized a new colchicine derivative CT20126 and examined its immunomodulatory property. CT20126 was found to have immunosuppressive effects by inhibiting lymphocyte proliferation without cytotoxicity and effectively inhibit the transcriptional expression of the inflammatory genes, iNOS, TNF-alpha, and IL-1beta, in macrophages stimulated by LPS. This effect was nearly comparable to that of cyclosporine A. This compound also significantly suppressed the production of nitric oxide and Th1-related pro-inflammatory cytokines, IL-1beta, TNF-alpha, and IL-2, with minimal suppression of Th2-related anti-inflammatory cytokines IL-4 and IL-10 in the sponge matrix allograft model. Moreover, administration of CT20126 prolonged the survival of allograft skins from BALB/c mice (H-2d) to the dorsum of C57BL/6 (H-2b) mice. The in vivo immune suppressive effects of CT20126 were similar to that of cyclosporine A. These results indicate that this compound may have potential therapeutic value for transplantation rejection and other inflammatory diseases.
Animals ; Cell Line ; Colchicine/*analogs & derivatives/chemistry/*pharmacology ; Cytokines/*biosynthesis ; Female ; Gene Expression Regulation/drug effects ; Graft Survival/*drug effects ; Immunosuppression ; Interleukin-1beta/genetics/metabolism ; Lipopolysaccharides/pharmacology ; Lymphocyte Culture Test, Mixed ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Nitric Oxide/biosynthesis ; Nitric Oxide Synthase Type II/genetics/metabolism ; Skin Transplantation/*immunology ; Th1 Cells/*drug effects/immunology/metabolism ; Th2 Cells/*drug effects/immunology/metabolism ; Transplantation, Homologous ; Tumor Necrosis Factor-alpha/genetics/metabolism

Mesenchymal stem cells (MSC) are multipotent in nature and believed to facilitate the engraftment of hematopoietic stem cells (HSC) when transplanted simultaneously in animal studies and even in human trials. In this study, we transfected culture-expanded MSC with granulocyte macrophage-colony stimulating factor (GMCSF) and stem cell factor (SCF) cytokine genes and then cotransplanted with mononuclear cells (MNC) to further promote HSC engraftment. MNC were harvested from cord blood and seeded in long-term culture for ex vivo MSC expansion. A total of 1 x 10(7) MNC plus MSC/microliter were introduced to the tail vein of nonobese diabetic/severe combined immunodeficiency mice. After 6-8 weeks later, homing and engraftment of human cells were determined by flow cytometry and fluorescence in situ hybridization studies. The total nucleated cell count and the engraftment of CD45+/CD34+ cells and XX or XY positive human cells were significantly increased in cotransplanted mice and even higher with the cytokine gene-transfected MSC (GM-CSF>SCF, p<0.05) than in transplantation of MNC alone. These results suggest that MSC transfected with hematopoietic growth factor genes are capable of enhancing the hematopoietic engraftment. Delivering genes involved in homing and cell adhesions, CXCR4 or VLA, would further increase the efficiency of stem cell transplantation in the future.
Transfection/*methods ; Stem Cell Factor/genetics/*metabolism ; Mice, SCID ; Mice ; Mesenchymal Stem Cells/*metabolism ; Mesenchymal Stem Cell Transplantation/*methods ; Hematopoietic Stem Cell Transplantation/*methods ; Granulocyte Macrophage Colony-Stimulating Factors, Recombinant/*metabolism ; Graft Survival/*immunology ; Genetic Enhancement/methods ; Animals

OBJECTIVE: To explore the role of combined heart-thymus transplantation for heart allograft in rats. METHODS: Vascularized heart-thymus combined transplantation was performed with microsurgical technique. Graft survival, histopathology, infiltration of CD4+, CD8+ T cells, level and mRNA expressions of IL-2 and IL-4 in the serum and cardiac grafts were investigated. RESULTS: Heart allograft in the controls had a survival time of (6.0+/-0.76) d. heart-thymus combined transplantation in non-thymectomized rats had a survival time of (6.88+/-0.64)d (P<0.05). Heart-thymus combined transplantation in thymectomized rats led to an evident survival time of (14.13+/-5.82)d (P<0.01) for cardiac graft, which further obtained long term survival after short course of treatment with cyclosporine. Pathologic lesion and infiltration of CD4+ and CD8+ T cells in cardiac grafts showed mitigated in the long term survival group. IL-2 level in the serum and cardiac grafts maintained low level in the long term survival group, whereas IL-4 maintained high level. CONCLUSION Whether thymectomized or not in recipient rats, heart-thymus combined transplantation has a positive effect to protect cardiac graft. Furthermore, in thymectomized rats heart-thymus combined transplantation may lead to evident survival prolongation of the heart grafts, which induces immune tolerance in short course of treatment with cyclosporine.
Animals ; CD4-Positive T-Lymphocytes ; immunology ; CD8-Positive T-Lymphocytes ; immunology ; Cyclosporine ; therapeutic use ; Graft Survival ; drug effects ; immunology ; Heart Transplantation ; Immune Tolerance ; drug effects ; immunology ; Immunosuppressive Agents ; therapeutic use ; Interleukin-2 ; blood ; genetics ; Interleukin-4 ; blood ; genetics ; Male ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; Reverse Transcriptase Polymerase Chain Reaction ; Thymectomy ; Thymus Gland ; transplantation ; Time Factors ; Transplantation Immunology ; immunology ; Transplantation, Homologous

Our previous study has demonstrated that there is a significant delay of Balb/c cardiac allograft rejection in the C57BL/6 4-1BB-deficient knockout recipient. In this study, we examined the effect of combined blockade of the 4-1BB and CD28 costimulatory pathways on cardiac allograft rejection in the C57BL/6-->Balb/c model. A long-term cardiac allograft survival was induced in CD28/4-1BB- deficient mice (>100 days survival in 3 of 4 mice), which was comparable with CD28-deficient mice (>100 days survival in 2 of 5 mice; P<0.2026). There was no long-term cardiac allograft survival in either wild-type (WT) or 4-1BB-deficient mice, even though 4-1BB-deficient recipients showed a significant delay of cardiac allograft rejection than WT mice. An in vitro mixed leukocyte reaction (MLR) assay showed that 4-1BB-deficient and WT mouse T cells had a similar responsiveness to allostimulation, whereas CD28- and CD28/4-1BB-deficient mouse T cells had a defective responsiveness to allostimulation. Furthermore, 4-1BB-deficient mice showed a similar CTL but an elevated Ab response against alloantigens as compared to WT mice, and the alloimmune responses of 4-1BB-deficient mice were abrogated in the CD28-deficient background. Overall, these results indicate that the CD28 costimulatory pathway plays a major role in the alloimmune response and that 4-1BB signals are dependent upon CD28 signals.
Transplantation, Homologous/immunology ; Signal Transduction/*immunology ; Mice, Knockout ; Mice ; Isoantigens/immunology ; Heart Transplantation/immunology ; Graft Survival/immunology ; Cytotoxicity Tests, Immunologic ; Antigens, CD28/genetics/*immunology/metabolism ; Antibodies/immunology ; Animals ; 4-1BB Ligand/deficiency/genetics/*immunology/metabolism

We examined the effect of class II transactivator (CIITA) down-modulation on allograft rejection. To inhibit the function of CIITA, we constructed a series of CIITA mutants and found one exhibiting the dominant-negative effect on the regulation of major histocompatibility complex (MHC) class II expression. To test whether the CIITA dominant-negative mutant reduces immunogenecity, CIITA-transfected melanoma cells were injected into allogeneic host and assessed for immune evading activity against host immune cells. We demonstrated that the CIITA dominant-negative mutant allowed tumor nodules to develop earlier in the lung than control by this tumor challenge study. Furthermore, skin grafts deficient for CIITA also survived longer than wild-type in allogeneic hosts. Both the tumor challenge and skin graft studies suggest the inhibition of CIITA molecules in donor tissue would be beneficial to the control of allo-response.
Transplantation, Homologous ; Transfection ; Trans-Activators/genetics/*immunology/metabolism ; Trans-Activation (Genetics)/genetics/immunology ; Skin Transplantation ; Nuclear Proteins/genetics/*immunology/metabolism ; Mutation ; Mice, Transgenic ; Mice, Knockout ; Mice, Inbred C57BL ; Mice, Inbred BALB C ; Mice ; Melanoma, Experimental/genetics/immunology/pathology ; Male ; Interferon Type II/pharmacology ; Humans ; Histocompatibility Antigens Class II/genetics/*immunology/metabolism ; Graft Survival/genetics/immunology ; Graft Rejection/genetics/*immunology ; Genes, MHC Class II/genetics/immunology ; Flow Cytometry ; DNA, Complementary/genetics ; Cell Proliferation/drug effects ; Cell Line, Tumor ; Animals

OBJECTIVETo investigate the role of simultaneous blockade of CD40/CD40L and B7/CD28 pathways in the immune tolerance via co-expression of sCD40LIg and CTLA4Ig mediated by replication-defective adenovirus.

METHODSAd-sCD40LIg-IRES(2)-CTLA4Ig, replication-defective adenovirus co-expressing sCD40LIg and CTLA4Ig, was constructed and identified. The co-expression of sCD40LIg and CTLA4Ig was evaluated with confocal laser scanning microscope and Western blotting. Skin transplantations of C57BL/6 to BALB/c mice were performed. PBS, Ad-Shuttle-CMV and Ad-sCD40LIg-IRES(2)-CTLA4Ig were administered. Skin graft survival was monitored and the mRNA expression of both genes was evaluated in the skin allografts.

RESULTSAd-sCD40LIg-IRES(2)-CTLA4Ig was constructed successfully and identified. The co-expression of sCD40LIg and CTLA4Ig was identified with confocal laser scanning microscopy and Western blotting. Compared to the skin graft mean survival time (MST) of non-treated group ((5.75+/-0.71) d) or Ad-Shuttle-CMV-treated group ((5.50+/-0.53) d), the skin graft MST was dramatically prolonged in the Ad-sCD40LIg-IRES(2)-CTLA4Ig-treated group ((16.38+/-1.19) d, P<0.001). The mRNA expression of both genes was detected.

CONCLUSIONAd-sCD40LIg-IRES(2)-CTLA4Ig, a replication-defective adenovirus carrying genes encoding sCD40LIg and CTLA4Ig, was constructed. Simultaneous blockade of CD40/CD40L and B7/CD28 costimulatory pathway mediated by replication-defective adenovirus significantly prolonged skin allograft survival in mice.

Abatacept ; Adenoviridae ; genetics ; Animals ; Cytopathogenic Effect, Viral ; Graft Survival ; immunology ; Immunoconjugates ; genetics ; immunology ; metabolism ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; RNA, Messenger ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology ; Reverse Transcriptase Polymerase Chain Reaction ; Skin Transplantation ; immunology ; methods ; Transfection