The induced pluripotent stem cells (iPSCs), derived by ectopic expression of reprogramming factors in somatic cells, can potentially provide unlimited autologous cells for regenerative medicine. In theory, the autologous cells derived from patient iPSCs should be immune tolerant by the host without any immune rejections. However, our recent studies have found that even syngeneic iPSC-derived cells can be immunogenic in syngeneic hosts by using a teratoma transplantation model (Nature 474:212-215, 2011). Recently two research groups differentiated the iPSCs into different germ layers or cells, transplanted those cells to the syngeneic hosts, and evaluated the immunogenicity of those cells. Both of the two studies support our conclusions that some certain but not all tissues derived from iPSCs can be immunogenic, although they claimed either "negligible" or "lack of" immunogenicity in iPSC derivatives (Nature 494:100-104, 2013; Cell Stem Cell 12:407-412, 2013). To test the immunogenicity of clinically valuable cells differentiated from human iPSCs are emergently required for translation of iPSC technology to clinics.
Animals ; Cell Cycle Proteins ; metabolism ; Cell Transplantation ; methods ; Graft Rejection ; immunology ; Induced Pluripotent Stem Cells ; immunology ; transplantation ; Membrane Proteins ; metabolism ; Mice, Knockout ; Teratoma ; immunology ; metabolism

OBJECTIVETo study the roles of granzyme B and perforin in diagnosing acute rejection after liver transplantation, and the relationship between their activity index (AI) and Banff's histological grading criteria.

METHODSLiver biopsies were processed as for routine surgical specimens and labeled with granzyme B and perforin monoclonal antibodies. The number of positive cells/mm(2) was determined as activity index (AI) by IPP image analysis software. Histologic findings were used as the "gold standard" in diagnosing acute rejection.

RESULTSOf 41 liver biopsy samples studied, acute rejection was noted in 21 cases, the remaining 20 cases showed no evidence of rejection. The AI of granzyme B and perforin in the acute rejection group was significantly higher than that in the non-acute rejection group (< 0.001). In the acute rejection group, the AI in moderate to severe acute rejection was higher than that in mild to indeterminate acute rejection (< 0.001). Compared with the "golden" histologic criteria, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of granzyme B in diagnosing acute rejection were 90.0%, 95.2%, 94.7%, 90.9% and 92.7% respectively. The values of these parameters for perforin were also above 80%.

CONCLUSIONSGranzyme B and perforin are key markers of activated immune cells in acute rejection and highly expressed during acute liver rejection episodes. As ancillary investigations, these parameters demonstrated high sensitivity and specificity in diagnosing acute rejection in allograft post-transplant liver biopsies.

Biomarkers ; Biopsy ; Graft Rejection ; diagnosis ; metabolism ; Granzymes ; metabolism ; Humans ; Liver ; metabolism ; pathology ; Liver Transplantation ; immunology ; Membrane Glycoproteins ; metabolism ; Perforin ; Pore Forming Cytotoxic Proteins ; metabolism ; Sensitivity and Specificity

In allogeneic transplantation, including the B6 anti-BALB.B settings, H60 and H4 are two representative dominant minor histocompatibility antigens that induce strong CD8 T-cell responses. With different distribution patterns, H60 expression is restricted to hematopoietic cells, whereas H4 is ubiquitously expressed. H60-specific CD8 T-cell response has been known to be dominant in most cases of B6 anti-BALB.B allo-responses, except in the case of skin transplantation. To understand the mechanism underlying the subdominance of H60 during allogeneic skin transplantation, we investigated the dynamics of the H60-specific CD8 T cells in B6 mice transplanted with allogeneic BALB.B tail skin. Unexpectedly, longitudinal bioluminescence imaging and flow cytometric analyses revealed that H60-specific CD8 T cells were not always subdominant to H4-specific cells but instead showed a brief dominance before the H4 response became predominant. H60-specific CD8 T cells could expand in the draining lymph node and migrate to the BALB.B allografts, indicating their active participation in the anti-BALB.B allo-response. Enhancing the frequencies of H60-reactive CD8 T cells prior to skin transplantation reversed the immune hierarchy between H60 and H4. Additionally, H60 became predominant when antigen presentation was limited to the direct pathway. However, when antigen presentation was restricted to the indirect pathway, the expansion of H60-specific CD8 T cells was limited, whereas H4-specific CD8 T cells expanded significantly, suggesting that the temporary immunodominance and eventual subdominance of H60 could be due to their reliance on the direct antigen presentation pathway. These results enhance our understanding of the immunodominance phenomenon following allogeneic tissue transplantation.
Animals ; Antigen Presentation ; Antigen-Presenting Cells/immunology/metabolism ; CD8-Positive T-Lymphocytes/*immunology ; Epitopes, T-Lymphocyte/*immunology ; Female ; Graft Rejection/*immunology ; Interferon-gamma ; Lymphocyte Activation/immunology ; Lymphocyte Count ; Mice ; Minor Histocompatibility Antigens/*immunology/metabolism ; *Skin Transplantation ; Transplantation, Homologous

OBJECTIVETo investigate the expression of mucosal addressin cell adhesion molecule-1(MAdCAM-1) during small bowel graft rejection and the effects of MAdCAM-1 on the development of acute rejection.

METHODSRat heterotopic small bowel transplantation (SBT) was performed in F344/N rats with syngeneic and allogeneic (BN-F344/N) grafts. Bowel and gut-associated lymphoid tissue(GALT) samples were collected from small bowel transplants on postoperative day(POD) 1, 3, 5 and 7. Histopathology assessment of the grafts was conducted to identify the rejection. MAdCAM-1 was detected by immunohistochemistry and Western blot.

RESULTSDuring acute rejection, MAdCAM-1 was highly-expressed on gut lamina propia and GALTs, particularly on vascular endothelial cells in the gut lamina propia. There were no change of MAdCAM-1 expression in syngeneic grafts from POD1 to POD7. In allogeneic grafts, MAdCAM-1 expression in mesenteric lymph nodes was down-regulated, while up-regulated on the vascular endothelial cells in the lamina propria during acute rejection.

CONCLUSIONAlteration of MAdCAM-1 expression may be associated with the development of SBT graft rejection.

Animals ; Graft Rejection ; immunology ; metabolism ; Graft Survival ; Immunoglobulins ; metabolism ; Intestinal Mucosa ; immunology ; Intestine, Small ; transplantation ; Lymph Nodes ; metabolism ; Lymphoid Tissue ; Male ; Mucoproteins ; metabolism ; Rats ; Rats, Inbred BN ; Rats, Inbred F344

OBJECTIVETo gain insight into the role of Toll-like receptor 2 (TLR2) in graft rejection following penetrating keratoplasty, and investigate the expression of TLR2 mRNA in the corneal graft.

METHODSPenetrating keratoplasty was performed in 3 groups of rats for orthotopic autologous corneal transplantation (group A), allograft corneal transplantation (group B), or allograft corneal transplantation with hormone treatment (C). The transparency and neovascularization of the cornea were observed using a slit-lamp microscope and scored according to the rejection index, with normal cornea serving as the control. The corneal tissues were sampled at 5, 7, and 9 days after the transplantation for histopathological examination and detection of TLR2 mRNA expression using RT-PCR.

RESULTSWith the passage of time, edema, opacities and neovascularization of the corneal graft occurred after the operation in all the groups. Seven days after the operation, the rejection index of group B, but not that of groups A and C, met the diagnostic criteria for graft rejection with also support by histopathological evidence. The expression of TLR2 mRNA was detected in normal corneas and augmented in the corneal grafts in the 3 transplantation groups. TLR2 mRNA expression in group B was significantly higher than that of group A, and the expression in group C decreased significantly in comparison with that in group B (P<0.05).

CONCLUSIONAs the recognition receptors of native immune system, TLR2 in the rejected corneal grafts may recognize the allograft antigen and play a role in acute graft rejection after penetrating keratoplasty.

Animals ; Cornea ; metabolism ; Female ; Graft Rejection ; immunology ; Keratoplasty, Penetrating ; Postoperative Complications ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Toll-Like Receptor 2 ; genetics ; metabolism

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

OBJECTIVETo evaluate the association of major histocompatibility complex class I chain related gene A (MICA) antibodies with acute rejection (AR), chronic rejection (CR) and renal function after renal transplantation.

METHODSSerum MICA antibodies were detected with ELISA before and after transplantation with also examinations of panel reactive antibodies (PRA), serum creatinine, urine, graft ultrasound, lymphocyte subsets and the pathology of graft biopsy. The study was carried out in two parts to monitor MICA antibodies in acute and chronic rejections after renal transplantation.

RESULTSIn the first part of the study 18 of the 41 recipients experienced episodes of acute rejection, and the incidence rate was markedly higher in MICA(+) group than in MICA(-) group (P<0.05). Compared with the recipients with stable renal functions, the patients with acute graft rejection showed a significantly higher positivity rate of MICA antibodies. Postoperative MICA antibody monitoring showed that MICA antibody level increased gradually 2-3 days after the occurrence of acute rejection; anti-rejection treatment lowered serum creatinine to a normal level but MICA antibodies remained positive. In the second part, 21 of 40 patients had chronic graft rejection and showed significantly higher positivity rate of MICA than the patients with stable renal functions (P<0.05). In patients with chronic rejections, the serum creatinine levels were significantly higher in MICA(+) than in MICA(-) cases (P<0.05). Graft biopsy of all MICA(+) cases showed C4d deposition.

CONCLUSIONThe status of MICA antibodies can predict the occurrence and treatment outcomes of acute rejection, and also as one of the major causes of chronic graft rejection, they affect the long-term survival of the renal grafts.

Adolescent ; Adult ; Antibodies ; blood ; immunology ; Complement C4b ; metabolism ; Creatinine ; blood ; Follow-Up Studies ; Graft Rejection ; blood ; immunology ; pathology ; HLA Antigens ; immunology ; Histocompatibility Antigens Class I ; immunology ; Humans ; Kidney ; metabolism ; physiopathology ; Kidney Transplantation ; Peptide Fragments ; metabolism ; Young Adult

OBJECTIVETo investigate the mechanism of immune hyporesponsiveness induced by donor-antigen- unloaded recipient-derived immature dendritic cell (imDC) of liver grafts in rats.

METHODSForty Sprague-Dawley rats (donor) and forty male Wistar rats (recipient) were randomly divided into 4 groups: control, cyclosporine A (CsA), mature DC (mDC), and imDC groups respectively, with 10 donor rats and 10 recipient rats in each group. Recipient rats in CsA group were treated with 10 mg•kg⁻¹•d⁻¹ CsA starting day 2 after the transplantation. Recipients in the mDC or imDC groups were given Wistar rat derived mDCs (1 × 10⁶/rat) or imDCs (1 × 10⁶/rat) via dorsal vein of the penis respectively 1 day before the transplantation. In each group, 5 recipients were kept for determination of survival time and the other 5 rats were executed at day 10 after transplantation. Blood samples were collected for the measurement of serum alanine aminotransferase (ALT), total bilirubin (TBIL), interleukin 2 (IL-2), interferon gamma (IFN-γ), IL-4, and IL-10 levels. Liver tissue was harvested for HE staining and acute rejection evaluation. Expression levels of Fas-L/Fas in the grafts were detected by immunohistochemical staining; and Western blot was used to detect the expression level of Scurfin.

RESULTSThe survival time of CsA and imDC groups was significantly longer than that of control and mDC groups (all P < 0.05). The levels of serum ALT and TBIL in the control group (2072.20 ± 217.93 IU/L and 147.42 ± 22.02 µmol/L) and mDC group (2117.00 ± 285.13 IU/L and 141.58 ± 20.82 µmol/L) were significantly higher than those in the CsA group (59.68 ± 13.48 IU/L and 15.40 ± 2.13 µmol/L) or imDC group (50.80 ± 9.63 IU/L and 14.44 ± 3.49 µmol/L) (all P < 0.05). In the CsA and imDC groups, the levels of IL-2 (22.52 ± 3.75 pg/mL and 22.12 ± 3.90 pg/mL) and IFN-γ (309.20 ± 25.19 pg/mL and 321.00 ± 21.64 pg/mL) were significantly lower, but the levels of IL-4 (297.60 ± 25.07 pg/mL and 277.00 ± 22.47 pg/mL) and IL-10 (1226.00 ± 140.49 pg/mL and 1423.00 ± 106.39 pg/mL) were higher than those of the control (IL-2: 147.78 ± 12.80 pg/mL, IFN-γ: 1758.60 ± 106.22 pg/mL, IL-4: 17.40 ± 4.77 pg/mL, IL-10: 81.00 ± 9.47 pg/mL) and mDC groups (IL-2: 142.34 ± 9.29 pg/mL, IFN-γ: 1835.00 ± 82.63 pg/mL, IL-4: 15.60 ± 3.96 pg/mL, IL-10: 68.80 ± 11.23 pg/mL) (all P < 0.01). The expression level of Scurfin protein on CD4+ CD25+ T cells of the imDC group (1.34 ± 0.29) was significantly higher than that in the control (0.72 ± 0.13), CsA (0.37 ± 0.11), and mDC groups (0.78 ± 0.17) (all P < 0.05).

CONCLUSIONDonor-antigen-unloaded recipient-derived imDC is an effective treatment in inducing immune hyporesponsiveness through induction of T cell apoptosis, shift in Thl/Th2 balance, and proliferation of regulatory T cell.

Animals ; Antigens ; immunology ; Cytokines ; immunology ; Dendritic Cells ; cytology ; immunology ; transplantation ; Fas Ligand Protein ; immunology ; Forkhead Transcription Factors ; metabolism ; Graft Rejection ; immunology ; Graft Survival ; immunology ; Humans ; Immunity ; physiology ; Liver ; cytology ; immunology ; pathology ; Liver Transplantation ; immunology ; Male ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Rats, Wistar ; fas Receptor ; immunology

OBJECTIVETo investigate the expressions of matrix metalloprotein-2 (MMP-2) and tissue inhibitor of metallopeptidase inhibitor-1 (TIMP-1) in the renal allografts of patients with chronic active antibody-mediated rejection (ABMR), and explore their role in the pathogenesis of ABMR.

METHODSImmunohistochemistry and computer-assisted image analysis were used to detect the expression of MMP-2 and TIMP-1 in the renal allografts of 46 patients with interstitial fibrosis and tubular atrophy (IF/TA), with 15 normal renal tissue specimens as the control. The association of MMP-2 and TIMP-1 with the pathological grade of IF/TA in ABMR was analyzed.

RESULTSThe expressions of MMP-2 and TIMP-1 significantly increased in the renal tissues of the patients as compared with the normal renal tissues (P<0.05). MMP-2 expression tended to decrease, while TIMP-1 and serum creatinine increased with the pathological grades of IF/TA (P<0.05). In IF/TA group, the expression of TIMP-1 was positively correlated to serum creatinine level (r=0.718, P=0.00<0.05).

CONCLUSIONAbnormal expressions of MMP-2 and TIMP-1 can promote the development of renal fibrosis in chronic ABMR.

Adult ; Antibody Formation ; Complement C4b ; metabolism ; Female ; Fibrosis ; etiology ; Graft Rejection ; immunology ; Humans ; Kidney ; metabolism ; Kidney Diseases ; pathology ; Kidney Transplantation ; adverse effects ; immunology ; Male ; Matrix Metalloproteinase 2 ; genetics ; metabolism ; Middle Aged ; Peptide Fragments ; metabolism ; Tissue Inhibitor of Metalloproteinase-1 ; genetics ; metabolism

OBJECTIVETo review this efficacy and safety of bortezomib, a proteasome inhibitor, in the setting of the sensitized transplant candidate.

DATA SOURCESThe data used in this review were from articles published (PubMed) between 2000 to 2010. Additionally abstracts from medical meetings related to transplant were also used.

STUDY SELECTIONArticles were selected if they were trial results or case studies for the use of bortezomib in the sensitized patient population.

RESULTSThe early data using bortezomib as a part of desensitization regimens has shown success. Although one cycle (4 doses) of bortezomib seems to have affect on many patients, it also seems likely that to provide complete desensitization multiple cycles will be required. Regarding safety, bortezomib has been shown to have minimal side effects. The most common side effects reported are those of thrombocytopenia and anemia. These side effects are dose related and self limiting upon discontinuation of the treatment.

CONCLUSIONSBortezomib with plasmapheresis is a promising new alternative to desensitization protocols that use either high dose intravenous immune globulin (IVIG) or low dose IVIG and plasmapheresis. The efficacy on antibody reduction looks to be batter that that of the IVIG based regimens without significant addition toxicity. The results of ongoing prospective trials are positive and their complete results are greatly anticipated.

Boronic Acids ; therapeutic use ; Bortezomib ; Graft Rejection ; immunology ; prevention & control ; Humans ; Protease Inhibitors ; therapeutic use ; Proteasome Endopeptidase Complex ; metabolism ; Pyrazines ; therapeutic use ; Transplants ; adverse effects