TCF1highPD-1+Ly108+CD8+ T Cells Are Associated with Graft Preservation in Sensitized Mice Treated with Non-Fc Receptor-Binding CD3 Antibodies.

The non-Fc-binding anti-CD3 Ab [anti-CD3F(ab')2] can induce graft acceptance depending on the therapeutic window in a rodent heart transplant model. The delayed protocol allows for early graft infiltration of lymphocytes, which may behave in an inhibitory manner. We investigated the most effective protocol for anti-CD3F(ab')2 in sensitized conditions to confirm the evidence for clinical application. C57BL/6 mice were sensitized with BALB/c tail skin grafts and transplanted with BALB/c heart grafts at 8-12 wk after sensitization. Fifty micrograms of anti-CD3F(ab')2 was administered daily for 5 consecutive days on days 1-5 (day 1 protocol) or days 3-7 (delayed protocol). In nonsensitized mice, the delayed protocol significantly prolonged graft survival after transplantation from BALB/c to naive B6 (median survival time [MST], >100 d). In contrast, the delayed protocol was unable to prevent graft rejection in sensitized mice (MST, 5 d). A significantly increased percentage of granzyme B+ CD8+ T cells was observed in the graft on day 3 posttransplantation in sensitized conditions. Further, the day 1 protocol significantly prolonged graft survival (MST, 18 d), even in sensitized conditions. Day 1 treatment significantly increased the percentage of Foxp3+CD25+CD4+ T cells and phenotypically changed CD8+ T cells in the graft (i.e., caused a significant increase in the proportion of Ly108+TCF1highPD-1+CD8+ T cells). In conclusion, different timings of delayed anti-CD3F(ab')2 treatment promoted allograft preservation in association with phenotypic changes in CD4+ and CD8+ T cells in the graft under sensitized conditions.

Post-transplant donor-specific anti-HLA antibodies with a higher mean fluorescence intensity are associated with graft fibrosis in pediatric living donor liver transplantation.

The roles of post-transplant anti-HLA donor specific antibody (DSA) in pediatric liver transplantation (LT), including therapeutic strategies, remain controversial. This study aimed to identify the risks of post-transplant DSA for graft fibrosis progression in pediatric living donor LT (LDLT). We retrospectively evaluated 88 LDLT pediatric cases between December 1995 and November 2019. DSAs were assessed with single antigen bead test. Graft fibrosis was histopathologically scored with METAVIR and the centrilobular sinusoidal fibrosis system. Post-transplant DSAs were detected in 37 (52.9%) cases at 10.8 (1.3-26.9) years post-LDLT. The histopathological examination of 32 pediatric cases with post-transplant DSA revealed that 7 (21.9%) with a high DSA-MFI (≥9,378) showed graft fibrosis progression (≥F2). No graft fibrosis was observed in the subjects with a low DSA-MFI. The risk factors for developing graft fibrosis in pediatric cases with post-transplant DSA were an older graft age (>46.5 years old), lower platelet count (<10.7 × 104/ml) and higher Fib4 index (>0.7807, recipient age; >1.8952, donor age). Limited efficacy of additional immunosuppressants was observed in DSA positive pediatric cases. In conclusion, pediatric cases with a high DSA-MFI and risk factors should undergo a histological examination. The appropriate treatment for post-transplant DSA in pediatric LT needs to be determined.

Functional roles of graft-infiltrating lymphocytes during early-phase post-transplantation in mouse cardiac transplantation models.

Immunological behavior of graft-infiltrating lymphocytes (GILs) determines the graft fate (i.e., rejection or acceptance). Nevertheless, the functional alloreactivity and the phenotype of GILs at various times during the early post-transplantation phase have not been fully elucidated. We examined the immunological activities of early-phase GILs using a murine model of cardiac transplantation. GILs from 120-h allografts, but not 72-h allografts, showed robust activation and produced proinflammatory cytokines. In particular, a significant increase in CD69+ T-bet+ Nur77+ T cells was detected in 120-h allografts. Furthermore, isolated GILs were used to reconstitute BALB/c Rag2-/- γc-/- (BRG) mice. BRG mice reconstituted with 120-h GILs displayed donor-specific immune reactivity and rejected donor strain cardiac allografts; conversely, 72-h GILs exhibited weak anti-donor reactivity and did not reject allografts. These findings were confirmed by re-transplantation of cardiac allografts into BRG mice at 72-h post-transplantation. Re-transplanted allografts continued to function for >100 days, despite the presence of CD3+ GILs. In conclusion, the immunological behavior of GILs considerably differs over time during the early post-transplantation phase. A better understanding of the functional role of early-phase GILs may clarify the fate determination process in the graft-site microenvironment.

Triazolopyrimidine derivative NK026680 and donor-specific transfusion induces CD4+CD25+Foxp3+ T cells and ameliorates allograft rejection in an antigen-specific manner.

We have previously demonstrated the unique properties of a new triazolopyrimidine derivative, NK026680, which exerts immunosuppressive effects in rat heart transplant model and confers tolerogeneic properties on ex vivo-conditioned dendritic cells in mice. We herein demonstrate that NK026680 promotes the expansion of regulatory T cells (Tregs) with potent immunoregulatory effects when used in combination with donor-specific transfusion (DST). BALB/c (H-2d) heart graft were transplanted into C57BL/6 (H-2b) mice following intravenous injection of donor splenocytes (DST) and oral administration of NK026680. The NK026680 plus DST treatment markedly prolonged the survival time of the donor-graft, but not that of the 3rd party-graft (C3H; H-2k). Treg cells in the recipient spleen on day 0 expanded when stimulated with donor-antigens in vivo and in vitro. After heart transplantation, Treg cells accumulated into the graft and increased in the spleen. NK026680 plus DST also decreased activated CD8+ T cells in the spleen and inhibited infiltration of CD8+ T cells into the graft. Depletion of CD25+ cells inhibited the graft prolonging effect of the NK026680 plus DST treatment. NK026680 administration together with DST induces potent immunoregulatory effects in an antigen-specific manner, likely due to the in vivo generation of donor-specific Tregs.

A rare case of cavernous hemangioma accompanied with diffuse hepatic hemangiomatosis.

BACKGROUND: Hepatic cavernous hemangioma (CH) is the most common hepatic benign tumor. Most cases are solitary, asymptomatic, and found incidentally. In symptomatic cases with rapidly growing tumors and coagulopathy, surgical treatment is considered. In rare cases, diffuse hepatic hemangiomatosis (DHH) is reported as a comorbidity. The etiology of DHH is unknown. CASE PRESENTATION: A 29-year-old female patient had a history of endometriosis treated with oral contraceptives. Hepatic CH was incidentally detected in the segment IVa of the liver according to the Couinaud classification. Follow-up computed tomography (CT) and ultrasound sonography showed the growth of the lesion and formation of multiple new lesions near the first. Enhanced CT and magnetic resonance imaging (MRI) revealed that the new lesions were different from CH. Although oral contraceptives were stopped, all lesions grew in size. Malignancy and possibility of rupture of these tumors were considered due to the clinical course, and we opted for surgical removal of the tumors. Left liver lobectomy and cholecystectomy were performed. Surgical findings were small red spot spreading and a mass in segment IV of the liver. Pathological examination revealed a circumscribed sponge-like tumor with diffuse irregular extension to the adjacent area. Both of the lesions consisted of blood-filled dilated vascular spaces lined by flat endothelium without atypia. The diagnosis was hepatic CH with DHH. The patient was discharged on postoperative day 12 uneventfully. CONCLUSION: We report the successful resection of CH with DHH. The case findings suggest a relationship between oral contraceptive use and enlargement of CH and DHH. Although DHH has been poorly understood, a few previously published cases reported DHH occurrence in patients using oral contraceptives. In such cases, the decision to perform surgical resection should be made after careful examination.

[A Case of Surgical Resection of a Combined Hepatocellular and Cholangiocarcinoma with Hemobilia from Intraductal Tumor Thrombus].

We report a case of combined hepatocellular and cholangiocarcinoma with hemobilia. A 65-year-old man was admitted to our hospital because of pain in the right hypochondralrigion. Abdominal ultrasonography revealed bile duct dilatation in the lateral segment of liver and blood test findings showed elevation of the hepatobiliary enzyme, so ERC was performed and hemorrhage from the duodenal papilla was observed. In cholangiography, dilation of the left hepatic bile duct and filling defect were observed, and in the peroral cholangioscopy, a hemorrhagic papillary elevated lesion was identified in the left hepatic bile duct and diagnosed as adenocarcinoma as a result of biopsy. Left hepatectomy with caudate lobe, extrahepatic bile duct resection, lymph node dissection was performed by diagnosis of intrahepatic cholangiocarcinoma. In the resected specimen, tumor size was 16 mm, which was found in the left hepatic duct and invasived into the liver parenchyma. Histopathological examination revealed a combined hepatocellular and cholangiocarcinoma. Gemcitabin was administered as adjuvant chemotherapy for 8 months, but 1 year and 8 months after the operation, it recurred in the liver. Gemcitabin was administered, but it became PD, now it has changed to S-1 and it is SD for 2 years.

[Four Cases of Gastrointestinal Perforation Associated with Bevacizumab].

Four cases of gastrointestinal perforation associated with bevacizumab(BEV)were examined. Case 1: A 82-year-old male received FOLFIRI plus BEV for recurrent liver metastasis after rectal cancer resection. A lower esophageal perforation occurred 22 days after BEV administration and drainage was performed. Case 2: A 69-year-old female received FOLFOX4 plus BEV for unresectable rectal cancer and liver and lung metastasis. A rectal perforation occurred 6 days after BEV administration and suturing closure of the hole and colostomy was performed. Case 3: A 69-year-old female, received carboplatin(CBDCA) plus pemetrexed(PEM)plus BEV for unresectable left lung cancer and adrenal gland and lymph node metastasis. A small intestinal perforation occurred 15 days after BEV administration and ileocecal resection and primary anastomosis was performed. Case 4: A 73-year-old female received CBDCA plus PEM plus BEV for unresectable left lung carcinoma and pleural metastasis. A diverticulum of sigmoid colon perforation occurred 30 days after BEV administration and suturing closure of the hole and colostomy was performed. When we observe fever, abdominal pain, elevation of the inflammatory reaction after BEV administration, we should immediately examine gastrointestinal perforation.