Elevation of microRNA-214 is associated with progression of liver fibrosis in patients with biliary atresia.

BACKGROUND: MicroRNAs (miRNAs) play an important role in regulating fibrogenesis in the liver. The current study examined the ability of microRNA-214 (miR-214) level in liver and serum samples obtained from patients with BA to predict progressive liver fibrosis in patients with biliary atresia (BA). METHODS: We examined miR-214 level in relation to conventional markers of liver fibrosis, with liver and serum samples from BA patients. Fifty-two patients with BA who underwent Kasai portoenterostomy and four control patients underwent liver biopsy. In 28 patients with BA, blood samples were collected to analyze circulating serum miR-214. RESULTS: MiR-214 levels in liver tissue were significantly upregulated in patients with BA who had severe liver fibrosis (F3-4) compared to those with none to mild fibrosis (F0-2), whereas suppressors-of-fused homolog (Sufu) mRNA levels were significantly suppressed in F3-4. Serum miR-214 levels were significantly higher in patients with F3-4 compared with F0-2. Area under the curve analysis showed that the serum miR-214 cut-off level for predicting F3-4 was 0.805 (p = 0.0046). CONCLUSION: Hepatic overexpression of miR-214 is associated with progression of liver fibrosis in patients with BA, and the circulating miR-214 level may serve as a non-invasive predictor of liver fibrosis.

The risk factors for cholestasis in patients with duodenal atresia in a single institutional cohort.

PURPOSE: The etiology of cholestasis in neonates is associated with several factors including gastrointestinal disease and surgery. We aimed to identify the potential risk factors for perioperative cholestasis in patients with duodenal atresia and determine specific cutoff values for the risk factors. METHODS: This retrospective cohort study included 76 neonates diagnosed with duodenal atresia surgically treated during the neonatal period at our institution between January 1990 and March 2017. The neonates were categorized into two groups: those with and without cholestasis. Univariate and multivariate analyses were performed to identify the possible risk factors for cholestasis. RESULTS: Among the 76 neonates with duodenal atresia, 21 (27%) developed cholestasis. The duration of total parenteral nutrition was identified as a risk factor in univariate analysis; however, it was not an independent risk factor for cholestasis. Gestational age and highest C-reactive protein (CRP) values were independent risk factors, with adjusted odds ratios of 0.53 and 1.25, respectively. To predict the occurrence of cholestasis, the cutoff value for gestational age was 35.0 weeks, and highest CRP value was 2.4 mg/dL. CONCLUSIONS: The occurrence of cholestasis in patients with duodenal atresia was associated with preterm delivery and severity of the inflammatory response during the perioperative period.

Surgery for long tubular intestinal duplication with massive hemorrhage: a case report and literature review.

BACKGROUND: Long tubular duplication is a rare congenital intestinal disease, that can lead to emergency situations marked by massive hemorrhage. However, preoperative diagnosis and surgical treatment are challenging. This report presents preoperative images and details a surgical procedure for long tubular intestinal duplications with massive hemorrhage. CASE PRESENTATION: A 3-year-old boy presented to the emergency department with melena. Despite undergoing a Tc-99m pertechnetate scintigraphy one year prior, which revealed nonspecific findings with enhancement of some parts of the intestine, enhanced abdominal CT revealed an edematous small intestine with luminal extravasation. The patient received a transfusion of red blood cells; however, his hemoglobin level did not improve. Arterial angiography and double-balloon endoscopy revealed no remarkable findings. Exploratory laparotomy revealed a long tubular duplication in half of the small intestine. Utilizing the Wrenn procedure, we successfully removed all duplicate mucosa. Pathological findings showed that almost all duplications contained gastric mucosa and revealed an ulcer with a ruptured arterial vessel. His symptoms were resolved, and the hemoglobin level stabilized. At 2 months postoperatively, no surgical complications were present. CONCLUSIONS: Effective management of long tubular duplications with massive hemorrhage involves timely application of the Wrenn procedure. Recognition of specific imaging findings is crucial to prompt exploratory laparotomy, ensuring optimal outcomes and preventing delays in treatment.

Potential risks associated with laparoscopic gastrostomy in patients with the COL4A1 variant: Two case reports.

The COL4A1 (collagen Type 4 alpha1) pathogenic variant is associated with porencephaly and schizencephaly and accounts for approximately 20% of these patients. This gene variant leads to systemic microvasculopathy, which manifests as brain, ocular, renal, and muscular disorders. However, only a few patients with surgical interventions have been reported and the potential surgical risks are unknown. Here, we present the cases of two female patients between 7 and 8 years of age who were diagnosed with the COL4A1 variant and underwent laparoscopy-assisted percutaneous endoscopic gastrostomy (LAPEG) for oral dysphagia. Their primary brain lesions were caused by porencephaly and paralysis, which are caused by multiple cerebral hemorrhages and infarctions, and both patients had refractory epileptic complications. Although LAPEG was successfully performed in both patients without any intraoperative complications, one patient developed alveolar hemorrhage postoperatively and required mechanical ventilation. Thus, careful perioperative management of patients with the COL4A1 variant is important.

Intestinal volvulus in utero causing torsion of dilated bowel with ileal atresia: a case report.

BACKGROUND: In utero intestinal volvulus with intestinal atresia is a rare and life-threatening condition that can cause torsion of the dilated bowel. The management and outcomes of this disease remain unclear. CASE PRESENTATION: A 19-year-old woman noticed a decrease in fetal motion at 35 weeks. Fetal ultrasound showed dilated fetal bowel and the whirlpool sign. The patient was referred to our hospital for an emergency cesarean section. The neonate's abdomen was dark and severely distended, and a laparotomy was performed. Necrotic ileum and cord-type intestinal atresia (Type II) were observed in the dilated terminal ileum. The necrotic ileum was resected, and a second-look surgery was performed the following day. Then, we anastomosed the remaining intestine, and the total intestine length was 52 cm. There were no surgical complications, and the patient was discharged without requiring total parenteral nutrition or fluid infusion. The patient's height and weight were within the - 2 standard deviation range of the growth curve at 5 months. CONCLUSIONS: Emergency and appropriate management of intestinal volvulus in utero causing torsion of the dilated bowel resulted in good outcomes in a patient with intestinal atresia. Perinatal physicians should be aware of this emergency condition and plan their treatment approach accordingly.

Long-Term Outcome After Tacrolimus-Related Neurotoxicity in Pediatric Living Donor Liver Transplantation.

BACKGROUND: Tacrolimus-related neurotoxicity is a serious complication. Posterior reversible encephalopathy syndrome, which is severe neurotoxicity after pediatric living donor liver transplantation (LDLT), is a medication-induced complication related to calcineurin inhibitors. The purpose of this study was to evaluate the long-term outcome of tacrolimus-related neurotoxicity after pediatric LDLT. METHODS: Pediatric patients who underwent LDLT between 2007 and 2020 at our institution and developed neurologic symptoms with tacrolimus were included in the study. Tacrolimus-related encephalopathy was defined as encephalopathy that resolved after tacrolimus was discontinued. All patients received tacrolimus and a steroid for immunosuppression starting just after LDLT. RESULTS: During the study period, 128 patients underwent LDLT. All patients received tacrolimus and a steroid. Six patients (5%) developed tacrolimus-related encephalopathy. The median age at transplant was 1.6 years. The original diseases were biliary atresia (n = 5) and progressive familial intrahepatic cholangiopathy type 2 (n = 1). Patients developed encephalopathy at a median of 9 days after LDLT. All patients recovered with conversion to cyclosporine. Posterior reversible encephalopathy syndrome was confirmed by magnetic resonance imaging in 3 patients. The mean tacrolimus level at encephalopathy was 11 ng/dL (range, 5.6-14.6 ng/dL). White blood cell count elevation was observed in all patients. One patient died of pancreatitis. Surviving patients (n = 5) were followed for a median of 9 years. All patients resumed tacrolimus a median of 8 months from onset. No neurologic complications were observed after resuming tacrolimus. CONCLUSION: We observed tacrolimus-induced encephalopathy in 5% of patients after pediatric LDLT. Patients can resume tacrolimus safely without further neurologic symptoms.

A Retransplant Case for Hepatopulmonary Syndrome Without Liver Cirrhosis or Portosystemic Shunt After Living-Donor Liver Transplantation: A Case Report.

Hepatopulmonary syndrome (HPS) is a disease of gas exchange caused by intrapulmonary shunting secondary to liver disease-associated intrapulmonary vascular dilation. HPS is characterized by the triad of cirrhosis, chronic liver disease, or portosystemic shunting (PSS); arterial hypoxemia; and intrapulmonary arteriovenous shunting in the absence of a primary cardiopulmonary anomaly. We encountered a rare case of HPS without liver disease or PSS. The patient was an 8-year-old girl who underwent living donor liver transplantation (LDLT) shortly after developing fulminant hepatitis at 11 months of her age. Eight years after LDLT, hypoxemia and shortness of breath developed. The shunt ratio on 99mTc-macroaggregated albumin (MAA) lung perfusion scintigraphy (99mTc-MAA lung scan) was 32%. The patient had no cardiopulmonary disease, so we diagnosed her illness as HPS. We did not find cirrhosis, chronic liver disease, or PSS as a cause of HPS. We thought the graft was the cause of HPS. A second transplantation was planned. One year after the diagnosis of HPS, the shunt ratio on 99mTc-MAA lung scan worsened to 42%, digital clubbing appeared, and hypoxemia was worsening. Thus, we performed a second LDLT. After LDLT the shunt ratio on 99mTc-MAA lung scan normalized (6%) and cyanosis resolved. We determined that the graft was the cause of HPS; the typical causes of HPS were not clearly revealed in the histologic examination of the second liver explant. Acute rejection occurred twice after LDLT, so we speculated that HPS occurred because the graft became stressed over the long term.

Impact of Monosegment Graft Use for Infants in Pediatric Living Donor Liver Transplantation.

BACKGROUND: Left lateral segment grafts are generally used for very young pediatric patients undergoing living donor liver transplantation (LDLT). Recently, graft reduction techniques were developed for LDLT. Monosegment grafting has been used in newborns. The aim of this study was to determine the usefulness of monosegment grafting for infants. METHODS: Recipients <2 years of age who underwent LDLT with a monosegment graft between 2010 and 2020 were gathered. Parents comprised all LDLT donors. A segment 2 monosegment graft was resected as a graft from the donor. Standard liver volume (SLV) was estimated using Urata's equation. Graft type, graft weight (GW), and native liver weight were assessed. RESULTS: Eight patients were included in the study. Original diseases consisted of biliary atresia (n = 6) and fulminant hepatitis (n = 2). Final graft type included monosegment (n = 5) and reduced monosegment (n = 3). Median final GW/body weight after reduction was 3% (range, 2%-3.4%). Median native liver weight/SLV was 134% except in patients with fulminant hepatitis. Median pre-reduction graft volume (GV)/estimated GV was 113% (range, 60%-208%). Median pre-reduction GV/SLV of monosegment grafts that required reduction (n = 3) was 109% (range, 106%-121%). Median final reduced graft GV/SLV was 80% (range, 74%-91%). Complications due to large-for-size grafts were not observed. One case of bile leakage due to graft reduction occurred as a complication. Grafts were functioning well with the exception of one graft loss due to antibody-mediated rejection. CONCLUSION: Estimated GV in infants varies widely. Monosegment grafting can be useful for infants as well as newborns.

Prenatally diagnosed accessory scrotum: A case report and review of the literature on prenatal features.

Accessory scrotum (AS) is rarely diagnosed antenatally, and its prenatal features remain unknown. Here, we report a case of a prenatally diagnosed accessory scrotum with perineal lipoma. A 33-year-old woman was referred to our hospital at 35 weeks of gestation to evaluate a mass in the fetal perineal region. Prenatal ultrasonography showed a 2.0 × 2.0 cm sized, echogenic, and circular mass located posterior to the left scrotum in a male fetus. Magnetic resonance imaging (MRI) showed a mass containing adipose tissue. A 6.5 cm elastic mass (AS and protruding lipoma) was observed in the perineal region, and surgical excision was performed at 8 months of age. Histological examination confirmed the diagnosis of AS with perineal lipoma, and there was no recurrence at follow-up. The typical prenatal presentation of AS was a circular perineal mass located posterior to the normal scrotum and was associated with perineal lipoma. The prenatal detection of AS was feasible with careful observation via ultrasonography, and prenatal MRI was useful in characterizing perineal tumors and evaluating associated anomalies.

Suppression of xenogeneic innate immune response by a membrane-type human surfactant protein-A.

Macrophage-mediated xenogeneic rejection is a major immunological obstacle. We recently reported that membrane-type surfactant protein-D (SP-D) on swine endothelial cells (SECs) suppressed macrophage-mediated rejection. Similar to SP-D, the carbohydrate recognition domain of surfactant protein-A (SP-A) can induce inhibitory signals in effector cells. The present study aimed to examine the suppressive effect of SP-A on macrophage-mediated xenogeneic rejection. Naive SECs and SPA-transfected SECs (SEC/SP-A) were co-cultured with THP-1 cells and cytotoxicity was evaluated. To investigate the effect of SP-A on phagocytosis, human macrophages were co-cultured with SEC or SEC/SP-A, and the extent of phagocytosis and production of reactive oxygen species were assessed via flow cytometry. The mRNA expression levels of inflammatory cytokines in macrophages were determined using reverse transcription-PCR. Additionally, the effects of THP-1-Lucia NF-κB cells on transcription factors were evaluated. The cytotoxicity and phagocytosis of SEC/SP-A were significantly decreased compared with those of naive SEC. Furthermore, the co-culture of human macrophages with SEC/SP-A decreased reactive oxygen species production, and the mRNA expression levels of TNFα were decreased in macrophages, whereas those of IL-10 were increased. In addition, NF-κB transcription was decreased in SEC/SP-A compared with that in SEC. In conclusion, the ectopic expression of human SP-A in porcine cells represents an attractive method for suppressing macrophage-mediated cytotoxicity.

Clinical implications of serum autotoxin in regular follow up after pediatric living donor liver transplantation for biliary atresia.

BACKGROUND: Pediatric patients sometimes develop graft fibrosis after living donor liver transplant (LDLT). Autotaxin is a recently developed serum marker for hepatic fibrosis. We studied the relationship between serum autotaxin levels and histological findings in patients after LDLT for biliary atresia (BA). METHODS: Information on patients aged <19 years who received LDLT for BA and were followed for at least 1 year after LDLT was gathered. Autotaxin levels were compared with pathological fibrosis scores. RESULTS: The study included 52 patients, of whom 4 patients had no fibrosis (F0), 36 patients had F1 fibrosis, and 12 patients had F2. The median serum autotaxin level was 0.89 mg/L. In patients with portal vein (PV) complications such as stenosis or thrombosis (n = 7), the mean autotoxin level was 1.25 mg/L compared with 0.95 mg/L in patients without PV complications (p = 0.004). Among patients without PV complications, the mean autotaxin level was 0.90, 0.88, and 1.18 mg/L in F0, F1, and F2 fibrosis, respectively. The mean autotaxin was higher in F2 fibrosis than in F0 or F1 fibrosis (p<0.05). Autotoxin had a high area under the curve (0.86) with the cut-off level of 0.897 mg/L. CONCLUSION: Serum autotaxin is a novel marker for liver fibrosis in patients after pediatric LDLT for BA. TYPE OF STUDY: Study of Diagnostic Test. LEVEL OF EVIDENCE: Level II.

Early Use of Everolimus as a Third Immunosuppressive Agent for Intestinal Transplantation: A Report of 2 Cases.

BACKGROUND: In patients with intestinal transplantation (ITx), renal function is easily impaired because of long-term parenteral nutrition and side effects of tacrolimus. Everolimus was used in patients with renal insufficiency in our study. METHODS: We administered everolimus as a third immunosuppressive agent in addition to tacrolimus and steroids for renal sparing in patients who received ITx. We assessed everolimus levels, complications, and renal function. RESULTS: Two patients received everolimus after ITx. Patient 1 was a 13-year-old boy who underwent ITx for an allied disorder of Hirschsprung's disease. After induction therapy with rabbit antithymocyte globulin, maintenance therapy consisted of tacrolimus and steroids. Everolimus was introduced 3 months after ITx for renal sparing. Seven months later, the patient required partial intestinal graft resection owing to bowel obstruction. Everolimus was suspended for only 2 weeks. Four years after ITx, the trough level of tacrolimus was maintained at 3 to 5 ng/mL. The trough level of everolimus was maintained at 3 to 5 ng/mL. Patient 2 was a 32-year-old man who underwent deceased ITx for short gut syndrome. Induction and maintenance immunosuppression was the same as for patient 1. Everolimus was introduced 1 month after surgery. Two years after ITx, trough levels of tacrolimus and everolimus were the same as in patient 1. No rejection was observed in either patient, and renal function was well maintained. We observed no side effects caused by everolimus. CONCLUSIONS: Everolimus could be used safely and effectively after ITx. Early use of everolimus after ITx did not affect wound healing.

Long-Term Outcome of Portal Vein Stenting After Pediatric Living Donor Liver Transplantation.

BACKGROUND: Portal vein (PV) stenosis is sometimes seen in pediatric living donor liver transplantation (LDLT). PV stents have been attempted in adults with persistent stenosis. However, long-term usefulness of PV stenting is unknown because stents do not expand with growth. We investigated the effect and long-term outcome of PV stenting for stenosis after pediatric LDLT. METHODS: We included patients aged <18 years who underwent LDLT from 1998 to 2020 and who underwent PV stenting for stenosis. We assessed age at procedure, stent complications, and long-term outcomes. RESULTS: Five patients underwent PV stent placement. The median age at LDLT was 10 years (range, 0.8-18.1 years). The median interval between LDLT and stent placement was 25 months. The median age at stent placement was 16 years (range, 3-20 years). The median body weight was 38 kg (range, 13-63 kg). The median stent diameter was 8 mm. The median observation period after stent placement was 8 years. On average, body weight increased 1.6 times. One complication associated with stent placement was PV thrombosis, which resulted in stent failure, but we observed no portal hypertension. In the other 4 patients, the stent has remained functioning, and there was no clinical evidence of portal hypertension. CONCLUSIONS: PV stents are effective for intractable PV stenosis in children. PV stents were successfully placed in children as young as 3 years old and weighing 13 kg. Our data suggests that a stent placed in young children does not cause portal hypertension as patients grow.

Study of the CRISPR/Cas3 System for Xenotransplantation.

The CRISPR/Cas3 system, classified in class I system, was recently focused as a new technology. For application of this system to porcine cells, the plasmids of bpNLS-Cascade, BPNLS-hCas3, and pBS-U6icrRNA were prepared. Initially, 2 crRNAs were established in the exon 9 of pig Gal-T (GGTA1) as #45 and #86. Next, hCas3 + #45 + #86 (group 1, control), Cascade + hCas3 + #45 (group 2), Cascade + hCas3 + #86 (group 3), and Cascade + hCas3 + #45 + #86 (group 4) were set and transfected into pig fibroblasts. Transfected cells were analyzed for bulk expression of α1,3Gal epitope by fluorescence-activated cell sorting (FACS), using a GSI-B4 lectin 2 days after the transfection. As the results, changes of expression are observed in order of G4>G2>G3, indicating the effect of the Cas3 system. Therefore, the nested polymerase chain reaction (PCR) for target region of GGTA1 was performed. Next, the PCR products from each group were checked in blotting, and the products were placed into the cloning sit of TOPO vector and transformed into Escherichia coli. Sixteen colonies of each group were checked by PCR, and clones containing PCR product with slightly varying length were evaluated. The direct sequence of these PCR changes were demonstrated as 294 to 754 bp deletions. In conclusion, we confirmed the effect of the CRISPR/Cas3 system on pig cell, especially in xenotransplantation.

Successful Surgical Resection and Chemotherapy for Unresectable Hepatoblastoma With Pulmonary Metastases and for Lung Recurrence After Liver Transplantation: A Case Report.

BACKGROUND: Liver transplantation (LTx) is indicated for unresectable hepatoblastoma (HB) without distal metastasis. However, to our knowledge, there is no consensus on the management of unresectable HB with pulmonary metastases, or on the treatment of recurrent HB. We report a successful case of metastatic HB treated with repeated lung resection, chemotherapy, and LTx. This study strictly complied with the Helsinki Congress and the Istanbul Declaration regarding donor source. CASE REPORT: Our case was a 1-year-old boy who developed pre-treatment extent of disease (PRETEXT) Ⅲ HB with multiple pulmonary metastases. The liver tumor was unresectable because it involved all hepatic veins. After 3 cycles of chemotherapy (cisplatin/carboplatin plus doxorubicin), the remaining 2 pulmonary metastases were resected and living donor liver transplantation (LDLT) was performed. Five months after LDLT, a tumor recurrence was detected in the right lung. Repeat lung resection was performed followed by 1 cycle of chemotherapy (carboplatin plus doxorubicin). There has been no recurrence for 18 months since the last lung resection. DISCUSSION: Previous reports revealed that 14 patients, including the present case, underwent LTx after resection of metastatic HB pulmonary lesions. Of these patients, the 2-year survival rate after LTx was 91%. Recurrence was reported in 5 patients, 2 of whom were successfully treated with repeated resection of the metastatic lesions. LTx after resection of lung recurrence may be a potential treatment for unresectable HB with pulmonary metastases.

A study of the mechanisms responsible for the action of new immunosuppressants and their effects on rat small intestinal transplantation.

In a series of studies, using an identical rat intestinal transplantation model, we evaluated the effects of several drugs. FK-506 caused a significant attenuation in the proliferation of allogeneic CD4+ T cells and IFN-γ secreting effector functions. FYT720 resulted in a marked reduction in the numbers of lymphocytes, associated with a reduction of T cell recruitment, in grafts. An anti-MAdCAM antibody was next reported to significantly down-regulate CD4+ T cell infiltration in intestinal grafts by blocking the adhesion molecule, and could be useful as an induction therapy. Concerning TAK-779, this CCR5 and CXCR3 antagonist diminished the number of graft-infiltrating cells by suppressing the expression of their receptors in the graft. As a result, it reduced the total number of recipient T cells involved in graft rejection. As the next step, we focused on the participation of monocytes/ macrophages in this field. PQA-18 has been the focus of a novel immunosuppressant that attenuates not only the production of various cytokines, such as IL-2 & TNF-α, on T cells, but the differentiation of macrophages by inhibiting PAK2 as well. In this report, we summarize our previous studies not only regarding the above drugs, but on an anti-complement drug and a JAK inhibitor as well.

Efficacy of a 365 nm Ultraviolet A1 light Emitting Diode (UVA1-LED) in in vitro Extracorporeal Photopheresis.

Extracorporeal photochemotherapy (ECP) is one of the more effective cell therapies for graft-versus-host disease (GvHD). ECP is a widely recommended therapeutic approach for the treatment of chronic GvHD, particularly steroid-refractory GVHD. In recent years, the use of a light emitting diode (LED) in the clinic has attracted considerable interest. In this study, we examined the issue of whether an ultraviolet A1-light emitting diode (UVA1-LED) can be used as a light source in ECP. To compare the efficacy of ECP with conventional UVA lamp and a UVA1-LED, we established an in vitro ECP model. Treatment efficacy was evaluated by measuring the % apoptosis and the inhibition of T-cell proliferation. To investigate the effect of ECP on the innate immune reaction, THP-1 cells with a luciferase reporter gene driven by a NF-kB response element (THP-1 luc NF-kB) were treated with ECP. The LED-ECP induced apoptosis and inhibition of T-cell proliferation as efficiently as a conventional ECP. However, LED-ECP induced less innate immunity in THP-1. Since LED devices are more compact compared with conventional UVA irradiation devices, the use of a UVA1-LED in the treatment of ECP may be a better alternative to conventional ECP therapy.

Suppression of macrophage-mediated xenogeneic rejection by the ectopic expression of human CD177.

Cellular xenogeneic rejection by the innate immune system is a major immunological obstruction that needs to be overcome for the successful clinical use of xenografts. Our focus has been on macrophage-mediated xenogeneic rejection, since suppressing macrophage function has considerable potential for practical applications in the area of xenotransplantation. We report herein on an investigation of the suppressive effect of human CD177 (hCD177) against macrophage-mediated xenogeneic rejection. Wild type swine aortic endothelial cell (SEC) and an SEC transfectant with hCD177 (SEC/hCD177) were co-cultured with macrophages, and the degree of cytotoxicity was evaluated by WST-8 assays, and phagocytosis was examined using Calcein-AM labeling methods. The expression of anti/pro-inflammatory cytokines was evaluated by RT-qPCR and the phosphorylation of SHP-1 on macrophages in co-culture was evaluated by Western blotting. The result of cytotoxicity assays indicated that hCD177 suppressed M1 macrophage-mediated xenogeneic rejection (vs. SEC, p < 0.0001). Similarly, the result of phagocytosis assays indicated that hCD177 suppressed it (vs. SEC, p < 0.05). In addition, hCD177 significantly suppressed the expression of IL-1ß, a pro-inflammatory cytokine, in M1 macrophages (vs. SEC, p < 0.01). Luciferase assays using THP1-Lucia NF-kB also showed a significant difference in NF-kB activation (vs. SEC, p < 0.001). In addition, hCD177 was found to induce the phosphorylation of SHP-1 in M1 macrophages (vs. SEC, p < 0.05). These findings indicate that hCD177 suppresses M1 macrophage-mediated xenogeneic rejection, at least in part via in the phosphorylation of SHP-1.

Aspects of the Complement System in New Era of Xenotransplantation.

After producing triple (Gal, H-D and Sda)-KO pigs, hyperacute rejection appeared to no longer be a problem. However, the origin of xeno-rejection continues to be a controversial topic, including small amounts of antibodies and subsequent activation of the graft endothelium, the complement recognition system and the coagulation systems. The complement is activated via the classical pathway by non-Gal/H-D/Sda antigens and by ischemia-reperfusion injury (IRI), via the alternative pathway, especially on islets, and via the lectin pathway. The complement system therefore is still an important recognition and effector mechanism in xeno-rejection. All complement regulatory proteins (CRPs) regulate complement activation in different manners. Therefore, to effectively protect xenografts against xeno-rejection, it would appear reasonable to employ not only one but several CRPs including anti-complement drugs. The further assessment of antigens continues to be an important issue in the area of clinical xenotransplantation. The above conclusions suggest that the expression of sufficient levels of human CRPs on Triple-KO grafts is necessary. Moreover, multilateral inhibition on local complement activation in the graft, together with the control of signals between macrophages and lymphocytes is required.