Survey on attitudes toward brain-dead and living donor transplantation in medical students: a cross-sectional study in Japan.

BACKGROUND: Although a shortage in organ donation is a critical problem in Japan, understanding of and attitude toward organ transplantation in medical students have not been sufficiently reported. METHODS: Between 2013 and 2018, we surveyed 702 medical students in the fifth-year clinical training in our urology department. The survey concerned (1) knowledge of Japanese transplantation law, which was amended in 2010, and (2) whether the respondents had an organ donor card and had agreed to be a brain-dead donor or a living donor in kidney transplantation with specific reasons for their choices. RESULTS: All 702 students answered the survey. Of 657 students who provided valid answers to the first section, 402 (61%) recognized the amendment to the Japanese transplantation law, and only 11 (1.7%) fully understood its contents. Of 702 students, 194 (28%) had a donor card, 384 (55%) agreed to be a brain-dead donor, and 529 (75%) agreed to be a living donor in kidney transplantation. As the specific reasons for their choices, only a few medical students wrote reasons based on their medical standpoint, and more students wrote emotional reasons. CONCLUSIONS: The understanding of and attitude toward organ transplantation were not remarkably high in the fifth-year medical students in Japan. To solve the donor shortage problem, education about organ transplantation may need to be more effective.

Impact of distance between donor and recipient hospitals on cadaveric kidney transplantation outcomes.

BACKGROUND: The impact of distance between donor and recipient hospitals on outcomes in cadaveric kidney transplantations is unknown. We investigated the association between inter-hospital distance and outcomes in cadaveric kidney transplantations in Japan. METHODS: We retrospectively analyzed 363 cadaveric kidney transplantations between 2002 and 2017 in Japan. Inter-hospital distance, graft transport time, total ischemic time (TIT), and graft survival were compared between our hospital and national transplantation cohort in Japan. Estimated glomerular filtration rate (eGFR) 1 month and 1 year after transplantation was compared between cadaveric and living-donor kidney transplantations in our hospitals. Additionally, inter-hospital distances among the seven geographical regions in Japan were assessed. RESULTS: There were 12 and 351 cadaveric kidney transplantations at our hospital and in Japan, respectively. Mean inter-hospital distance at our hospital (217 ± 121 km) was significantly longer than that of the national cohort (53 ± 80 km; P < 0.001). Mean TIT and graft survival for our hospital and national cohort were 539 ± 200 min and 91% and 491 ± 193 min and 81%, respectively. Mean eGFRs 1 year after cadaveric and living-donor transplantations at our hospitals were comparable (47 ± 16 vs. 47 ± 15 mL/min/1.73 m2). The comparison among seven regions in Japan indicated a regional difference in inter-hospital distance with an association between area (km2) and inter-hospital distance (km). CONCLUSIONS: Despite the longer inter-hospital distance at our hospital, TIT and transplant outcomes were acceptable in our cases. In addition, geographical inequity in graft allocation in Japan was suggested.

Daclatasvir/asunaprevir based direct-acting antiviral therapy ameliorate hepatitis C virus-associated cryoglobulinemic membranoproliferative glomerulonephritis: a case report.

BACKGROUND: Direct-acting antivirals (DAAs) dramatically improve the treatment of hepatitis C virus (HCV) infections. However, the effects of DAAs on extra-hepatic manifestations such as HCV-associated glomerulonephritis, especially in cases with renal dysfunction, are not well elucidated. CASE PRESENTATION: A 69-year-old Japanese woman was diagnosed as having chronic hepatitis C, genotype 1b at the age of 55. She presented with hypertension, microscopic hematuria, proteinuria, renal dysfunction, purpura, and arthralgia at the age of 61. She also had hypocomplementemia and cryoglobulinemia. Renal biopsy revealed membranoproliferative glomerulonephritis (MPGN), and she was diagnosed as having HCV-associated cryoglobulinemic MPGN. She declined interferon therapy at the time and was treated with antihypertensive medications as well as oral corticosteroid that were effective in reducing proteinuria. However, when the corticosteroid dose was reduced, proteinuria worsened. She began antiviral treatment with daclatasvir/asunaprevir (DCV/ASV). Clearance of HCV-RNA was obtained by 2 weeks and sustained, and liver function was normalized. In addition, microhematuria turned negative, proteinuria decreased, hypocomplementemia and estimated glomerular filtration rate were improved, whereas cryoglobulinemia persisted. She completed 24 weeks of therapy without significant adverse effects. CONCLUSION: In a case of HCV-associated cryoglobulinemic MPGN with renal dysfunction, DCV/ASV -based DAAs ameliorated microhematuria, proteinuria and renal function without significant side effects.

NF-κB-dependent increase in tissue factor expression is responsible for hypoxic podocyte injury.

BACKGROUND: Fibrin deposition within glomeruli is commonly seen in kidney biopsy specimens, suggesting enhanced coagulant activity. Tissue factor (TF) is a coagulation factor which is also related to various biological effects, and TF is upregulated by hypoxia in cancer cells. Recently, hypoxic podocyte injury has been proposed, therefore, we investigated TF expression in hypoxia. METHODS: Conditionally immortalized human podocytes were differentiated and treated under hypoxic or normoxic conditions. mRNA expressions of TF and tissue factor pathway inhibitor (TFPI) were analyzed by quantitative RT-PCR. Protein levels of TF and TFPI were tested by enzyme-linked immunosorbent assay. We employed small interfering RNA (siRNA) to temporary knockdown early growth response protein 1 (Egr-1), hypoxia-inducible factor-1α (HIF-1α) and TF. The expression of CD2-associated protein (CD2AP) mRNA and phalloidin staining was examined to assess podocyte injury. RESULTS: Hypoxia increased mRNA expression of TF (6 h: 2.3 ± 0.05 fold, p < 0.001, 24 h: 5.6 ± 2.4 fold, p < 0.05) and suppressed TFPI (6 h: 0.54 ± 0.04 fold, p < 0.05, 24 h: 0.24 ± 0.06 fold, p < 0.001) compared with normoxia. Similarly, protein levels of TF were increased and TFPI were decreased. Egr-1 siRNA did not change TF mRNA expression. Pyrrolidine dithiocarbamate (PDTC), a nuclear factor kappa B (NF-κB) inhibitor, significantly reduced hypoxia induced TF expression, and HIF-1α knockdown further increased TF. Hypoxia resulted in decreased CD2AP and actin reorganization in podocytes, and these changes were attenuated by TF siRNA. CONCLUSION: Hypoxia increased the expression of TF in human podocytes NF-κB dependently. TF may have a critical role in the hypoxic podocyte injury.

A case of membranoproliferative glomerulonephritis associated with curved fibril deposition.

BACKGROUND: It is sometimes challenging to diagnose unsusual cases of fibrillary glomerulonephritis (FGN) and immunotactoid glomerulopathy (ITG), the rare causes of nephrotic syndrome. CASE PRESENTATION: A 75-year-old Japanese woman presented with nephrotic syndrome, microhematuria and renal insufficiency. Renal biopsy revealed membranoproliferative glomerulonephritis (MPGN) with IgM and weak C3 deposition. Congo red stain was negative. Electron microscopy demonstrated massive fibrils in the subendothelium, mesangium and subepithelium. The fibrils were partially parallel, partially curved and 17 nm in diameter. Cryoglobulin, hepatitis B virus (HBV) antigen, hepatitis C virus (HCV) antibody or antinuclear antibody were negative. CONCLUSION: We report a case of MPGN associated with peculiar non-amyloid fibril deposition corresponding to neither FGN nor ITG.

Incidence of postoperative cytomegalovirus and BK-polyoma virus infections and graft loss in ABO-incompatible renal transplant recipients: a multicenter retrospective study.

OBJECTIVES: The current study aimed to examine the incidence of perioperative infections and graft viability in ABO-compatible and ABO-incompatible renal transplant recipients. METHODS: We included 643 living donor renal transplant recipients registered in the Michinoku Renal Transplant Network from 1998 to 2021. Patients were divided into the ABO-compatible and ABO-incompatible kidney transplantation groups. We compared the characteristics of the two groups and evaluated the incidence of postoperative viral infections (cytomegalovirus and BK virus), graft loss-free survival, and overall survival between the two groups. RESULTS: Of 643 patients, 485 (75%) and 158 (25%) were ABO-compatible and ABO-incompatible renal transplant recipients, respectively. Postoperative viral infections, rituximab use, and plasma exchange were significantly more common in ABO-incompatible than in ABO-compatible transplant recipients. However, there were no significant differences in terms of other background characteristics. The ABO-incompatible group was more likely to develop viral infections than the ABO-compatible group. Graft loss-free survival and overall survival did not significantly differ between the two groups. According to the multivariate Cox regression analysis, ABO compatibility was not significantly associated with graft loss-free survival and overall survival. CONCLUSION: Although the incidence of postoperative viral infections in ABO-incompatible renal transplant recipients increased, there was no significant difference in terms of rejection events, graft loss-free survival, and overall survival.

Role of High-sensitivity C-reactive Protein in Future Cardiovascular Events in Hemodialysis Patients.

BACKGROUND/AIM: The pathogenesis of cardio-vascular disease (CVD) in hemodialysis (HD) patients involves inflammation and oxidative stress. High-sensitivity C-reactive protein (hs-CRP) is an established inflammatory biomarker associated with CVD. Several studies have suggested that the inflammatory biomarker pentraxin-3 (PTX-3) and the oxidative stress-related biomarker soluble lectin-like low-density lipoprotein receptor-1 (sLOX-1) are novel biomarkers for CVD in non-HD populations. This study aimed to clarify the association of these established and novel biomarkers with future cardiovascular (CV) events in HD patients. PATIENTS AND METHODS: This was a single-center prospective cohort study that included 255 HD patients. The primary outcome was the composite of nonfatal and fatal CV events. The event-free survival rate between the two groups according to the median plasma level of each biomarker at baseline was evaluated using the Kaplan-Meier method. The risk for CV events at elevated levels of each biomarker was estimated using Cox proportional hazard model. RESULTS: We observed 44 CV events during the median follow-up period of 743 days. The event-free survival rate significantly differed between the two groups in hs-CRP but not in PTX-3 or sLOX-1. The unadjusted hazard ratio (HR) for CV events in patients with hs-CRP levels above the median was 2.63 [95% confidence interval (CI)=1.37-5.02]. The HR remained significant after adjusting for age, sex, history of CVD, and diabetes (HR=2.30; 95%CI=1.20-4.43). CONCLUSION: In HD patients, hs-CRP may have a predictable role for future CV events, whereas PTX-3 and sLOX-1 do not.

A case of myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA)-associated glomerulonephritis and concurrent membranous nephropathy.

BACKGROUND: Myeloperoxidase anti-neutrophil cytoplasmic antibody-associated glomerulonephritis (MPO-ANCA-GN) and concurrent membranous nephropathy (MN) are very rare combination. Their causal relationship has been suggested, but not determined. CASE PRESENTATION: A 73-years-old male with 5-year history of proteinuria underwent an operation for his sigmoid colon cancer. Seven months later, he was referred to a nephrology division due to an exacerbating renal function and hypoalbuminemia. Laboratory examination revealed positive MPO-ANCA in the serum. A renal biopsy revealed a necrotizing extracapillary proliferative glomerulonephritis with crescents, demonstrating MPO-ANCA-GN. Whereas, immunofluorescent staining documented granular deposition of immumoglobulin (Ig) G and C3 along the capillary wall and electron microscopy showed subepithelial deposits in the glomerular basement membrane demonstrating MN. Immunofluorescent staining of IgG subclass showed positive IgG1, IgG2, negative IgG3 and weak positive IgG4 suggested the possibility of malignancy-associated MN. CONCLUSION: Combination of MPO-ANCA-GN and MN are rare. Although the causal relationship has been suggested in some cases, we should consider all the possibilities including idiopathic MN and secondary MN associated with malignancy, drug use or infection.

Valacyclovir-associated acute kidney injury and encephalopathy in an elderly woman with normal kidney function: a case report.

A 72-year-old Japanese woman was treated by 3000 mg/day of valacyclovir for the herpes zoster in her left back. She had been treated as hypertension with no renal insufficiency. In two days, she visited an emergency room of a regional stroke care center with dysarthria, dexterity disorder and gait disturbance. Neither head CT nor MRI found intracranial lesions, then, laboratory tests revealed that her serum creatinine level was 4.63 mg/dL. She was transferred and admitted to our hospital on the following day and received hemodialysis under the diagnosis of AKI due to acyclovir accompanied with encephalopathy. Afterward, her serum concentration of acyclovir revealed as 44 µg/mL, which is extremely high. Her neurological symptom disappeared in parallel with the decrease of serum concentration of acyclovir. She received 3 sessions of hemodialysis and discharged on the 8th day of admission with almost normal renal function and no neurological sequela.

Hypoxia-inducible Factor-1α Suppresses the Innate Immune Response in Cultured Human Proximal Tubular Cells.

BACKGROUND/AIM: Retinoic acid-inducible gene (RIG)-I like receptors (RLRs) are expressed on renal proximal tubular epithelial cells (RPTECs) in viral nephropathy, indicating the presence of RLR-mediated innate immune responses in RPTECs. Hypoxia is also known to affect innate immunity. This study investigated the effects of hypoxia, and hypoxia-inducible factor (HIF) on innate immunity in RPTECs. MATERIALS AND METHODS: Primary human RPTECs were cultured under normoxic or hypoxic conditions and treated with a synthetic analog of double-stranded RNA (polyIC). The expression levels of RIG-I and MDA5, as RLRs, and IFNß, IL6, and TNFα, as inflammatory mediators were evaluated using quantitative reverse transcription-polymerase chain reaction, western blotting, and lactate dehydrogenase activity (LDH) assays. To further investigate the role of hypoxia, a small interfering RNA was used to knockdown HIF1α. RESULTS: Under normoxic conditions, polyIC increased RIG-I, MDA5, and IFNß mRNA expression in RPTECs by, 9.4±0.4-, 10.8±0.5-, and 4.0±0.1-fold, respectively, compared to control, and by 5.4±0.1-, 7.4±0.1-, and 2.4±0.3-fold, respectively, under hypoxic conditions, the rate of increase was lower than that under normoxic conditions (p<0.01). Protein expression showed a similar trend. Under hypoxic conditions, polyIC treatment with HIF1α knockdown in RPTECs increased RIG-I, MDA5, and IFNß mRNA expression by 3.1±0.5-, 2.9±0.4-, and 6.1±0.4-fold, respectively, and cytotoxicity, demonstrated by LDH assay, was increased compared to that without knockdown (all p<0.01). CONCLUSION: Hypoxia suppresses polyIC-induced RLRs mediated innate immune responses in RPTECs via HIF1α.

Dietary Intake of Polyunsaturated Fatty Acids and Diabetic Nephropathy: Cohort Analysis of the Tsugaru Study.

BACKGROUND/AIM: Diabetic nephropathy (DN) is the leading cause of end-stage renal failure and its incidence continues to increase. To decrease this, a countermeasure from an early stage is required. This is a DN stage 2 observation study that analyzed the results of a concurrent dietary survey in the Tsugaru study and discussed the relationship between dietary intake of n-3 fatty acid and DN. PATIENTS AND METHODS: Patients with stage 2 DN and aged 20 years or older in the Tsugaru region of Aomori Prefecture were enrolled. We examined the association between urinary albumin excretion (UAE) at enrollment and 36 months later and n-3PUFA intake obtained from a dietary survey. RESULTS: Of the 317 subjects at enrollment, 234 were followed for 36 months, of whom 123 were able to complete the dietary survey. After 36 months of follow-up of these 123 subjects, 28 were in remission and 18 had progressed. Correlations between UAE at 36 months and each of the parameters were examined and UAE at enrollment showed a positive correlation (r=0.4224, p<0.001); correlations between eicosapentaenoic acid (EPA)/arachidonic acid (AA), EPA+docosahexaenoic acid/AA, and n-6/n-3 and UAE at 36 months were weak. As shown by multiple regression analysis, the factor influencing UAE after 36 months was UAE at enrollment. CONCLUSION: Concerning the relationship between fatty acid intake balance and UAE, the previously reported renoprotective effect of n-3 fatty acids could not be demonstrated.

Humoral response to SARS-CoV-2 mRNA vaccine on in ABO blood type incompatible kidney transplant recipients treated with low-dose rituximab.

We aimed to evaluate the humoral response after the second and third doses of SARS-CoV-2 mRNA vaccine in ABO blood type incompatible kidney transplant (KT) recipients treated with rituximab. This retrospective study conducted between June 2021 and June 2022 included 131 KT recipients and 154 nontransplant controls who had received mRNA vaccines. We compared the seropositivity (anti-SARS-CoV-2 spike IgG antibody titer ≥ 0.8 U/mL) after the second and third vaccinations. Furthermore, we evaluated the impact of pretransplant vaccination for seropositivity. Of the 131 KT recipients, 50 had received the third dose of mRNA vaccine. The antibody titer was significantly increased after the third dose of mRNA vaccine. The seropositivity rate after the third dose of mRNA vaccine increased from 36 to 70%. We observed no significant difference in seropositivity after the third dose of mRNA vaccine in ABO incompatibility, rituximab use, mycophenolate mofetil use, and age at KT. Of the nine recipients who had received the second or third dose of the mRNA vaccine prior to the KT, eight of the recipients were seropositive both before and after the KT. Our results suggest that ABO incompatibility or rituximab use was not significantly associated with seropositivity.

Impact of timing of rejection episode on cardiovascular events in living donor kidney transplantation: a multicenter retrospective study.

BACKGROUND: Cardiovascular diseases are still highly prevalent after kidney transplantation. However, little is known about the impact of the timing of rejection episodes on cardiovascular disease. The study aimed to analyze the influence of the timing of rejection episodes on cardiovascular events in recipients of living donor kidney transplantation. METHODS: We studied 572 living donor kidney transplant recipients from the Michinoku Renal Transplant Network (MRTN), which includes 6 centers in the Tohoku region of Japan. Fine-Gray proportional hazards regression analysis with time-dependent variables was used to assess the effect of rejection episode on cardiovascular events. Recipients were divided into three groups: those without rejection (non-rejection, 370 patients), rejection within 6 months after transplantation (early rejection, 99 patients), and rejection after 6 months (late rejection, 103 patients). The effect of timing on cardiovascular events was evaluated using Fine-Gray proportional hazards regression analysis. RESULTS: During a median follow-up of 77 months, 70 patients experienced cardiovascular events. Rejection episodes were significantly associated with cardiovascular events (hazard ratio [HR]: 2.08, 95% confidence interval [CI]: 1.26-3.43, P = 0.004), along with age and dialysis vintage. The 5-year cumulative incidence of cardiovascular events was significantly higher in the late rejection group than in the early rejection group (15% vs. 3.3%, P = 0.021). However, no significant difference in 5-year cumulative cardiovascular event incidence was observed between the early rejection and non-rejection groups. Late rejection was significantly associated with cardiovascular events (HR: 2.40, 95% CI: 1.38-4.18, P = 0.002), whereas early rejection was not significantly correlated with cardiovascular event risk (HR: 1.18, P = 0.670). CONCLUSIONS: Rejections occurring more than 6 months after transplantation is significantly associated with risk of cardiovascular events. TRIAL REGISTRATION NUMBER: 2019-099-1, date of registration; 3 Dec. 2019, retrospectively registered.

Relationship Between Cardiovascular Events and Serum Lipid and Plasma Fatty Acid Profile in Maintenance Hemodialysis Patients With Diabetic Mellitus.

BACKGROUND/AIM: Cardiovascular disease (CVD) is a frequent complication in hemodialysis (HD) patients, especially when the underlying disease is diabetes mellitus (DM). In this study, we investigated cardiovascular events and lipid and fatty acid profile in maintenance HD patients with diabetic kidney disease (DKD). PATIENTS AND METHODS: The subjects were 123 patients undergoing HD at Oyokyo Kidney Research Institute Hirosaki Hospital, who were considered to have DKD as the underlying cause of dialysis induction. Among these patients, the lipid and fatty acid profile were examined in two groups, CVD group (n=53) and non-CVD group (n=70), according to the presence or absence of a history of cardiovascular events (coronary artery disease, stroke, arteriosclerosis obliterans, valvular disease, and aortic disease). For serum lipid profile, the levels of total-cholesterol (T-C), triglycerides (TG), high density lipoprotein-cholesterol (HDL-C), and low density lipoprotein-cholesterol (LDL-C) were measured, and for fatty acid balance, 24 fractions of fatty acid composition in plasma total lipids were measured. These markers were compared between the CVD and non-CVD groups. RESULTS: The levels of T-C and TG were significantly lower in the CVD group compared with the non-CVD group (147.7±36.9 mg/dl vs. 159.2±35.6 mg/dl, p<0.05, 120.2±65.7 mg/dl vs. 143.8±124.4 mg/dl, p<0.05). In the plasma fatty acid composition, alpha-linolenic acid (ALA) and docosapentaenoic acid (DPA) were significantly lower in the CVD group compared with the non-CVD group (0.74±0.26 wt% vs. 0.84±0.31 wt%, p<0.05; 0.61±0.21 wt% vs. 0.70±0.30 wt%, p<0.05). CONCLUSION: Abnormal fatty acid balance, especially low levels of ALA and DPA, rather than serum lipids, are more likely the factors associated with cardiovascular events in maintenance HD patients with underlying DKD.

Mizoribine suppresses proliferation of rat glomerular epithelial cells in culture and inhibits increase of monocyte chemoattractant protein-1 and macrophage inflammatory protein-2 stimulated by thrombin.

Glomerular crescents play an important role in progressive glomerular injury. The lesions consist of epithelial cells, macrophages and fibrin deposition. Macrophage chemoattractant protin-1 (MCP-1) is a chemoattractant of monocytes, which has a potential of procoagulant activity. Macrophage inflammatory protein-2 (MIP-2) is a chemoattractant of neutrophils and acute necrotizing injury is primarily mediated by neutrophils in crescentic glomerulonephritis. Mizoribine (MZR) is an immunosuppressive drug and it has been used for organ transplantation and treatment of various autoimmune diseases. The aim of this study is to investigate the effects of MZR on glomerular epithelial cells (GEC). Rat GEC were cultured with K1 medium and used from 12th to 14th passage. GEC proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. MCP-1 and MIP-2 were quantified by enzyme-linked immunosorbent assay (ELISA) in culture supernatants and mRNA expressions of MCP-1 and MIP-2 were analyzed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). The proliferation of GEC was suppressed by MZR in a dose-dependent manner in the range of 1.0-100.0 µg/mL. These concentrations of MZR had no toxic effect to GEC. Thrombin (1.0-5.0 U/mL) enhanced the production of MCP-1, MIP-2 and the mRNA expressions of MCP-1 and MIP-2. The stimulatory effect of thrombin was inhibited by addition of MZR (10 µg/mL). It is concluded that MZR may be useful for the treatment of crescentic glomerulonephritis.

Kidney Transplantation in a Patient With Noonan Syndrome: A Case Report.

Noonan syndrome (NS) is a congenital genetic abnormality characterized by short stature, delayed onset of puberty, cardiac malformations, and characteristic external malformations. Congenital chromosomal or genetic abnormalities are sometimes associated with carcinomas. Furthermore, they are difficult to manage perioperatively because of multiple complications and mental retardation. The safety of kidney transplantation for patients with NS has not been established. We are reporting the case of a 31-year-old man with NS who received a kidney transplantation after a donor's brain death. He received kidney transplantation safely and was discharged without issues. Kidney transplantation for patients with congenital chromosomal or genetic abnormalities is feasible without serious complications, with a regular follow-up, and psychological support from patients and families.

Seroprevalence of SARS-CoV-2 spike IgG antibodies after the second BNT162b2 mRNA vaccine in Japanese kidney transplant recipients.

We aimed to evaluate the seroprevalence and investigated factors associated with seropositivity after the second SARS-CoV-2 mRNA vaccination in kidney transplant (KT) recipients. This retrospective study conducted between June and November 2021 included 106 KT recipients and 127 healthy controls who received the second dose of the BNT162b2 mRNA vaccine at least 7 days before the measurement of antibody titers. The antibody titer against the receptor-binding domain of SARS-CoV-2 spike (S) protein was determined. We compared seroprevalence rates (immunoglobulin G [IgG] level of ≥ 0.8 or ≥ 15 U/mL) between the healthy controls and KT recipients and identified factors associated with impaired humoral response. The seroprevalence rate of the healthy controls and KT recipients was 98% and 22%, respectively. Univariate logistic regression analysis revealed that age > 53 years, rituximab use, mycophenolate mofetil use, and KT vintage < 7 years were negatively associated with the rate of anti-SARS-CoV-2 S IgG ≥ 15 U/mL in KT recipients. ABO blood type incompatible KT was not significantly associated with seroprevalence. Humoral response after the second BNT162b2 mRNA vaccine was greatly hindered by immunosuppression therapy in KT recipients. Older age, rituximab use, mycophenolate mofetil use, and KT vintage may play key roles in seroconversion.

p122 protein enhances intracellular calcium increase to acetylcholine: its possible role in the pathogenesis of coronary spastic angina.

OBJECTIVE: Phospholipase C-δ1 activity is enhanced in patients with coronary artery spasm, and a p122 protein was recently cloned to potentiate phospholipase C-δ1 activity. To investigate the role of p122 in enhanced vasomotility, we examined p122 expression in the cultured skin fibroblasts obtained from patients with and without coronary spasm, intracellular Ca(2+) concentration ([Ca(2+)]i) [corrected] at baseline and after stimulation with acetylcholine in the cells transfected with p122, and promoter in genomic DNA. METHODS AND RESULTS: [corrected] p122 protein and gene expression levels in patients with coronary spasm (n=11) were enhanced compared with levels in control subjects (n=9) (P<0.01 for both). [Ca(2+)](i) at baseline and the peak increase in [Ca(2+)](i) in response to acetylcholine were both 2 times higher in cells transfected with p122 than in those without p122. Conversely, knockdown of p122 resulted in diminished [Ca(2+)](i) response. In the p122 promoter analysis, the -228G/A and -1466C/T variants revealed the increase in luciferase activity. Although the -1466C/T variant was similar between 144 patients with coronary spasm and 148 controls, the -228G/A variant was more frequent in male patients than in male controls (P<0.05). CONCLUSIONS: The p122 protein is upregulated in patients with coronary spasm, causing increased [Ca(2+)](i) to acetylcholine, and thereby seems to be related to enhanced coronary vasomotility.

PolyIC Induces Retinoic Acid-inducible Gene-I and Melanoma Differentiation-associated Gene 5 and Modulates Inflammation in Podocytes.

BACKGROUND/AIM: Viral infection often exacerbates proteinuria, which has been suggested to be due to antiviral responses of podocytes. We examined the effect of polyinosinic-polycytidylic acid (polyIC) on the expression of retinoic acid-inducible gene-I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5) in differentiated human podocytes in culture. MATERIALS AND METHODS: The podocytes were treated with 2 ng/ml to 500 µg/ml of polyIC for 3 to 36 h, and also transfected with siRNA against RIG-I and MDA5. F-actin staining was performed to assess actin reorganization. RESULTS: PolyIC induced the expression of RIG-I and MDA5 in dose- and time-dependent manner, accompanied with interferon-ß (IFN-ß) and interleukin-6 (IL-6) up-regulation and actin reorganization. Temporal knockdown of RIG-I by siRNA decreased IFN-ß expression, while MDA5 siRNA inhibited IFN-ß and IL-6 expression. Actin reorganization was attenuated by RIG-I and MDA5 knockdown. CONCLUSION: RIG-I and MDA5 may play a role in the antiviral responses of podocytes.

Nintedanib-Induced Renal Thrombotic Microangiopathy.

Nintedanib is a unique tyrosine kinase inhibitor used to suppress fibrosis in patients with idiopathic pulmonary fibrosis (IPF). Nintedanib has been shown to suppress multiple processes of fibrosis, thereby reducing the rate of lung function decline in patients with IPF. Since vascular endothelial growth factor is one of this agent's targets, nephrotoxicity, including renal thrombotic microangiopathy (TMA), is a possible major adverse effect. However, only 2 previous cases of nintedanib-induced renal TMA have been published. Our patient was an 83-year-old man with IPF. As adverse effects including liver enzyme level elevation, diarrhoea, anorexia, and nephrotoxicity developed, the nintedanib dosage was reduced after 9 months. The digestive symptoms resolved promptly, but the proteinuria and reduced kidney function remained. Although the kidney injury had improved to some extent, we performed a percutaneous renal biopsy. The biopsy revealed typical TMA findings such as microaneurysms filled with pale material, segmental double contours of glomerular basement membranes, and intracapillary foam cells. After discontinuation of nintedanib, the patient's nephrotoxicity improved. Nintedanib-induced renal TMA is reversible and is possibly dose-dependent. Here, we report the clinical course of our case and review the characteristics of nintedanib-induced renal TMA.