Artificial intelligence supported anemia control system (AISACS) to prevent anemia in maintenance hemodialysis patients.

Anemia, for which erythropoiesis-stimulating agents (ESAs) and iron supplements (ISs) are used as preventive measures, presents important difficulties for hemodialysis patients. Nevertheless, the number of physicians able to manage such medications appropriately is not keeping pace with the rapid increase of hemodialysis patients. Moreover, the high cost of ESAs imposes heavy burdens on medical insurance systems. An artificial-intelligence-supported anemia control system (AISACS) trained using administration direction data from experienced physicians has been developed by the authors. For the system, appropriate data selection and rectification techniques play important roles. Decision making related to ESAs poses a multi-class classification problem for which a two-step classification technique is introduced. Several validations have demonstrated that AISACS exhibits high performance with correct classification rates of 72%-87% and clinically appropriate classification rates of 92%-98%.

Successful deceased donor kidney transplantation to a recipient with a history of COVID-19 treatment.

CASE PRESENTATION: A 49-year-old Asian male, who had undergone hemodialysis for >16 years, complained of a fever, dysgeusia and dysosmia, and was diagnosed with COVID-19 pneumonia based on severe acute respiratory syndrome coronavirus 2 polymerase chain reaction (SARS-CoV-2 PCR) and computed tomography (CT). Treatment was started with oral favipiravir and ciclesonide inhalation. On the 10th day of treatment, the patient had a persistent high fever and a chest CT showed exacerbation of pneumonia, so dexamethasone was intravenously started. He was discharged after confirming two consecutive negative SARS-CoV-2 PCR tests. Three months after COVID-19 treatment, a SARS-CoV-2 PCR test was negative and he underwent a deceased donor kidney transplantation. Basiliximab induction with triple drug immunosuppression consisting of extended-release tacrolimus, mycophenolate mofetil and prednisolone, which is our regular immunosuppression protocol, was used. He was discharged on postoperative day 18 without the need for postoperative hemodialysis or any complications. The serum creatinine level was 1.72 mg/dL 95 days postoperatively and he had a favorable clinical course that was similar to deceased donor kidney recipients without a history of SARS-CoV-2 infection. CONCLUSION: We report the first case of a kidney transplantation after COVID-19 treatment in Japan and the fourth case globally. We would like to provide information about our successful case due to the anticipated increase in similar candidates in the near future.

High expression of a vascular stricture-related marker is predictive of an early response to tolvaptan, and a low fractional excretion of sodium is predictive of a poor long-term survival after tolvaptan administration for liver cirrhosis.

AIM: Tolvaptan is a newly available diuretic that has a specific function in water reabsorption inhibition. Given that spironolactone or furosemide induces the aggravation of cirrhotic hyponatremia and dehydration, tolvaptan affects the management strategy of liver cirrhosis. Representative predictive markers of its response include renal function-related markers such as urea nitrogen or creatinine. However, vascular function-related markers have not been well investigated. We investigated the effect of the vascular function-related marker asymmetric dimethylarginine (ADMA) and the effective arterial blood volume (EABV) marker, fractional excretion of sodium (FENa), on the early tolvaptan response and survival in liver cirrhosis. METHODS: We prospectively recruited 49 patients who required add-on tolvaptan for refractory ascites or edema. Laboratory data were obtained immediately before and 1 day after tolvaptan administration. Patients exhibiting >1.5 kg weight loss after 1 week were categorized as early responders to tolvaptan. Patients were followed for a median of 200 days and were assessed for survival. RESULTS: Early responders showed lower creatinine levels (<1.0 mg/dL), and higher ADMA levels (≥0.61 nmol/mL) than others in a multivariate analysis. Patients with a shorter survival were positive for hepatocellular carcinoma and had a low FENa (<0.35%). CONCLUSION: Early responders showed higher ADMA levels reflecting vascular stricture, suggesting that higher vascular tonus is required for a tolvaptan early response. Patients with a shorter survival showed a lower FENa, reflecting a lower EABV and suggesting that adequate EABV is required for the prolonged survival after tolvaptan administration.

The urinary levels of prostanoid metabolites predict acute kidney injury in heterogeneous adult Japanese ICU patients: a prospective observational study.

BACKGROUND: Acute kidney injury (AKI) is frequently observed in critically ill patients in the intensive care unit (ICU) and is associated with increased mortality. Prostanoids regulate numerous biological functions, including hemodynamics and renal tubular transport. We herein investigated the ability of urinary prostanoid metabolites to predict the onset of AKI in critically ill adult patients. METHODS: The current study was conducted as a prospective observational study. Urine of patients admitted to the ICU at Okayama University Hospital was collected and the urinary levels of prostaglandin E2 (PGE2), PGI2 metabolite (2,3-dinor-6-OXO-PGF1α), thromboxane A2 (TXA2) metabolite (11-dehydro-TXB2) were determined. RESULTS: Of the 93 patients, 24 developed AKI (AKIN criteria). Surgical intervention (93, 75 %) was the leading cause of ICU admission. Overall, the ratio of the level of serum Cr on Day 1 after ICU admission to that observed at baseline positively correlated with the urinary 2,3-dinor-6-OXO-PGF1α/Cr (r = 0.57, p < 0.0001) and 11-dehydro-TXB2/Cr (r = 0.47, p < 0.0001) ratios. In 16 cases of de novo AKI, the urinary 2,3-dinor-6-OXO-PGF1α/Cr and 11-dehydro-TXB2/Cr values were significantly elevated compared with that observed in the non-AKI group, whereas the urinary PGE2/Cr values were not. The urinary 2,3-dinor-6-OXO-PGF1α/Cr ratio exhibited the best diagnostic and predictive performance among the prostanoid metabolites according to the receiver operating characteristic (ROC) analysis [ROC-area under the curve (AUC): 0.75]. CONCLUSIONS: Taken together, these results demonstrate that the urinary 2,3-dinor-6-OXO-PGF1α/Cr and 11-dehydro-TXB2/Cr ratios are associated with the subsequent onset of AKI and poor outcomes in adult heterogeneous ICU patients.

Acoustic radiation force impulse elastography of the kidneys: is shear wave velocity affected by tissue fibrosis or renal blood flow?

OBJECTIVES: The aim of this study was to identify the main influencing factor of the shear wave velocity (SWV) of the kidneys measured by acoustic radiation force impulse elastography. METHODS: The SWV was measured in the kidneys of 14 healthy volunteers and 319 patients with chronic kidney disease. The estimated glomerular filtration rate was calculated by the serum creatinine concentration and age. As an indicator of arteriosclerosis of large vessels, the brachial-ankle pulse wave velocity was measured in 183 patients. RESULTS: Compared to the degree of interobserver and intraobserver deviation, a large variance of SWV values was observed in the kidneys of the patients with chronic kidney disease. Shear wave velocity values in the right and left kidneys of each patient correlated well, with high correlation coefficients (r = 0.580-0.732). The SWV decreased concurrently with a decline in the estimated glomerular filtration rate. A low SWV was obtained in patients with a high brachial-ankle pulse wave velocity. Despite progression of renal fibrosis in the advanced stages of chronic kidney disease, these results were in contrast to findings for chronic liver disease, in which progression of hepatic fibrosis results in an increase in the SWV. Considering that a high brachial-ankle pulse wave velocity represents the progression of arteriosclerosis in the large vessels, the reduction of elasticity succeeding diminution of blood flow was suspected to be the main influencing factor of the SWV in the kidneys. CONCLUSIONS: This study indicates that diminution of blood flow may affect SWV values in the kidneys more than the progression of tissue fibrosis. Future studies for reducing data variance are needed for effective use of acoustic radiation force impulse elastography in patients with chronic kidney disease.

Renal distribution of Vasohibin-1 in patients with chronic kidney disease.

Experimental studies have demonstrated the involvement of angiogenesis-related factors in the progression of chronic kidney disease (CKD). There have so far been no reports investigating the distribution and clinical roles of Vasohibin-1 (VASH-1), a negative feedback regulator of angiogenesis, in CKD. We recruited 54 Japanese CKD patients and 6 patients who had normal renal tissues excised due to localized renal cell carcinoma. We evaluated the correlations between the renal expression level of VASH-1 and the clinical/histological parameters. VASH-1 was observed in renal endothelial/mesangial cells, crescentic lesions and interstitial inflammatory cells. Significant positive correlations were observed between 1) crescent formation and the number of VASH-1+ cells in the glomerulus (r＝0.48, p＝0.001) or cortex (r＝0.64, p＜0.0001), 2) interstitial cell infiltration and the number of VASH-1+ cells in the cortex (r＝0.34, p＝0.02), 3) the glomerular VEGFR-2+ area and the number of VASH-1+ cells in the glomerulus (r＝0.44, p＝0.01) or medulla (r＝0.63, p＝0.01). These results suggest that the renal levels of VASH-1 may be affected by local inflammation, crescentic lesions and VEGFR-2.

A Case of Drug-Resistant Myoclonus Improved by Only Slight Adjustment to the Hemodialysis Setting.

Myoclonus, a rare complication in patients with end-stage renal disease, is typically ameliorated through hemodialysis. The present case concerns an 84-year-old male with chronic renal failure undergoing hemodialysis, presenting involuntary movements in his limbs, which gradually worsened from the initiation of hemodialysis without constant elevation of serum blood urea nitrogen and electrolytes levels. Surface electromyography revealed characteristic findings consistent with myoclonus. He was diagnosed with subcortical-nonsegmental myoclonus related to hemodialysis, and the myoclonus was significantly alleviated after slightly increasing the post-dialysis target weight even though drug treatment was ineffective. This case suggests that drug-resistant myoclonus in patients with renal failure may be improved by adjusting hemodialysis settings, even in cases of atypical dialysis disequilibrium syndrome.

The Effect of Medical Cooperation in the CKD Patients: 10-Year Multicenter Cohort Study.

INTRODUCTION: While chronic kidney disease (CKD) is one of the most important contributors to mortality from non-communicable diseases, the number of nephrologists is limited worldwide. Medical cooperation is a system of cooperation between primary care physicians and nephrological institutions, consisting of nephrologists and multidisciplinary care teams. Although it has been reported that multidisciplinary care teams contribute to the prevention of worsening renal functions and cardiovascular events, there are few studies on the effect of a medical cooperation system. METHODS: We aimed to evaluate the effect of medical cooperation on all-cause mortality and renal prognosis in patients with CKD. One hundred and sixty-eight patients who visited the one hundred and sixty-three clinics and seven general hospitals of Okayama city were recruited between December 2009 and September 2016, and one hundred twenty-three patients were classified into a medical cooperation group. The outcome was defined as the incidence of all-cause mortality, or renal composite outcome (end-stage renal disease or 50% eGFR decline). We evaluated the effects on renal composite outcome and pre-ESRD mortality while incorporating the competing risk for the alternate outcome into a Fine-Gray subdistribution hazard model. RESULTS: The medical cooperation group had more patients with glomerulonephritis (35.0% vs. 2.2%) and less nephrosclerosis (35.0% vs. 64.5%) than the primary care group. Throughout the follow-up period of 5.59 ± 2.78 years, 23 participants (13.7%) died, 41 participants (24.4%) reached 50% decline in eGFR, and 37 participants (22.0%) developed end-stage renal disease (ESRD). All-cause mortality was significantly reduced by medical cooperation (sHR 0.297, 95% CI 0.105-0.835, p = 0.021). However, there was a significant association between medical cooperation and CKD progression (sHR 3.069, 95% CI 1.225-7.687, p = 0.017). CONCLUSION: We evaluated mortality and ESRD using a CKD cohort with a long-term observation period and concluded that medical cooperation might be expected to influence the quality of medical care in the patients with CKD.

Sustained-release prostacyclin analog ONO-1301 ameliorates tubulointerstitial alterations in a mouse obstructive nephropathy model.

Tubulointerstitial injuries are crucial histological alterations that predict the deterioration of renal function in chronic kidney disease. ONO-1301, a novel sustained-release prostacyclin analog, accompanied by thromboxane synthase activity, exerts therapeutic effects on experimental pulmonary hypertension, lung fibrosis, cardiomyopathy, and myocardial ischemia, partly associated with the induction of hepatocyte growth factor (HGF). In the present study, we examined the therapeutic efficacies of ONO-1301 on tubulointerstitial alterations induced by unilateral ureteral obstruction (UUO). After inducing unilateral ureteral obstruction in C57/BL6J mice, a single injection of sustained-release ONO-1301 polymerized with poly (D,L-lactic-co-glycolic acid) sustained-release ONO-1301 (SR-ONO) significantly suppressed interstitial fibrosis, accumulation of types I and III collagen, increase in the number of interstitial fibroblast-specific protein-1 (FSP-1)(+) cells, and interstitial infiltration of monocytes/macrophages (F4/80(+)) in the obstructed kidneys (OBK; day 7). Treatment with SR-ONO significantly suppressed the increase of the renal levels of profibrotic factor TGF-ß and phosphorylation of Smad2/3, and elevated the renal levels of HGF in the OBK. In cultured mouse proximal tubular epithelial cells (mProx24), ONO-1301 significantly ameliorated the expression of fibroblast-specific protein-1 and α-smooth muscle actin as well as phosphorylation of Smad3 and increased the expression of zonula occludens-1 and E-cadherin in the presence of TGF-ß1 as detected by immunoblot and immunocytochemistry, partly dependent on PGI(2) receptor-mediated signaling. Administration of rabbit anti-HGF antibodies, but not the control IgG, partly reversed the suppressive effects of SR-ONO on tubulointerstitial injuries in the OBK. Taken together, our findings suggest the potential therapeutic efficacies of ONO-1301 in suppressing tubulointerstitial alterations partly mediated via inducing HGF, an antifibrotic factor counteracting TGF-ß.

Silica-associated systemic lupus erythematosus with lupus nephritis and lupus pneumonitis: A case report and a systematic review of the literature.

INTRODUCTION: Several epidemiological studies have shown that silica exposure triggers the onset of systemic lupus erythematosus (SLE); however, the clinical characteristics of silica-associated SLE have not been well studied. PATIENT CONCERNS: A 67-year-old man with silicosis visited a primary hospital because of a fever and cough. His respiratory condition worsened, regardless of antibiotic medication, and he was referred to our hospital. DIAGNOSIS: The patient showed leukopenia, lymphopenia, serum creatinine elevation with proteinuria and hematuria, decreased serum C3 level, and was positive for anti-double stranded DNA antibody, anti-nuclear antibody, and direct Coombs test. He was diagnosed with SLE. Renal biopsy was performed, and the patient was diagnosed with lupus nephritis (class IV-G(A/C) + V defined by the International Society of Nephrology/Renal Pathology Society classification). Computed tomography revealed acute interstitial pneumonitis, bronchoalveolar lavage fluid showed elevation of the lymphocyte fraction, and he was diagnosed with lupus pneumonitis. INTERVENTIONS: Prednisolone (50 mg/day) with intravenous cyclophosphamide (500 mg/body) were initiated. OUTCOMES: The patient showed a favorable response to these therapies. He was discharged from our hospital and received outpatient care with prednisolone slowly tapered off. He had cytomegalovirus and herpes zoster virus infections during treatment, which healed with antiviral therapy. REVIEW: We searched for the literature on sSLE, and selected 11 case reports and 2 population-based studies. The prevalence of SLE manifestations in sSLE patients were comparative to that of general SLE, particularly that of elderly-onset SLE. Our renal biopsy report and previous reports indicate that lupus nephritis of sSLE patients show as various histological patterns as those of general SLE patients. Among the twenty sSLE patients reported in the case articles, three patients developed lupus pneumonitis and two of them died of it. Moreover, two patients died of bacterial pneumonia, one developed aspergillus abscesses, one got pulmonary tuberculosis, and one developed lung cancer. CONCLUSION: Close attention is needed, particularly for respiratory system events and infectious diseases, when treating patients with silica-associated SLE using immunosuppressive therapies.

Acute Kidney Injury Caused by Evans Syndrome with Systemic Lupus Erythematosus and Systemic Sclerosis.

A 65-year-old woman with systemic sclerosis and systemic lupus erythematosus developed acute kidney injury (AKI), Coombs-positive autoimmune hemolytic anemia and autoimmune thrombocytopenia; therefore, she was diagnosed with Evans syndrome (ES). Intravascular hemolysis was suggested as the cause of AKI based on the presence of acute tubular injury and trace hemosiderin deposits on the renal biopsy. The renal function, hemolytic anemia and thrombocytopenia were restored by an increased dose of glucocorticoids, hemodialysis, and plasma exchange. Although ES with severe hemolytic anemia is very rare, it is important to detect possible renal dysfunction when encountering patients with severe hemolysis.

Podocyte autophagy is associated with foot process effacement and proteinuria in patients with minimal change nephrotic syndrome.

Autophagy is a cellular mechanism involved in the bulk degradation of proteins and turnover of organelle. Several studies have shown the significance of autophagy of the renal tubular epithelium in rodent models of tubulointerstitial disorder. However, the role of autophagy in the regulation of human glomerular diseases is largely unknown. The current study aimed to demonstrate morphological evidence of autophagy and its association with the ultrastructural changes of podocytes and clinical data in patients with idiopathic nephrotic syndrome, a disease in which patients exhibit podocyte injury. The study population included 95 patients, including patients with glomerular disease (minimal change nephrotic syndrome [MCNS], n = 41; idiopathic membranous nephropathy [IMN], n = 37) and 17 control subjects who underwent percutaneous renal biopsy. The number of autophagic vacuoles and the grade of foot process effacement (FPE) in podocytes were examined by electron microscopy (EM). The relationships among the expression of autophagic vacuoles, the grade of FPE, and the clinical data were determined. Autophagic vacuoles were mainly detected in podocytes by EM. The microtubule-associated protein 1 light chain 3 (LC3)-positive area was co-localized with the Wilms tumor 1 (WT1)-positive area on immunofluorescence microscopy, which suggested that autophagy occurred in the podocytes of patients with MCNS. The number of autophagic vacuoles in the podocytes was significantly correlated with the podocyte FPE score (r = -0.443, p = 0.004), the amount of proteinuria (r = 0.334, p = 0.033), and the level of serum albumin (r = -0.317, p = 0.043) in patients with MCNS. The FPE score was a significant determinant for autophagy after adjusting for the age in a multiple regression analysis in MCNS patients (p = 0.0456). However, such correlations were not observed in patients with IMN or in control subjects. In conclusion, the results indicated that the autophagy of podocytes is associated with FPE and severe proteinuria in patients with MCNS. The mechanisms underlying the activation of autophagy in association with FPE in podocytes should be further investigated in order to elucidate the pathophysiology of MCNS.

A case of immunotactoid glomerulopathy exhibiting nephrotic syndrome successfully treated with corticosteroids and antihypertensive therapy.

We report a case of immunotactoid glomerulopathy (ITG) with cerebral hemorrhage and hypocomplementemia, with successful therapeutic outcome following the corticosteroids and antihypertensive treatment. A 70-year-old man presented with facial edema in October 2006. One day prior to his referral, he experienced speech disturbance, headache, and vomiting, and on the next day he was referred to our hospital. The laboratory examination revealed massive proteinuria (11.3 g/day) and hematuria. The total serum hemolytic complement (CH50) was decreased to 23 U/ml and C4 component was decreased to 7.5 mg/dl, whereas C3 component remained within normal limits (82 mg/dl). Brain computed tomography scan showed high-density lesions in the left parieto-occipital area suggesting subcortical cerebral hemorrhage. Renal biopsy revealed diffuse subendothelial PAS-positive depositions. Immunofluorescence studies revealed intensive deposition of IgG, IgA, C3, C1q, Fibrinogen, and kappa light chain with granular pattern in the capillary and mesangial area. Electron microscopic examination revealed regularly arranged microtubular deposits, appearing as 21-33 nm in diameter. Based on these findings, this patient was diagnosed as ITG complicated with cerebral hemorrhage and hypocomplementemia. He received oral prednisolone (30 mg/day), resulting in reduction of proteinuria, improvement of hypocomplementemia, and prevention of renal functional deterioration. This case demonstrates that accurate diagnosis of ITG may result in successful therapeutic outcome.

A case of fatal osteolytic hypercalcemia complicated with IgG4-related ophthalmic disease leading to renal failure.

A 40-year-old male was hospitalized with renal impairment and severe hypercalcemia. His concentration of serum IgG4 was high, but serum whole PTH, 1-25(OH)2 vitamin D3 and PTHrP were not elevated. Computed tomography showed swelling of the bilateral lacrimal glands and systemic lymphadenopathy. The histological findings of lacrimal gland biopsy fulfilled the diagnostic criteria of IgG4-related ophthalmic disease (IgG4ROD). Bone scintigraphy showed increased ectopic uptake in the stomach, heart, lungs, and kidneys. He died on day 16 of admission, although the therapies for hypercalcemia were continued. Autopsy results showed an increase of osteoclasts in the bone marrow and metastatic calcification in multiple organs, and excluded from the differential diagnosis other disorders which present lymph-node swelling and hypercalcemia such as cancer, lymphoma, Castleman's disease, and sarcoidosis. He was given a diagnosis of IgG4ROD with osteolytic hypercalcemia.

HIV-associated Immune Complex Kidney Disease with C3-dominant Deposition Induced by HIV Infection after Treatment of IgA Nephropathy.

A 57-year-old man was diagnosed with IgA nephropathy. Hematuria and proteinuria were improved by tonsillectomy plus methylprednisolone pulse therapy. Lymphadenopathy, hypocomplementemia and pancytopenia were observed six years later, and urinalysis abnormalities recurred. A biopsy revealed mesangial proliferative glomerulonephritis with C3-dominant deposition. Human immunodeficiency virus (HIV) antibody demonstrated positive conversion. He was diagnosed with HIV-associated immune complex kidney disease (HIVICK). The hematuria, proteinuria and hypocomplementemia were improved by reducing the HIV viral load through antiretroviral therapy. When C3-dominant deposition is observed on a renal biopsy, HIVICK must be differentiated.

Urine 5MedC, a Marker of DNA Methylation, in the Progression of Chronic Kidney Disease.

BACKGROUND: Alterations in DNA methylation may be involved in disease progression in patients with chronic kidney disease (CKD). Recent studies have suggested that 5-methyl-2'-deoxycytidine (5MedC) may be a marker of hypermethylation of DNA. Currently, there is no information available regarding the urine levels of 5MedC and its association with the progression of CKD. METHOD: We examined the urine levels of 5MedC in spot urine samples from 308 patients with CKD (median age: 56 years, male: 53.2%, and glomerulonephritis: 51.0%) using a competitive enzyme-linked immunosorbent assay and investigated the relationships among urine 5MedC, urine albumin, urine α1-microglobulin (α1MG), and the laboratory parameters associated with CKD. The patients were followed for three years to evaluate renal endpoints in a prospective manner. RESULTS: The urine 5MedC level was significantly increased in the later stages of CKD compared to the early to middle stages of CKD. In multiple logistic regression models, urine 5MedC was significantly associated with the prediction of later CKD stages. Urine 5MedC (median value, 65.9 µmol/gCr) was significantly able to predict a 30% decline in the estimated GFR or a development of end-stage renal disease when combined with macroalbuminuria or an increased level of urine α1MG (median value, 5.7 mg/gCr). CONCLUSION: The present data demonstrate that the urine 5MedC level is associated with a reduced renal function and can serve as a novel and potent biomarker for predicting the renal outcome in CKD patients. Further studies will be necessary to elucidate the role of urine DNA methylation in the progression of CKD.

Combination of Renal Angioplasty and Angiotensin-converting-enzyme Inhibitor Can Reduce Proteinuria in Patients with Bilateral Renal Artery Disease.

Recent large clinical trials failed to show clear benefits of percutaneous transluminal renal angioplasty (PTRA) as compared with medical therapy on patients with renal artery stenosis. It was also reported that proteinuria is an adverse prognostic factor after PTRA, and PTRA is less effective in patients with overt proteinuria. From the renoprotective point of view, to reduce proteinuria after PTRA is an important therapeutic goal in patients with renal artery stenosis with overt proteinuria. We hereby describe two patients successfully treated by combination therapy with PTRA and administration of angiotensin-converting enzyme (ACE) inhibitor for bilateral renal artery disease with overt proteinuria.

Amelioration of cisplatin-induced acute renal injury by renal progenitor-like cells derived from the adult rat kidney.

The replacement of a necrotic tubular epithelium with functional tubular epithelial cells is required for recovery from acute renal failure (ARF). A rat renal progenitor-like (rKS56) cell line was recently established derived from the S3 segment of renal proximal tubules. The therapeutic efficacy of rKS56 cells was examined in a rat model of cisplatin-induced ARF. rKS56-lacZ cells expressing 3-galactosidase were injected into SD rats either at the subcapsule of the left kidney (rKS-SC) or via the left renal artery (rKS-IA) 2 days after the injection of cisplatin. Bluo-gal(+) rKS56-lacZ cells were observed in the subcapsule in the rKS-SC group on day 5, and were further increased in number on day 9, accompanied by partial distribution in the corticomedullary junction, but not in the rKS-IA group. A portion of Bluo-gal(+) cells coexpressed Ki-67, aquaporin-1, hepatocyte growth factor (HGF), and c-Met. rKS-SC treatment significantly improved the tubular injury scores, ameliorated tubular cell apoptosis, and induced cell proliferation. The renal function also significantly improved in the rKS-SC group on day 5. These results demonstrate that locally implanted rKS56 cells could differentiate into tubular epithelial cells, thereby accelerating the recovery from tubular injury, most likely by producing tubular trophic factors. These results suggest the therapeutic potential of this novel approach for patients with end-stage renal failure.