The risk factors and clinical outcomes in hepatitis B seropositive and seronegative renal transplant patients.

INTRODUCTION: Hepatitis B virus (HBV) infection is prevalent in Asia including Taiwan. We retrospectively evaluated the risk of HBV reactivation and clinical outcomes in HBV+ and HBV- kidney transplant recipients. METHODS: Patients who underwent kidney transplantation between January 2004 and December 2021 were reviewed. The outcomes of interest included risks of HBV reactivation and patient/graft survival. RESULTS: We identified 337 patients (47.5 ± 12 years) were enrolled in our final cohort. Fifty-two (15.4%) had HBsAg positive at the time of transplantation. Seventeen developed viral reactivations, with 41.2% of them accompanied by active hepatitis. The graft survival, acute rejection rate, and cancer development after kidney transplantation did not differ in terms of HBsAg status. The Cox multivariate analysis indicated the HBV reactivation risk was increased by a lack of pre-transplant anti-HBV medication [hazard ratio (HR), 5.95; 95% confidence interval (CI), 1.31-27.02; P = 0.021 or an absence of lifelong antiviral therapy [HR, 3.14; 95% CI, 1.01-9.74; P = 0.047] Conclusion: Individuals, independent of HBsAg status, had similar prognosis in terms of patient and graft survival, acute rejection rate, and cancer development. The absence of either pre-transplant anti-HBV medication or lifelong antiviral therapy was significantly associated with an increased risk of HBV reactivation.

Molecular Basis for Paradoxical Activities of Polymorphonuclear Neutrophils in Inflammation/Anti-Inflammation, Bactericide/Autoimmunity, Pro-Cancer/Anticancer, and Antiviral Infection/SARS-CoV-II-Induced Immunothrombotic Dysregulation.

Polymorphonuclear neutrophils (PMNs) are the most abundant white blood cells in the circulation. These cells act as the fast and powerful defenders against environmental pathogenic microbes to protect the body. In addition, these innate inflammatory cells can produce a number of cytokines/chemokines/growth factors for actively participating in the immune network and immune homeostasis. Many novel biological functions including mitogen-induced cell-mediated cytotoxicity (MICC) and antibody-dependent cell-mediated cytotoxicity (ADCC), exocytosis of microvesicles (ectosomes and exosomes), trogocytosis (plasma membrane exchange) and release of neutrophil extracellular traps (NETs) have been successively discovered. Furthermore, recent investigations unveiled that PMNs act as a double-edged sword to exhibit paradoxical activities on pro-inflammation/anti-inflammation, antibacteria/autoimmunity, pro-cancer/anticancer, antiviral infection/COVID-19-induced immunothrombotic dysregulation. The NETs released from PMNs are believed to play a pivotal role in these paradoxical activities, especially in the cytokine storm and immunothrombotic dysregulation in the recent SARS-CoV-2 pandemic. In this review, we would like to discuss in detail the molecular basis for these strange activities of PMNs.

Pathogenic Roles of Autoantibodies and Aberrant Epigenetic Regulation of Immune and Connective Tissue Cells in the Tissue Fibrosis of Patients with Systemic Sclerosis.

Systemic sclerosis (SSc) is a multi-system autoimmune disease with tissue fibrosis prominent in the skin and lung. In this review, we briefly describe the autoimmune features (mainly autoantibody production and cytokine profiles) and the potential pathogenic contributors including genetic/epigenetic predisposition, and environmental factors. We look in detail at the cellular and molecular bases underlying tissue-fibrosis which include trans-differentiation of fibroblasts (FBs) to myofibroblasts (MFBs). We also state comprehensively the pro-inflammatory and pro-fibrotic cytokines relevant to MFB trans-differentiation, vasculopathy-associated autoantibodies, and fibrosis-regulating microRNAs in SSc. It is conceivable that tissue fibrosis is mainly mediated by an excessive production of TGF-ß, the master regulator, from the skewed Th2 cells, macrophages, fibroblasts, myofibroblasts, and keratinocytes. After binding with TGF-ß receptors on MFB, the downstream Wnt/ß-catenin triggers canonical Smad 2/3 and non-canonical Smad 4 signaling pathways to transcribe collagen genes. Subsequently, excessive collagen fiber synthesis and accumulation as well as tissue fibrosis ensue. In the later part of this review, we discuss limited data relevant to the role of long non-coding RNAs (lncRNAs) in tissue-fibrosis in SSc. It is expected that these lncRNAs may become the useful biomarkers and therapeutic targets for SSc in the future. The prospective investigations in the development of novel epigenetic modifiers are also suggested.

Efficacy and safety of rituximab in autoimmune and microangiopathic hemolytic anemia: a systematic review and meta-analysis.

BACKGROUND: The efficacy and safety of rituximab (RTX) on hemolytic anemia (HA) is unknown. Therefore we retrospectively analyze the efficacy and safety of RTX in autoimmune hemolytic anemia (AIHA) and microangiopathic hemolytic anemia (MAHA) from the previous literature. METHODS: Data in clinical trials and observational studies were collected from PubMed, Cochrane, Embase, and Google Scholar until Oct 15, 2018. The efficacy and safety of RTX in patients with AIHA or MAHA were assessed and overall response rates (ORRs), complete response rates (CRRs), adverse events (AEs) and relapse rates (RRs) were extracted if available. A meta-analysis was performed with a random-effects model, estimating mean proportions in all studies, and relative rates in comparative studies. RESULTS: After quality assessment, a total of 37 investigations encompassing 1057 patients eligible for meta-analysis were included. Pooled mean proportion of ORR was 0.84 (95% confidence interval [CI] 0.80-0.88), and that of CRR was 0.61 (95% CI 0.49-0.73). Mean AE rate was 0.14 (95% CI 0.10-0.17), and mean RR was 0.21 (95% CI 0.15-0.26). Relative ORR was 1.18 (95% CI 1.02-1.36), and relative CRR was 1.17 (95% CI 0.98-1.39) fold more than the respective non-RTX counter parts. Relative AE rate was 0.77 (95% CI 0.36-1.63), and relative RR was 0.93 (95% CI 0.56-1.55) fold less than the respective non-RTX counter parts. CONCLUSION: RTX is more effective than the treatments without RTX for AIHA and MAHA and is well-tolerated.

Cyclosporine for the treatment of lupus nephritis in patients with systemic lupus erythematosus.

AIMS: This study aimed to assess retrospectively the efficacy and safety of cyclosporin A (CsA) therapy in patients with lupus nephritis (LN). MATERIALS AND METHODS: From September 2005 to August 2015, eligible patients with LN undergoing CsA treatment were enrolled in the study. Medical charts as well as clinical and laboratory data were retrospectively reviewed. The data were evaluated at 0, 1, 6, 12 month(s) after the start of CsA. Serum creatinine (SCr), estimated glomerular filtration rate (eGFR), urine protein/creatinine ratio (uPCR), complement components C3, C4, and anti-double stranded DNA antibody (anti-dsDNA) titers were recorded. Renal response to CsA (complete response (CR) and partial response (PR)) and relapse after stopping CsA were set as primary endpoint, and adverse events, progression to end-stage renal disease (ESRD), and all-cause mortality as secondary endpoint. RESULTS: Among 60 patients enrolled, 11.7%, 20%, 25% achieved CR and 65.0%, 51.7%, 40% achieved PR at 1, 6, and 12 months, respectively. The SCr and eGFR remained stable during follow-up. After 1 year, CsA led to a decrease in median uPCR (3.79 to 0.51, p < 0.001) and anti-dsDNA (10.1 to 5.7 IU/mL, p = 0.011), an increase in mean C3 (75.9 to 88.5 mg/dL, p < 0.001) and C4 (15.9 to 19.5 mg/dL, p < 0.001) as well as a decrease in glucocorticoid dose. There were no deaths or progression to ESRD originating from adverse events in our study. CONCLUSION: CsA is an effective and safe treatment for patients with LN. Further randomized controlled trials are needed.
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Tamm-Horsfall Protein is a Potent Immunomodulatory Molecule and a Disease Biomarker in the Urinary System.

Tamm-Horsfall protein (THP), or uromodulin (UMOD), is an 80-90-kDa phosphatidylinositol-anchored glycoprotein produced exclusively by the renal tubular cells in the thick ascending limb of the loop of Henle. Physiologically, THP is implicated in renal countercurrent gradient formation, sodium homeostasis, blood pressure regulation, and a defense molecule against infections in the urinary system. Investigations have also revealed that THP is an effective binding ligand for serum albumin, immunoglobulin G light chains, complement components C1 and C1q, interleukin (IL)-1ß, IL-6, IL-8, tumor necrosis factor (TNF)-α, and interferon-γ through its carbohydrate side chains for maintaining circulatory and renal immune homeostasis. Thus, THP can be regarded as part of the innate immune system. UMOD mutations play crucial roles in congenital urolithiasis, hereditary hyperuricemia/gout, and medullary cystic kidney diseases. Recent investigations have focused on the immunomodulatory effects of THP on immune cells and on THP as a disease biomarker of acute and chronic kidney diseases. Our studies have suggested that normal urinary THP, through its epidermal growth factor (EGF)-like domains, binds to the surface-expressed EGF-like receptors, cathepsin G, or lactoferrin to enhance polymorphonuclear leukocyte phagocytosis, proinflammatory cytokine production by monocytes/macrophages, and lymphocyte proliferation by activating the Rho family and mitogen-activated protein kinase signaling pathways. Furthermore, our data support both an intact protein core structure and carbohydrate side chains are important for the different protein-binding capacities of THP. Prospectively, parts of the whole THP molecule may be used for anti-TNF-α therapy in inflammatory diseases, autoantibody-depleting therapy in autoimmune disorders, and immune intensification in immunocompromised hosts.

EGF receptor-dependent mechanism may be involved in the Tamm-Horsfall glycoprotein-enhanced PMN phagocytosis via activating Rho family and MAPK signaling pathway.

Our previous studies showed that urinary Tamm-Horsfall glycoprotein (THP) potently enhanced polymorphonuclear neutrophil (PMN) phagocytosis. However, the domain structure(s), signaling pathway and the intracellular events responsible for THP-enhanced PMN phagocytosis remain to be elucidated. THP was purified from normal human urine. The human promyelocytic leukemia cell line HL-60 was induced to differentiate into PMNs by all-trans retinoid acid. Pretreatment with different MAPK and PI3K inhibitors was used to delineate signaling pathways in THP-enhanced PMN phagocytosis. Phosphorylation of molecules responsible for PMN phagocytosis induced by bacterial lipopolysaccharide (LPS), THP, or human recombinant epidermal growth factor (EGF) was evaluated by western blot. A p38 MAPK inhibitor, SB203580, effectively inhibited both spontaneous and LPS- and THP-induced PMN phagocytosis. Both THP and LPS enhanced the expression of the Rho family proteins Cdc42 and Rac that may lead to F-actin re-arrangement. Further studies suggested that THP and EGF enhance PMN and differentiated HL-60 cell phagocytosis in a similar pattern. Furthermore, the EGF receptor inhibitor GW2974 significantly suppressed THP- and EGF-enhanced PMN phagocytosis and p38 and ERK1/2 phosphorylation in differentiated HL-60 cells. We conclude that EGF receptor-dependent signaling may be involved in THP-enhanced PMN phagocytosis by activating Rho family and MAP kinase.

The binding affinity and molecular basis of the structure-binding relationship between urinary Tamm-Horsfall glycoprotein and tumor necrosis factor-α.

In a previous study we noted significant THP binding to TNF-α, but did not explore the molecular basis of the structure-binding relationship. In this study, we used lectin-binding ELISA to assess the carbohydrate compositions of THP, BSA, IgG, TNF-α, and IFN-g. We identified ß(1,4)-N-acetylglucosamine oligomers (GlcNAc) and GlcNAc/branched mannose in BSA, IgG, TNF-α, and THP, but not in IFN-g. These carbohydrate moieties mediated binding with THP. Small amounts of Siaα(2,3)Gal/ GalNAc, Sia(2,6)Gal/GalNAc, and mannose residues were also present in THP and TNF-α. Binding affinity (K(d)) between THP and TNF-α by Scatchard plot analysis was 1.4-1.7 × 10⁻6 M, lower than antigen-antibody or ligand-receptor binding affinities. To elucidate the structure-binding relationship of THP-TNF-α, THP was digested with neuraminidase, ß-galactosidase, O-sialoglycoprotein endopeptidase, carboxypeptidase Y, or proteinase K. ß-galactosidase increased binding capacity of THP for TNF-α. Monosaccharide inhibition suggested that α-methyl-D-mannoside, GlcNAc, and GalNAc, but not sialic acid, suppress THP-TNF-α binding as detected by ELISA. We conclude that sugar-lectin and sugar-protein interactions between cognate sites in THP and TNF-α mediate their binding.

Anti-agalactosyl IgG antibody in ankylosing spondylitis and psoriatic arthritis.

Anti-agalactosyl IgG antibody (anti-Gal(0) IgG) has been regarded as a useful serological marker for rheumatoid arthritis (RA). It is unknown whether it is also elevated in serum and implicated in the pathogenesis of joint inflammation in seronegative spondyloarthropathy (SpA) such as ankylosing spondylitis (AS) and psoriatic arthritis (PsA). Sera were collected from 43 patients with AS or PsA with axial joint involvement, 22 patients with RA, and 25 healthy normal individuals for the detection of anti-Gal(0) IgG with a cup-type lectin enzyme immunoassay (Eitest CA(.)RF). The disease activity of the AS/PsA was evaluated by Bath Ankylosing Spondylitis Disease Activity Score (BASDAI), the serum C-reactive protein (CRP) and IgA were measured by nephelometry, and erythrocyte sedimentation rate (ESR) was measured by Westergren's method. The median titers of anti-Gal(0) IgG were significantly elevated in patients with RA (167.85, 15.73 approximately 797.58 AU/mL) and AS/PsA (186.15, 34.71 approximately 651.19 AU/mL), compared to those of the normal controls (13.04, 12.00 approximately 202.43 AU/mL). The titers of the anti-Gal(0) IgG in patients with AS/PsA were correlated to the BASDAI scores (r (2) = 0.422, SEE = 1.443, p < 0.001) and serum CRP (r (2) = 0.345, SEE = 2.434, p < 0.001) but not to IgA (r (2) = 0.0259, SEE = 126.30, p < 0.001) or ESR (r (2) = 0.171, SEE = 31.053, p = 0.0059). Collectively, the anti-Gal(0) IgG is elevated and vaguely correlated with the disease activity of AS/PsA although its titers in these patients were erratic. The result of the present investigation has suggested that anti-Gal(0) IgG may be more ubiquitously present in inflammatory arthritides including RA or SpA.

Serum BLC/CXCL13 concentrations and renal expression of CXCL13/CXCR5 in patients with systemic lupus erythematosus and lupus nephritis.

OBJECTIVE: Systemic lupus erythematosus (SLE) is a prototype of systemic autoimmune disease in which cytokines such as B lymphocyte chemoattractant (BLC, or CXC motif ligand 13, CXCL13) may play important roles in pathogenesis. We investigated the implications of CXCL13 in SLE and lupus nephritis. METHODS: Serum samples from 425 patients with SLE and 106 healthy control individuals were analyzed for the concentration of CXCL13 by ELISA. Tissue expression of CXCL13 and its corresponding receptor CXCR5 were observed in lupus kidney. The CXCR5-bearing B cells in SLE patients were analyzed by flow cytometry. RESULTS: Serum levels of CXCL13 were higher in SLE patients compared to controls. SLE patients with lupus nephritis or positive anti-dsDNA antibodies had significantly higher serum CXCL13 levels. The peripheral venous blood B cells that bear CXCR5 were more abundant in SLE patients as detected by flow cytometry. CXCR5 and CXCL13 were highly expressed in the renal cortex from patients with lupus nephritis. CONCLUSIONS: Our results suggest that BLC/CXCL13 as well as its corresponding receptor, CXCR5, may play important roles in the pathogenesis of SLE and in lupus nephritis.

Altered glycosylation of Tamm-Horsfall glycoprotein derived from renal allograft recipients leads to changes in its biological function.

BACKGROUND: Human urinary Tamm-Horsfall glycoprotein (THP) is a pleotropic protein that binds different cytokines and stimulates various immunocompetent cells. It is unclear whether these important functions of THP are altered in renal transplant patients. METHODS: We purified THPs from normal individuals (N-THP) and renal transplant patients receiving potent immunosuppressants (R-THP). The carbohydrate (CHO) compositions of THPs were probed by lectin-blotting and lectin-binding ELISA. The functions of THP were assessed by immune cell-stimulation as well as C1q, IL-1beta, IL-8 and TNF-alpha-binding assays. The roles of CHO moieties in THPs were analyzed using CHO-degrading enzyme digestion. RESULTS: Compared to that of N-THP, the binding capacity of R-THP to Maackia amurensis, Galanthus nivalis and Datura stamonium decreased, indicating that R-THP contained lesser amount of Siaalpha(2,3)Gal/GalNAc, mannose residues, and beta(1,4)GlcNAc, but not GlcNAc/branched mannose. The binding capacity of R-THP to complement C1q and tumor necrosis factor (TNF)-alpha was also decreased. The stimulating effect of R-THP on mononuclear cell (MNC) proliferation and polymorphonuclear neutrophil (PMN) phagocytosis was less potent than that of N-THP. We found that the defective MNC-stimulation by R-THP was due to impaired NF-kappaB p52 nuclear translocation. The cell-stimulating effects of N- and R-THP could be abolished by digesting them with CHO-degrading enzymes, beta-galactosidase and neuraminidase. Interestingly, a potent apoptosis-inducing effect of R-THP on MNC and PMN was noted. CONCLUSIONS: R-THP is not only modified in glycosylation but bears an apoptosis-inducing capacity on MNC and PMN, leading to an impaired immune function in renal transplant patients.

Proinflammatory cytokines enhance COX-1 gene expression in cultured rat glomerular mesangial cells.

Glomerular mesangial cells (GMC) exert an essential maintaining effect on hemodynamic integrity and immune competence of the kidney through arachidonate metabolism. To clarify this, cultured rat GMC were measured for the expression and production of cyclooxygenase (COX) and excretion of prostaglandin (PG). The rat GMC spontaneously expressed type 1 cyclooxygenase (COX-1), but not COX-2. The PGE2 and thromboxane B2 (TXB2) were spontaneously produced by the cells. Interleukin (IL)-1beta (25 ng/ml), IL-8 (25 ng/ml), growth-related oncogene-alpha (GRO, 50 ng/ml) and tumor necrosis factor-alpha (TNF-alpha, 25 ng/ml) stimulated the COX-1 protein production as demonstrated by Western blot and enhanced PGE2 synthesis in GMC, beginning on 2 h of incubation, and steadily enhanced TXB2 synthesis over a 24-h period. Lipopolysaccharide (LPS, 100 ng/ml) enhanced both PGE2 and TXB2 syntheses from 2 h to at least 24 h of incubation. Collectively, the proinflammatory cytokines could enhance COX-1 but not COX-2 expression in GMC leading to increased PGE2 and TXB2 production. These biochemical events may be implicated in normal renal physiology as well as in pathogenesis of glomerular diseases.

Hypercalcemia in a renal transplant recipient suffering with Pneumocystis carinii pneumonia.

Hypercalcemia occurs frequently after renal transplantation. Preexisting hyperparathyroidism is the most common cause of post-transplantation hypercalcemia. We describe a renal transplant recipient infected with Pneumocystis carinii pneumonia (PCP) who developed hypercalcemia, elevated 1,25-dihydroxyvitamin D, and suppressed parathyroid hormone levels. This phenomenon mimics the extrarenal production of 1,25-dihydroxyvitamin D by activated alveolar macrophages in granulomatous diseases with hypercalcemia. To the best of our knowledge, this is the first report of 1,25-dihydroxyvitamin D-mediated hypercalcemia caused by PCP in a renal transplant recipient. This entity should be included in the differential diagnosis for renal transplant recipients with hypercalcemia, especially in patients who develop lung infections.

An open-label, crossover study of a new phosphate-binding agent in haemodialysis patients: ferric citrate.

BACKGROUND: Hyperphosphataemia contributes to secondary hyperparathyroidism and renal osteodystrophy in patients with end-stage renal disease (ESRD). Calcium salts are widely employed to bind dietary phosphate (P) but they may promote positive net calcium balance and metastatic calcification. We recently reported that ferric compounds bind intestinal phosphate in studies of normal and azotemic rats. METHODS: To extend this observation, we performed an open-label, random order, crossover comparison study of ferric citrate and calcium carbonate in haemodialysis patients from two teaching hospitals. The study sample consisted of 23 women and 22 men with an average age of 52.5 +/- 11.8 (SD) years and an average weight of 54.5 +/- 10.7 kg. All forms of iron therapy were discontinued. Two weeks before the study, patients were instructed to discontinue all P-binding agents. The patients were randomly assigned to receive either calcium carbonate (3 g/day) or ferric citrate (3 g/day) for 4 weeks followed by a 2 week washout period, and then crossed over to the other P-binding agent for 4 weeks. RESULTS: From a baseline concentration of 5.6 +/- 1.5 mg/dl, the serum P increased during the washout period to 7.2 +/- 1.9 mg/dl prior to calcium carbonate treatment, and to 6.7 +/- 1.9 mg/dl prior to ferric citrate treatment. The serum P concentration fell significantly during treatment with both calcium carbonate (7.2 +/- 1.9 to 5.2 +/- 1.5 mg/dl, P<0.0001) and ferric citrate (6.7 +/- 1.9 to 5.7 +/- 1.6 mg/dl, P<0.0001). The results were not influenced by order of treatment. Under the conditions of the study protocol, ferric citrate was less effective than calcium carbonate at lowering the serum phosphate concentration. The serum Ca concentration increased during treatment with calcium carbonate but not ferric citrate. Ferric citrate treatment did not affect the serum concentration of aluminium. Ferric citrate treatment was associated with mild and generally tolerable gastrointestinal symptoms. CONCLUSION: Ferric citrate shows promise as a means of lowering the serum phosphate concentration in haemodialysis patients. Further studies are needed to find the optimal dose.