Immune characteristics of renal allograft donors with mesangial IgA deposition.

BACKGROUND: There are few studies describing the prevalence and immune features of people with subclinical mesangial immunoglobulin A (IgA) deposition in the Chinese population. We sought to investigate the prevalence of mesangial IgA deposition among kidney donors and the immune characteristics of donors with mesangial IgA deposition. METHODS: Fifty blood-related living donors with zero-hour allograft biopsies obtained at Peking University First Hospital were enrolled. Galactose-deficient IgA1 (Gd-IgA1) in glomerular deposits was examined by double immunofluorescent staining using the specific monoclonal antibody KM55. Plasma IgA, IgA1, Gd-IgA1 and antibodies directed against Gd-IgA1 were measured using enzyme-linked immunosorbent assay. RESULTS: Thirteen of 50 (26%) donors had mesangial IgA deposition, which was confirmed by both immunofluorescence and electron microscopy. The levels of plasma IgA, IgA1 and Gd-IgA1 were all increased in donors with IgA deposition compared with those without IgA deposition (mean ± SD, 3.54 ± 0.505 versus 2.356 ± 0.265 mg/ml, p = 0.049; 3.003 ± 0.4048 versus 2.356 ± 0.265 mg/ml, p = 0.057; and 4.719 ± 0.4357 versus 3.356 ± 0.4707 ug/ml, p = 0.0440, respectively). Colocalized IgA1 and Gd-IgA1 indicated that there were galactose-deficient IgA1 deposits in the glomerular mesangium. While donors with IgA deposition showed lower levels of IgG anti-glycan antibodies than patients with IgA nephropathy (37.71 ± 8.886 versus 78.86 ± 5.155 units/ml, p = 0.001). CONCLUSIONS: The immune features of donors with IgA deposition, including IgA1 and Gd-IgA1 deposition, were similar to those of patients with IgA nephropathy, but donors with IgA deposition had lower levels of antiglycan antibodies, which may explain the subclinical status of IgA deposition in donors. Mesangial IgA deposition was common in the Chinese blood related donors cohort, further large study with both living and cadaveric donor kidneys was still needed to confirm these findings.

Glomerular C4 deposition and glomerulosclerosis predict worse renal outcomes in Chinese patients with IgA nephropathy.

BACKGROUND: Immunoglobulin A nephropathy (IgAN) is a clinical and pathological syndrome with heterogenous manifestation and progression. Complement activation is involved in the disease. However, the clinical significance of C4 deposition in IgAN is obscure. METHODS: A multicenter retrospective study was conducted in biopsy-proven IgAN patients. Based on mesangial C4 deposition, patients were divided into two groups. The baseline clinical data and immunopathological phenotypes were compared. The composite endpoint was defined as eGFR decline greater than 50%, doubling of baseline serum creatinine, the occurrence of end-stage renal disease (ESRD). RESULTS: A total of 642 IgAN patients were recruited, with 41 patients showing mesangial C4 deposition. The mesangial C4 positive group showed lower serum albumin, higher proteinuria, and a higher rate of IgG, IgM, and C1q mesangial deposition. After a median follow-up of 43.18 months, 81 (12.62%) patients achieved the composite endpoint. The multivariate Cox regression models identified glomerular C4 deposition (hazard ratios [HR] = 3.22, 95% confidence intervals [CI] = 1.51-6.87, p < 0.01), global sclerosis (G1 vs. G0, HR = 1.90, 95%CI = 1.02-3.52, p = 0.04; G2 vs. G0, HR = 3.72, 95%CI = 1.98-7.00, p < 0.01), male (HR = 1.80, 95%CI = 1.10-2.97, p = 0.02), serum creatinine (HR = 1.01, 95%CI = 1.00-1.01, p < 0.01), triglyceride (HR = 1.17, 95%CI = 1.01-1.35, p = 0.04), proteinuria (HR = 1.07, 95%CI = 1.01-1.13, p = 0.02), serum C3 level (HR = 0.05, 95%CI = 0.01-0.25, p < 0.01), and serum C4 level (HR = 99.59, 95%CI = 8.69-1140.89, p < 0.01) as independent risk factors for poor renal outcomes. CONCLUSIONS: Glomerular mesangial C4 deposition and global sclerosis are independent predictors for poor prognosis in IgAN patients.

Clinical relevance of membrane attack complex deposition in children with IgA nephropathy and Henoch-Schönlein purpura.

BACKGROUND: IgA nephropathy (IgAN) and Henoch-Schönlein purpura are common glomerular disorders in children sharing the same histopathologic pattern of IgA deposits within the mesangium, even if their physiopathology may be different. Repeated exposure to pathogens induces the production of abnormal IgA1. The immune complex deposition in the renal mesangium in IgAN or potentially in small vessels in Henoch-Schönlein purpura induces complement activation via the alternative and lectin pathways. Recent studies suggest that levels of membrane attack complex (MAC) in the urine might be a useful indicator of renal injury. Because of the emerging availability of therapies that selectively block complement activation, the aim of the present study is to investigate whether MAC immunostaining might be a useful marker of IgA-mediated renal injury. METHODS: We conducted immunohistochemistry analysis of the MAC on renal biopsies from 67 pediatric patients with IgAN and Henoch-Schönlein purpura. We classified their renal biopsies according to the Oxford classification, retrieved symptoms, biological parameters, treatment, and follow-up. RESULTS: We found MAC expression was significantly related to impaired renal function and patients whose clinical course required therapy. MAC deposits tend to be more abundant in patients with decreased glomerular filtration rate (p = 0.02), patients with proteinuria > 0.750 g/day/1.73 m2, and with nephrotic syndrome. No correlation with histological alterations was observed. CONCLUSIONS: We conclude that MAC deposition could be a useful additional indicator of renal injury in patients with IgAN and Henoch-Schönlein purpura, independent of other indicators.

Phosphatidylethanolamine binding protein-4 (PEBP4) is increased in IgA nephropathy and is associated with IgA-positive B-cells in affected kidneys.

IgA nephropathy (IgAN) is the most common glomerulonephritis worldwide and a major cause of chronic kidney disease and failure. IgAN is driven by an autoimmune reaction against galactose-deficient IgA1 that results in the generation of autoantibodies and large IgG-IgA immune complexes. Immune complexes accumulate in the glomerular mesangium causing chronic inflammation and renal scarring. A significant proportion of IgAN patients develop end-stage kidney disease and require dialysis or transplantation. Currently, there are no approved specific therapies that can ameliorate the systemic autoimmune reaction in IgAN and no biomarkers that can predict renal inflammation and scarring. In this study, we used shotgun LC-MS/MS proteomics to compare small volumes of urine from healthy subjects and IgAN patients. We identified multiple urine proteins with unknown renal or IgAN function. Our attention was captured by the increase of phosphatidylethanolamine binding protein-4 (PEBP4) in IgAN urine. The function of PEBP4 in IgAN or renal disease is unknown. Increased levels of urine and serum PEBP4 were subsequently validated in different cohorts of IgAN patients and PEBP4 was linked to declining kidney function in IgAN. Strong PEBP4 staining was sporadically seen in IgAN kidney biopsies, colocalising with IgA in glomeruli and in the lumen of kidney tubules. In a small number of IgAN biopsies, PEBP4 colocalised with IgA and CD19 while the increased excretion of PEBP4 in IgAN urine was accompanied by increased excretion of classic B-cell factors BAFF, BCMA and TACI as well as IgA and IgG. PEBP4 is a new IgAN-related protein with unknown function and a likely renal disease marker in urine and serum.

Development of anti-glomerular basement membrane glomerulonephritis during the course of IgA nephropathy: a case report.

BACKGROUND: Anti-glomerular basement membrane (GBM) glomerulonephritis does not usually coexist with another glomerulonephritis such as IgA nephropathy. We present a rare case having a combination of these two diseases, and furthermore, histological evaluation could be performed before and after the development of anti-GBM glomerulonephritis over a period of only10 months. CASE PRESENTATION: A 66-year-old woman was admitted with complaints of microscopic hematuria and mild proteinuria for the past 3 years. Serum creatinine level was normal at that time. The first renal biopsy was performed. Light microscopy revealed mesangial proliferative glomerulonephritis with fibro-cellular crescents in one out of 18 glomeruli, excluding one global sclerotic glomerulus. Immunofluorescence (IF) showed IgA and C3 deposition in the mesangium. Therefore, the diagnosis was IgA nephropathy. Eight months later, the patient's serum creatinine suddenly rose to 4.53 mg/dL and urinalysis showed 100 red blood cells per high power field with nephrotic range proteinuria (12.3 g/gCr). The serological tests revealed the presence of anti-GBM antibody at the titer of 116 IU/mL. Treatments were begun after admission, consisting of hemodialysis, plasma exchange, and intravenous methylprednisolone pulse therapy. At 4 weeks after admission, the second renal biopsy was performed. Light microscopy revealed crescents in 18 of 25 glomeruli, excluding six global sclerotic glomeruli. IF showed linear IgG deposition along the GBM in addition to granular IgA and C3 deposition. Based on these findings, the diagnosis of anti-GBM glomerulonephritis and IgA nephropathy was confirmed. Renal function was not restored despite treatment, but alveolar hemorrhage was prevented. CONCLUSIONS: We report a patient with a diagnosis of anti-GBM disease during the course of IgA nephropathy. This case strongly suggests that the presence of autoantibodies should be checked to rule out overlapping autoimmune conditions even in patient who have previously been diagnosed with chronic glomerulonephritis, such as IgA nephropathy, who present an unusually rapid clinical course.

The role of transcriptional factor D-site-binding protein in circadian CCL2 gene expression in anti-Thy1 nephritis.

Mesangial proliferative glomerulonephritis (MsPGN) is an inflammatory disease, but both the nature of disease progression and its regulation remain unclear. In the present study, we monitored the course of anti-Thy1 nephritis from days 1 to 5 and established gene expression profiles at each time point using microarrays to explore the development of inflammation. According to the gene expression profiles, macrophage infiltration (triggered by CCL2 activation) was evident on day 1 and enhanced inflammation over the next few days. We screened for genes with expression levels similar to CCL2 and found that the upregulation of the circadian gene albumin D-site-binding protein (DBP) was involved in CCL2 activation in mesangial cells. More importantly, CCL2 expression showed oscillatory changes similar to DBP, and DBP induced peak CCL2 expression at 16:00 a clock on day 1 in the anti-Thy1 nephritis model. We knocked down DBP through transfection with a small interfering RNA (siRNA) and used RNA sequencing to identify the DBP-regulated TNF-α-CCL2 pathway. We performed chromatin immunoprecipitation sequencing (ChIP-Seq) and the dual luciferase assay to show that DBP bound to the TRIM55 promoter, regulating gene expression and in turn controlling the TNF-α-CCL2 pathway. In conclusion, DBP-regulated circadian CCL2 expression by the TRIM55-TNF pathway in injured mesangial cells at an early stage, which promoted macrophage recruitment and in turn triggered infiltration and inflammation in a model of anti-Thy1 nephritis.

Acute renal failure in a patient with PR3-ANCA and monoclonal immunoglobulin deposition disease: Case report.

RATIONALE: Acute renal failure developing over a short period of time with evidence of glomerular disease by urine sediment microscopy characterizes the clinical syndrome of rapidly progressive glomerulonephritis (RPGN), of which the most common causes are ANCA-associated glomerulonephritis (GN), immune-complex mediated GN and anti-GBM disease. PATIENT CONCERNS: This was a middle-aged gentleman who presented with acute renal failure and a positive PR3-ANCA. DIAGNOSIS: Renal biopsy showed an unusual combination of PR3-ANCA GN with focal crescents, monoclonal immunoglobulin deposition disease (MIDD) and mesangial IgA deposition on renal biopsy. INTERVENTIONS: Serum and urine protein electrophoresis (UPEP) and immunofixation showed no detectable monoclonal paraprotein; bone marrow biopsy was negative for plasma cell neoplasia. He received high dose steroids and rituximab. OUTCOMES: The patient did not respond to treatment and progressed to end-stage renal failure within 2 months after presentation. LESSONS: To our knowledge, the simultaneous occurrence of MIDD, PR3-ANCA and mesangial IgA has not been reported. This case highlights not only the diagnostic but also the therapeutic challenges that such a complex case presentation poses to clinicians, where the culprit may not always be what would seem most obvious (such as ANCA in a patient with RPGN) but may, in fact, be an underlying and unsuspected disease, or possibly a combination of both.

Post-transplant immunoglobulin A deposition and nephropathy in allografts.

Post-transplant immunoglobulin A (IgA) nephropathy (IgAN) in the allograft is the major cause of allograft loss. Using a protocol biopsy, latent mesangial IgA deposition (IgAD) can be detected in the allograft. Latent IgAD is distinguished from IgAN by the absence of urinary abnormalities, although IgA is observed in the mesangium. However, the pathophysiology and most appropriate treatment strategy for latent mesangial IgAD in the allograft remain to be fully determined. Importantly, it is unknown whether all cases of post-transplant asymptomatic IgAD progress to symptomatic IgAN; indeed, IgA deposits disappear in some cases. The differences in allograft prognosis between asymptomatic IgAD and IgAN have also not been determined. Non-invasive methods of diagnosis of IgAD in the allograft using serological and pathological biomarkers are being developed. Possible serum biomarkers include serum galactose-deficient IgA1 (Gd-IgA1), Gd-IgA1-specific IgG and Gd-IgA1-specific IgA, and its immune complexes. Immunofluorescence analysis using Gd-IgA1 monoclonal antibody may provide a pathological biomarker. These serological and pathological biomarkers may be suitable for the characterization of the stage of IgAD. However, there is insufficient information regarding whether serological and pathological biomarkers can predict the progression of asymptomatic IgAD to symptomatic IgAN. We propose that the pathogenesis of IgAN can be defined through the clinical study of IgAD in the allograft using protocol biopsies conducted by nephrologists involved in clinical kidney transplantation.

Case report on pathogenetic link between gluten and IgA nephropathy.

BACKGROUND: A relationship between IgA nephropathy (IgAN) and celiac disease (CD) has been reported. We show the pathogenetic link for the first time. CASE PRESENTATION: A 39-year-old man with cystic fibrosis (CF) and CF-related diabetes started to present gross hematuria, back pain and headache. At admission, laboratory analysis showed increase in serum creatinine of 1.5 mg/dl, together with hematuria and mild proteinuria (1 g/24 h). He underwent a renal biopsy to investigate the cause of hematuria and renal failure. Biopsy was consistent with IgAN. In view of patient reported dyspepsia, an upper gastrointestinal endoscopy with duodenal biopsies was undertaken and was normal. We looked for mucosal deposits of tTG-2 in the duodenum and the renal mesangium. tTG-2 deposits were found both in the duodenum and in renal biopsies, where they topographically replicated mesangial IgA deposits. After one year on a continued gluten containing diet, the patient developed a Marsh 2 type duodenal pathology. CONCLUSIONS: Our findings suggest a connection between CD and IgAN in terms of an immune-mediated gluten-induced pathogenesis even in the absence of villous atrophy and serum celiac autoantibodies.

Predominant but silent C1q deposits in mesangium on transplanted kidneys - long-term observational study.

BACKGROUND: C1q nephropathy (C1qN) was first described as glomerular disease characterized by predominant meangial C1q deposits in patients with proteinuria and no evidence of systemic lupus erythematosus. Several studies, however, revealed the clinical heterogeneity of C1qN, showing some cases with normal urinalysis. To confirm the existence of cases with predominant mesangial C1q deposits and negative or mild proteinuria and/or hematuria, we investigated renal graft biopsy specimens showing negative to mild proteinuria (less than or equal to 1+ by dip stick test) and/or hematuria. METHODS: Eligible participants were kidney transplant cases who corresponded to the criteria for C1qN and were followed more than 10 years. Their medical records were reviewed to determine the age at detection of predominant mesangial C1q deposits, gender, original renal disease and reason for renal graft biopsy, blood pressure, degree of proteinuria and hematuria, and serum creatinine levels. RESULTS: From 414 cases in adults and children, five pediatric patients (the male to female ratio, 1:1.5) were eligible. At the time when predominant mesangial C1q deposits were detected, 2 cases presented with mild proteinuria without hematuria, but the other 3 cases showed normal urinalysis. Light microscopy revealed minor glomerular abnormality in all the cases. Immunofluorescent study showed predominant mesangial C1q deposits with IgG, IgM and C3 in all cases. All selected specimens presented electron dense-depos in the mesangium. Ten years later from the detection, 2 cases continued to be normal urinalysis and 3 cases had mild proteinuria without hematuria. During this follow-up period, no cases presented with persistent proteinuria and/or hematuria greater than or equal to 2+ by dip stick test. And no cases developed systemic lupus erythematosus. Follow-up renal graft biopsies were performed once in 2 cases 8 years later from the detection. They showed minor glomerular abnormalities. C1q deposit disappeared in one case. In another case, immunofluorescent study was not examined. CONCLUSIONS: This long-term observational study on transplanted kidneys confirms the existence of cases with predominant but silent C1q deposits in the mesangium who have negative or mild proteinuria.

Mesangial C4d Deposits in Early IgA Nephropathy.

BACKGROUND AND OBJECTIVES: The prognostic value of mesangial C4d deposits in IgA nephropathy has been analyzed in patients with reduced GFR but has not been analyzed in those with normal kidney function. The main objective of the study was to analyze the prognostic value of C4d deposits and association with response to treatment in patients with IgA nephropathy and normal GFR. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This retrospective cohort study included 190 patients with idiopathic IgA nephropathy diagnosed by kidney biopsy between 1988 and 2005. The patients had GFR≥80 ml/min per 1.73 m2 at the time of diagnosis, and they had a paraffin-embedded kidney biopsy with eight glomeruli available. RESULTS: In total, 170 (89%) and 20 (11%) patients were >18 and <18 years old, respectively; median (interquartile range) follow-up was 15 (12-22) years. Mesangial C4d deposit prevalence was 20% (38 of 190). At diagnosis, C4d-positive versus -negative patients had higher protein-to-creatinine ratio (median [interquartile range]: 1.94 g/g [0.9-3.1] versus 1.45 g/g [0.9-2.2]; P=0.04). During follow-up, C4d-positive patients showed a higher number of nephritic flares (median [range]: 1.4 [0-5] versus 0.9 [0-2]; P=0.04), had a higher protein-to-creatinine ratio (median [interquartile range]: 1.32 g/g [0.7-1.7] versus 0.89 g/g [0.1-1.3]; P<0.01), were more prone to receive repeated treatment with corticosteroids (45% versus 24%; P<0.01), and showed a larger reduction in eGFR (-1.6 versus -0.8 ml/min per 1.73 m2 per year; P=0.04). Furthermore, the presence of mesangial C4d deposits was an independent predictor of long-term kidney survival. CONCLUSIONS: C4d deposits may be one of the earliest poor prognostic variables available for patients with idiopathic IgA nephropathy and normal kidney function at the time of diagnosis. However, Cd4 deposits alone are not associated with the response to angiotensin blockers or corticosteroid treatment.

Validation study of Oxford Classification of IgA Nephropathy: the significance of extracapillary hypercellularity and mesangial IgG immunostaining.

The Oxford classification (OC) of IgA Nephropathy (IgAN) identified mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), and tubular atrophy/interstitial fibrosis (T) as predictors of outcome. We aimed to validate the OC and to investigate the clinical significance of extracapillary hypercellularity and IgG immunostaining. We examined the renal outcome at December 31, 2014, of 121 adult patients with biopsy proven primary IgAN between 2003 and 2013. The primary endpoint was doubling of serum creatinine or renal replacement therapy initiation. The mean observation period was 59.7 months. Thirty-one percent of the patients presented with a grade of extracapillary hypercellularity. In comparison with the group with no crescents, they had higher grade of inflammation, lower eGFR and increased proteinuria. There were no differences between the IgA and IgA&IgG immunostaining groups regarding the disease progression risk factors. Mean kidney survival time for the entire cohort was 10.6 (9.1, 12.0) years. In the Cox regression model, the independent predictors of decreased renal survival were eGFR at time of biopsy, S1 and the presence of crescents. Our study showed that extracapillary proliferation and S1 had the greatest importance in establishing the renal prognosis of patients with IgAN.

[Development of mesangial immunoglobulin IgA glomerulonephritis and p-ANCA positivity in a patient with psoriatic arthritis]. / Insorgenza di glomerulonefrite a depositi mesangiali di IgA e positività di p-ANCA in un paziente affetto da artrite psoriasica in trattamento con etanercept.

Tumor necrosis factor (TNF) inhibitors are widely used for the treatment of various rheumatic diseases. These agents may lead to development of systemic autoimmune diseases and renal complications. We report a patient with psoriatic arthritis and renal failure treated with two TNF inhibitors (Etanercept and then Adalimumab). After this treatment he developed proteinuria with nephrotic syndrome. A renal biopsy was performed highlighting GN with mesangial IgA deposits. Then he developed p-ANCA positivity. Following that, etanercept and adalimumab were stopped and a treatment by corticosteroids was initiated, but renal function decreased. Currently the patient is treated by haemodialysis. In our patient, the pathogenic role for anti-TNF therapy is suggested by the close temporal relationship with development of glomerular disease and by the improvement in proteinuria after drug withdrawal. However, the patient was treated once more with TNF agents, so he developed end stage renal disease.

Immune Complex-Type Deposits in the Fischer-344 to Lewis Rat Model of Renal Transplantation and a Subset of Human Transplant Glomerulopathy.

BACKGROUND: Antibody-mediated rejection is a leading cause for renal transplant loss. Rodent models are useful to dissect pathomechanisms and to develop treatment strategies. Although used for decades as a model, glomerular histopathological findings of Fischer-344 kidneys transplanted into Lewis rats have never been comprehensively described. METHODS: Kidneys from Fischer-344 rats were transplanted into Lewis rats as life-sustaining allografts without immunosuppression. Lewis isografts and normal Fischer-344 kidneys served as controls. Grafts were harvested at 9 days, 6 and 26 weeks. Histopathological examination included light microscopy, immunohistochemistry, and morphometry. Findings were compared with 51 human biopsies with transplant glomerulopathy. RESULTS: Most glomerular findings in rat allografts resembled human acute and chronic antibody-mediated rejection with glomerulitis, microthrombosis, microaneurysms, glomerular hypertrophy, podocyte loss, glomerular basement membrane splitting, and secondary focal and segmental glomerulosclerosis. In line with previous reports on nonendothelial antigens, glomerular immunoglobulin and C4d deposition was mostly nonendothelial. Only in 26-week allografts, we found mesangial and subendothelial immune complex-type electron-dense deposits. Similar deposits were found in 8 of 51 human biopsies with transplant glomerulopathy after rigorous exclusion of immune complexes of other cause, particularly recurrent glomerulonephritis and hepatitis C. CONCLUSIONS: Thus, our model closely reflects the glomerular changes of acute antibody-mediated rejection in humans and of a special subset of human transplant glomerulopathy. The significance of alloimmune immune complex-type deposits in human transplants deserves further investigation.

Evolution of IgA nephropathy into anaphylactoid purpura in six cases--further evidence that IgA nephropathy and Henoch-Schonlein purpura nephritis share common pathogenesis.

BACKGROUND: As the morphological and immunohistochemical manifestations of immunoglobulin A (IgA) nephropathy and Henoch-Schonlein purpura nephritis (HSPN) are very similar, they are considered to share a common pathogenesis. Although HSPN usually develops after the appearance of anaphylactoid purpura, we have encountered patients whose renal symptoms preceded purpura. METHODS: We reviewed the clinical courses of patients who were first diagnosed with IgA nephropathy, but developed purpura later, at the National Center for Child Health and Development in Tokyo, Japan. RESULTS: Of the 53 patients who were diagnosed with primary IgA nephropathy at our institute during the study period (March 2002 to July 2015), six (11 %) developed anaphylactoid purpura after the diagnosis of primary IgA nephropathy and therefore met the inclusion criteria. Duration between the onset of nephritis and subsequent appearance of purpura ranged from 5 months to 14 years. One patient reached end-stage renal failure due to IgA nephropathy and developed purpura after renal transplantation. All renal biopsies performed before the appearance of purpura showed mesangial proliferation with predominant IgA deposits. Urinary findings deteriorated in three patients after the appearance of purpura, including one patient who developed rapidly progressive glomerulonephritis. Renal biopsy findings worsened in two patients. At the last observation, two patients showed mild renal insufficiency. CONCLUSIONS: Our clinical experience and previous reports support the argument that IgA nephropathy and HSPN are different manifestations of a single disease. Hence, it is acceptable to consider that they are variants of a single disease.

Successful modulation of murine lupus nephritis with tuftsin-phosphorylcholine.

In areas where helminths infections are common, autoimmune diseases are rare. Treatment with helminths and ova from helminths, improved clinical findings of inflammatory bowel disease, multiple-sclerosis and rheumatoid-arthritis. The immunomodulatory functions of some helminths were attributed to the phosphorylcholine (PC) moiety. We aimed to decipher the tolerogenic potential of Tuftsin-PC (TPC) compound in mice genetically prone to develop lupus. Lupus prone NZBXW/F1 mice received subcutaneously TPC (5 µg/1 ml), 3 times a week starting at 14 weeks age. Autoantibodies were tested by ELISA, T-regulatory-cells by FACS, cytokines profile by RT-PCR and cytokines protein levels by DuoSet ELISA. Glomerulonephritis was addressed by detection of proteinuria, and immunoglobulin complex deposition in the mesangium of the kidneys of the mice by immunofluorescence. Our results show that TPC attenuated the development of glomerulonephritis in lupus prone mice, in particular, it ameliorated proteinuria (p < 0.02), and reduced immunoglobulin deposition in the kidney mesangium. TPC also enhanced the expression of TGFß and IL-10 (p < 0.001), and inhibited the production of IFNγ and IL-17 (p < 0.03). TPC Significantly enhanced the expansion of CD4+CD25+FOXP3+ T-regulatory cells (Tregs) phenotype in the treated mice. These data indicate that TPC hampered lupus development in genetically lupus prone mice which was exemplified by moderate glomerulonephritis, attenuation of pro-inflammatory cytokines and enhancement of anti-inflammatory cytokines expression, as well as Tregs expansion. Our results propose harnessing novel natural therapy for lupus patients.

The kinetics of glomerular deposition of nephritogenic IgA.

Whether IgA nephropathy is attributable to mesangial IgA is unclear as there is no correlation between intensity of deposits and extent of glomerular injury and no clear mechanism explaining how these mesangial deposits induce hematuria and subsequent proteinuria. This hinders the development of a specific therapy. Thus, precise events during deposition still remain clinical challenge to clarify. Since no study assessed induction of IgA nephropathy by nephritogenic IgA, we analyzed sequential events involving nephritogenic IgA from IgA nephropathy-prone mice by real-time imaging systems. Immunofluorescence and electron microscopy showed that serum IgA from susceptible mice had strong affinity to mesangial, subepithelial, and subendothelial lesions, with effacement/actin aggregation in podocytes and arcade formation in endothelial cells. The deposits disappeared 24-h after single IgA injection. The data were supported by a fluorescence molecular tomography system and real-time and 3D in vivo imaging. In vivo imaging showed that IgA from the susceptible mice began depositing along the glomerular capillary from 1 min and accumulated until 2-h on the first stick in a focal and segmental manner. The findings indicate that glomerular IgA depositions in IgAN may be expressed under the balance between deposition and clearance. Since nephritogenic IgA showed mesangial as well as focal and segmental deposition along the capillary with acute cellular activation, all glomerular cellular elements are a plausible target for injury such as hematuria.

Identification of distinct glycoforms of IgA1 in plasma from patients with immunoglobulin A (IgA) nephropathy and healthy individuals.

Immunoglobulin A nephropathy (IgAN) is the most common form of glomerulonephritis worldwide and is histologically characterized by the deposition of IgA1 and consequent inflammation in the glomerular mesangium. Prior studies suggested that serum IgA1 from IgAN patients contains aberrant, undergalactosylated O-glycans, for example, Tn antigen and its sialylated version, SialylTn (STn), but the mechanisms underlying aberrant O-glycosylation are not well understood. Here we have used serial lectin separation technologies, Western blot, enzymatic modifications, and mass spectrometry to explore whether there are different glycoforms of IgA1 in plasma from patients with IgAN and healthy individuals. Although total plasma IgA in IgAN patients was elevated ∼ 1.6-fold compared with that in healthy donors, IgA1 in all samples was unexpectedly separable into two distinct glycoforms: one with core 1 based O-glycans, and the other exclusively containing Tn/STn structures. Importantly, Tn antigen present on IgA1 from IgAN patients and controls was convertible into the core 1 structure in vitro by recombinant T-synthase. Our results demonstrate that undergalactosylation of O-glycans in IgA1 is not restricted to IgAN and suggest that in vivo inefficiency of T-synthase toward IgA1 in a subpopulation of B or plasma cells, as well as overall elevation of IgA, may contribute to IgAN pathogenesis.

Expression of macrophage markers in cryoglobulinemic glomerulonephritis - a possible role of CXCL9.

PURPOSE: Cryoglobulinemic glomerulonephritis (CGGN) is a type of membranoproliferative glomerulonephritis (MPGN) that develops in patients with systemic cryoglobulinemia. To date the exact pathogenesis of CGGN remains unclear. It has been suggested that macrophages may be significant contributors to the glomerular injury in this disease. In our study we attempt to characterize the macrophages in human CGGN using classical activation and regulatory macrophage markers. MATERIAL AND METHOD: We searched our database for renal biopsy cases of CGGN. Macrophages were detected using a monoclonal anti-CD68 antibody. Two groups of macrophage markers were used: classical activation markers, including iNOS, CXCL9 and CCL20, and regulatory markers: SPHK1 and LIGHT. The stains were performed using immunohistochemical method. RESULTS: Five patients with CGGN were identified. Four patients had systemic cryoglobulinemia and two had a serological evidence of hepatitis C virus infection. In all cases the glomeruli contained numerous macrophages. Staining for activatory macrophage markers revealed a strong nuclear staining for CXCL9 in numerous cells, including those corresponding to the macrophage location. Staining for the other activatory markers, as well as staining for regulatory markers, was not significant. CONCLUSION: In this study of human CGGN we showed a striking expression of cytokine CXCL9, a classical macrophage activation marker, by the macrophages and possibly other cell types within the glomeruli. This observation points to the possible role of classically activated macrophages in the pathogenesis of MPGN. If this observation is confirmed on a larger group of patients, the cytokine CXCL9 could become a potential therapeutic target for human CGGN.