Variation in complement factor H affects complement activation in immunoglobulin A vasculitis with nephritis.

BACKGROUND: Immunoglobulin A (IgA) vasculitis with nephritis (IgAVN) and IgA nephropathy (IgAN) are widely considered as related diseases. Considerable evidences support the notion of involvement of complement activation in both IgAVN and IgAN. Our previous studies identified a genetic variant in complement factor H (CFH), rs6677604, as an IgAN-susceptible variant by genome-wide association study, and further confirmed its linkage to CFHR3-1Δ and proved its influence on complement activation and thereby on IgAN susceptibility. AIM: To explore the role of rs6677604 in complement activation of IgAVN. METHODS: In this study, we enrolled 632 patients with IgAVN, 1178 patients with IgAN and 902 healthy controls. The genotype of rs6677604 was measured by TaqMan allele discrimination assays or was extracted from genome-wide association study data. RESULTS: The frequency of the rs6677604-A allele was significantly higher in IgAVN than in IgAN. However, no significant differences were observed between IgAVN and the controls. Higher complement factor H (FH) levels were observed in IgAVN than IgAN, and positive correlation between circulating FH and C3 levels was present in IgAVN. In both IgAVN and IgAN, rs6677604-A was associated with less intensity of glomerular C3 deposits. In agreement with the higher frequency of rs6677604-A in IgAVN, the glomerular C3 deposits of patients with IgAVN were less intense than those in IgAN. CONCLUSION: Our findings suggest that genetic variation in CFH (rs6677604) is involved in the phenotype of complement activation in both IgAVN and IgAN. Moreover, rs6677604 might contribute to the difference of complement activation intensity between IgAVN and IgAN.

Mechanism of ELL-associated factor 2 and vasohibin 1 regulating invasion, migration, and angiogenesis in colorectal cancer.

BACKGROUND: As a novel endogenous anti-angiogenic molecule, vasohibin 1 (VASH1) is not only expressed in tumor stroma, but also in tumor tissue. Moreover, studies have shown that VASH1 may be a prognostic marker in colorectal cancer (CRC). Knockdown of VASH1 enhanced transforming growth factor-ß1 (TGF-ß1)/Smad3 pathway activity and type I/III collagen production. Our previous findings suggest that ELL-associated factor 2 (EAF2) may play a tumor suppressor and protective role in the development and progression of CRC by regulating signal transducer and activator of transcription 3 (STAT3)/TGF-ß1 signaling pathway. However, the functional role and mechanism of VASH1-mediated TGF-ß1 related pathway in CRC has not been elucidated. AIM: To investigate the expression of VASH1 in CRC and its correlation with the expression of EAF2. Furthermore, we studied the functional role and mechanism of VASH1 involved in the regulation and protection of EAF2 in CRC cells in vitro. METHODS: We collected colorectal adenocarcinoma and corresponding adjacent tissues to investigate the clinical expression of EAF2 protein and VASH1 protein in patients with advanced CRC. Following, we investigated the effect and mechanism of EAF2 and VASH1 on the invasion, migration and angiogenesis of CRC cells in vitro using plasmid transfection. RESULTS: Our findings indicated that EAF2 was down-regulated and VASH1 was up-regulated in advanced CRC tissue compared to normal colorectal tissue. Kaplan-Meier survival analysis showed that the higher EAF2 Level group and the lower VASH1 Level group had a higher survival rate. Overexpression of EAF2 might inhibit the activity of STAT3/TGF-ß1 pathway by up-regulating the expression of VASH1, and then weaken the invasion, migration and angiogenesis of CRC cells. CONCLUSION: This study suggests that EAF2 and VASH1 may serve as new diagnostic and prognostic markers for CRC, and provide a clinical basis for exploring new biomarkers for CRC. This study complements the mechanism of EAF2 in CRC cells, enriches the role and mechanism of CRC cell-derived VASH1, and provides a new possible subtype of CRC as a therapeutic target of STAT3/TGF-ß1 pathway.

Collectin11 and Complement Activation in IgA Nephropathy.

BACKGROUND AND OBJECTIVES: IgA nephropathy is the most common primary GN worldwide. Previous research demonstrated that collectin11, an initiator of the complement lectin pathway, was involved in both AKI and chronic tubulointerstitial fibrosis. Here, we investigated the potential role of collectin11 in the pathogenesis of IgA nephropathy. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The deposition of collectin11 and other complement proteins was detected in glomeruli of 60 participants with IgA nephropathy by immunofluorescence. In vitro, human mesangial cells were treated with IgA1-containing immune complexes derived from participants with IgA nephropathy. Then, the expression of collectin11 in mesangial cells was examined by quantitative RT-PCR and immunofluorescence. The codeposition of collectin11 with IgA1 or C3 on mesangial cells was detected by immunofluorescence and proximity ligation assays. RESULTS: In total, 37% of participants with IgA nephropathy (22 of 60) showed codeposition of collectin11 with IgA in the glomerular mesangium. Using an injury model of mesangial cells, we demonstrated that IgA1-immune complexes derived from participants with IgA nephropathy increased the secretion of collectin11 in mesangial cells with the subsequent deposition of collectin11 on the cell surface via the interaction with deposited IgA1-immune complexes. In vitro, we found that collectin11 bound to IgA1-immune complexes in a dose-dependent but calcium-independent manner. Furthermore, deposited collectin11 initiated the activation of complement and accelerated the deposition of C3 on mesangial cells. CONCLUSIONS: In situ-produced collectin11 by mesangial cells might play an essential role in kidney injury in a subset of patients with IgA nephropathy through the induction of complement activation.

MicroRNA-21-5p participates in IgA nephropathy by driving T helper cell polarization.

BACKGROUND: Previous studies have revealed abnormal lymphocyte subsets in IgA nephropathy (IgAN). Some microRNAs have been reported to influence T helper differentiation. Here, we explored the underlying mechanism regarding how miRNAs regulate lymphocyte subsets in IgAN. METHODS: First, miRNA and mRNA profiles in PBMCs from IgAN patients and controls were obtained by next-generation sequencing and gene expression array. The target miRNAs and mRNAs were identified through combined analysis. Then, in an independent population, we detected the expression of target miRNA in CD3+ T cells and CD19+ B cells. Next, we detected T helper cell subgroups and plasma IgA1 levels in another independent population and analyzed the correlations between them. RESULTS: In total, 22 differentially expressed miRNAs were identified between IgAN patients and controls. Among them, microRNA-21-5p (miR-21) showed the highest expression, and SPRY1, SPRY2, and FASLG were chosen as miR-21 target genes. Then, we confirmed elevated miR-21 levels in CD3+ T cells of IgAN patients. Accordingly, decreased mRNA levels of SPRY1, SPRY2, and FASLG were found, and miR-21 showed a significant negative correlation with SPRY1 levels in CD3+ T cells of IgAN patients. Finally, we revealed that the proportion of Th17 cells was significantly elevated in IgAN patients and negatively correlated with SPRY1 expression. Furthermore, the proportion of Th17 cells showed a positive correlation trend with plasma IgA1 levels. CONCLUSIONS: Our results suggested that in IgAN, the upregulated miR-21 expression in T lymphocytes inhibited SPRY1 expression and thereby induced Th17 polarization, which might influence the characteristic feature of IgA1 overproduction in IgAN patients.

The potential role of mechanically sensitive ion channels in the physiology, injury, and repair of articular cartilage.

Biomechanical factors play an extremely important role in regulating the function of articular chondrocytes. Understanding the mechanical factors that drive chondrocyte biological responses is at the heart of our interpretation of cascade events leading to changes in articular cartilage osteoarthritis. The mechanism by which mechanical load is transduced into intracellular signals that can regulate chondrocyte gene expression remains largely unknown. The mechanically sensitive ion channel (MSC) may be one of its specific mechanisms. This review focuses on four ion channels involved in the mechanotransduction of chondrocytes, exploring their properties and the main factors that activate the associated pathways. The upstream and downstream potential relationships between the protein pathways were also explored. The specific biophysical mechanism of the chondrocyte mechanical microenvironment is becoming the focus of research. Elucidating the mechanotransduction mechanism of MSC is essential for the research of biophysical pathogenesis and targeted drugs in cartilage injury-related diseases.

Clinical Analysis of 1593 Patients with Infectious Endophthalmitis: A 12-Year Study at a Tertiary Referral Center in Western China / 中华医学杂志(英文版)

<p><b>Background</b>Infectious endophthalmitis is a severe ocular inflammation which can cause devastating visual loss. The aim of the study was to identify the demographic and clinical features of infectious endophthalmitis in Western China for better prophylaxis and treatment of this disease.</p><p><b>Methods</b>A.</p><p><b></b>retrospective, cross-sectional study was conducted based on the medical records of inpatients having infectious endophthalmitis in a tertiary referral center in Western China between 2005 and 2016.</p><p><b>Results</b>The common cause of infectious endophthalmitis was trauma (82.6%), endogenous (7.8%), ophthalmic surgery (6.9%), and corneal ulcer with perforation (2.7%). These four etiological groups differed in age, gender, enucleation rate, visual outcome, etc. The number of cases in the first 6 years accounted for 38.7% of the total collection, which in the second 6 years accounted for 61.3%. The etiology patterns were different between these two periods. Altogether 51.3% of patients received pars plana vitrectomy, 13.9% of patients underwent evisceration, and the remaining 34.8% received other treatments. Of the 670 cases that had culture results, 266 (39.7%) were culture positive and 177 (66.5%) were Gram-positive organisms, 64 (24.1%) were Gram-negative organisms, 11 (4.1%) had fungal infection, and 14 (5.3%) were infected by multiple pathogens.</p><p><b>Conclusions</b>There was an upward trend of the occurrence of infectious endophthalmitis in Western China for the past decade. The demographic and clinical characteristics of infectious endophthalmitis in Western China had its own characteristics and differed from those of developed countries. Here, open globe trauma was the most common cause of endophthalmitis, most traumatic endophthalmitis patients were male, and most of the injuries were work related, implicate that we should strengthen the education and application of ocular safety regulation specifically targeting the workplace.</p>