Immune-mediated kidney disease in 2017: Progress in mechanisms and therapy for immunological kidney disease

Clinical phenotypes of comorbidities in end-stage knee osteoarthritis: a cluster analysis

OBJECTIVES

Comorbidities, as components of these heterogeneous features, often coexist with knee osteoarthritis, and are particularly prevalent in end-stage knee osteoarthritis. Here, we attempted to identify the different clinical phenotypes of comorbidities in patients with end-stage knee osteoarthritis by cluster analysis.

METHODS

A total of 421 inpatients diagnosed with end-stage knee osteoarthritis who underwent inpatient surgery were included in this cross-sectional study. 23 demographic, comorbidity, inflammatory immune and evaluation scale variables were collected. Systematic clustering after factor analysis and separate two-step cluster analysis were performed for individual comorbidity variables and all variables, respectively, to objectively identify the different clinical phenotypes of the study patients.

RESULTS

Four clusters were finally identified. Cluster 1 had the largest proportion of obese patients (93.8%) and hypertension was common (71.2%). Almost all patients in cluster 2 were depressed (95.8%) and anxiety disorders (94.7%). Cluster 3 combined patients with isolated end-stage knee osteoarthritis and a few comorbidities. Cluster 4 had the highest proportion of patients with rheumatoid arthritis (58.8%).

CONCLUSIONS

Patients with end-stage knee osteoarthritis may be classified into four different clinical phenotypes: "isolated end-stage knee osteoarthritis"; "obesity + hypertension"; "depression + anxiety"; and "rheumatoid arthritis", which may help guide individualized patient care and treatment strategies.

Traditional Chinese medicine for the treatment of immune-related nephropathy: A review

Immune-related nephropathy (IRN) refers to immune-response-mediated glomerulonephritis and is the main cause of end-stage renal failure. The pathogenesis of IRN is not fully understood; therefore, treatment is challenging. Traditional Chinese medicines (TCMs) have potent clinical effects in the treatment of the IRN conditions immunoglobulin A nephropathy, lupus nephropathy, and diabetic nephropathy. The underlying mechanisms mainly include its inhibition of inflammation; improvements to renal interstitial fibrosis, oxidative stress, autophagy, apoptosis; and regulation of immunity. In this review, we summarize the clinical symptoms of the three IRN subtypes and the use of TCM prescriptions, herbs, and bioactive compounds in treating IRN, as well as the potential mechanisms, intending to provide a reference for the future study of TCM as IRN treatments.

Expression of CCL2, FOS, and JUN May Help to Distinguish Patients With IgA Nephropathy From Healthy Controls

Background

IgA nephropathy (IgAN), the most common type of glomerulonephritis worldwide, can only be diagnosed mainly by renal biopsy owing to lack of effective biomarkers. It is urgent to explore and identify the potential diagnostic biomarkers through assessing the gene expression profiles of patients with IgAN.

Methods

Two datasets were obtained from the Gene Expression Omnibus (GEO) database, including GSE115857 (55 IgAN, 7 living healthy donors) and GSE35487 (25 IgAN, 6 living healthy donors), then underwent differentially expressed genes (DEGs) and function enrichment analyses utilizing R packages. The common gene list was screened out between DEGs and immune-associated genes by Venn diagram, then performed gene-gene interaction, protein-protein interaction (PPI) and function enrichment analyses. Top three immune-associated hub genes were selected by Maximal Clique Centrality (MCC) method, then the expression and diagnostic value of these hub genes were determined. Consensus clustering algorithm was applied to conduct the unsupervised cluster analysis of the immune-associated hub gene list in IgAN. Finally, the Nephroseq V5 tool was applied to identify the expression level of CCL2, FOS, JUN in kidney diseases, as well as the correlation between CCL2, FOS, JUN expression and renal function in the patients with IgAN.

Results

A total of 129 DEGs were obtained through comparing IgAN with healthy controls via the GSE115857 and GSE35487 datasets. Then, we screened out 24 immune-associated IgAN DEGs. CCL2, JUN, and FOS were identified as the top three hub genes, and they were all remarkably downregulated in IgAN. More importantly, CCL2, JUN, and FOS had a high accuracy [area under the curve (AUC) reached almost 1] in predicting IgAN, which could easily distinguish between IgAN patients and healthy individuals. Three distinct subgroups of IgAN were determined based on 24 immune-associated DEGs, with significant differences in the expression of CCL2, JUN, and FOS genes. Finally, CCL2, FOS, JUN were manifested a meaningful association with proteinuria, glomerular filtration rate (GFR), and serum creatinine level.

Conclusion

In summary, our study comprehensively uncovers that CCL2, JUN, and FOS may function as promising biomarkers for diagnosis of IgAN.

Efficacy of Glucocorticoids and Glucocorticoid-Induced Hyperglycaemia in Renal Disease: A Meta-Analysis of Randomized Controlled Trials

Background

Glucocorticoids are the most effective anti-inflammatory and immunosuppressive drugs used to treat patients with renal disease. This study pooled the current evidence of the efficacy of Glucocorticoids and Glucocorticoid-induced hyperglycaemia in renal disease.

Methods

We conducted a systematic literature search on PubMed, Cochrane Central, and Web of Science for relevant randomized controlled trials (RCTs) up to September 1, 2021. The meta-analysis, sensitivity analysis and bias analysis were performed using Review Manager 5. 3.

Results

In this study, seven RCTs with 797 patients were included in our analysis. The analysis revealed that glucocorticoids had a certain alleviating effect on the reduction of renal function. (risk ratio [RR] 0.49 95% confidence interval [Cl] 0. 28 to 0.85, p =0.01) and reduction of proteinuria (weight mean difference [WMD] -0.43; 95% CI -0.57 to-0.28) when compared with the control group. Patients receiving glucocorticoids therapy did not have an increased risk of developing new-onset diabetes mellitus or impaired glucose tolerance. (RR 3.76 95% CI 0.54 to 26.10, p =0.18). For other safety outcomes, glucocorticoids therapy did not increase risk of respiratory infections (RR 1.63, 95% CI 0. 69to3. 89, p =0.27) and Gastrointestinal SAEs is relatively controversial (RR 1.10, 95% CI 0.32 to 3.79, p =0.88). Discussion. In conclusion, current clinical evidence indicates that glucocorticoids is efficacious and safe to renal disease compared with control. Further research comparing long-term glucocorticoids use is needed.

Renal progenitor cells modulated by angiotensin II receptor blocker (ARB) medication and differentiation towards podocytes in anti-thy1.1 nephritis

Background

Mesangial proliferative glomerulonephritis (MsPGN) is an epidemic disease with increasing occurrence. As important as mesangial cells, podocytes are key innate cells for MsPGN prognosis and recovery. Renal progenitor cells, located at the urinary pole (UP) of Bowman’s capsule (BC), could alleviate kidney injury through their capacity to differentiate into podocytes.

Methods

Seventy-two male rats were categorized randomly into the sham (n=24), untreated Thy-1 (n=24) and losartan-treated (n=24) groups. We administered vehicle or losartan (50 mg/kg by gavage) daily to treat rats with anti-thy1.1 nephritis, an ideal model to simulate human MsPGN. Two weeks after the intravenous injection of antibody, urinary protein and blood samples were analyzed, pathological changes were examined, the number of podocytes was determined, and renal progenitor cells were studied.

Results

Anti-thy1.1 nephritis was significantly alleviated after losartan treatment, as reported previously and as expected. Compared with the untreated Thy-1 group, the number of podocytes in the losartan group increased, and the area of renal progenitor cells significantly increased. The protein expression of components of the p-ERK pathway was determined during the development of renal progenitor cells differentiating into podocytes.

Conclusions

The data in this paper show the direct glomerular cell action of angiotensin II receptor blocker (ARB) treatment in improving outcomes in anti-thy1.1 nephritis. The positive effects of ARB medication on anti-thy1.1 nephritis were due to an increase in the number of renal epithelial progenitor cells (defined as PECs that expressed only stem cell markers without podocyte proteins).

Identification and external validation of IgA nephropathy patients benefiting from immunosuppression therapy

BACKGROUND

Although IgA nephropathy (IgAN), an immune-mediated disease with heterogeneous clinical and pathological phenotypes, is the most common glomerulonephritis worldwide, it remains unclear which IgAN patients benefit from immunosuppression (IS) therapy.

METHODS

Clinical and pathological data from 4047 biopsy-proven IgAN patients from 24 renal centres in China were included. The derivation and validation cohorts were composed of 2058 and 1989 patients, respectively. Model-based recursive partitioning, a machine learning approach, was performed to partition patients in the derivation cohort into subgroups with different IS long-term benefits, associated with time to end-stage kidney disease, measured by adjusted Kaplan-Meier estimator and adjusted hazard ratio (HR) using Cox regression.

FINDINGS

Three identified subgroups obtained a significant IS benefits with HRs ≤ 1. In patients with serum creatinine ≤ 1·437 mg/dl, the benefits of IS were observed in those with proteinuria > 1·525 g/24h (node 6; HR = 0·50; 95% CI, 0·29 to 0·89; P = 0·02), especially in those with proteinuria > 2·480 g/24h (node 8; HR =  0·23; 95% CI, 0·11 to 0·50; P <0·001). In patients with serum creatinine > 1·437 mg/dl, those with high proteinuria and crescents benefitted from IS (node 12; HR = 0·29; 95% CI, 0·09 to 0·94; P = 0·04). The treatment benefits were externally validated in the validation cohort.

INTERPRETATION

Machine learning could be employed to identify subgroups with different IS benefits. These efforts promote decision-making, assist targeted clinical trial design, and shed light on individualised treatment in IgAN patients.

FUNDING

National Key Research and Development Program of China (2016YFC0904103), National Key Technology R&D Program (2015BAI12B02).