Glucocorticosteroid dependent decrease in the activity of calcineurin in the peripheral blood mononuclear cells of patients with systemic lupus erythematosus

The role of protein kinase C isoenzymes in the pathogenesis of human autoimmune diseases

The physiological role of protein kinase C (PKC) enzymes in the immune system is presented briefly. From earlier publications of others data were collected how the defects of one/two isoenzymes of PKC system suggested their involvement in the pathogenesis of human autoimmune diseases. Our observations on the defects of seven PKC isoenzymes in the peripheral blood mononuclear cells (PBMC) demonstrate that these molecular impairments are not prerequisits of the pathogenesis of systemic lupus erythematosus (SLE), mixed connective tissue disease and Sjögren's syndrome. However, these defects can modulate the disease activity and symptoms especially in SLE by several pathways. The role of PKC system in other forms of autoimmune diseases is also very small. It was of note that we detected decreased expression of PKC isoenzymes in PBMC of a European white family with an X-linked genetic background showing seasonal undulations in the lupus patient and also in her healthy mother.

mRNAs in urinary nano-extracellular vesicles as potential biomarkers for non-invasive kidney biopsy

Urinary nano-extracellular vesicles (NVs), including exosomes and microvesicles, are considered potential biomarkers for kidney diseases using liquid biopsies. However, clinical application of urinary NVs has not yet been validated. In the present study, the levels of mRNAs in urinary NVs in animal models of kidney disease were assessed. Urine samples were collected from the animal models and urinary NVs were isolated by ultracentrifugation. Gene expression levels of kidney injury markers in urinary NVs and renal tissue were quantified by reverse transcription-quantitative PCR. The mRNA levels of desmin, a podocyte injury marker, in urinary NVs was markedly increased in the puromycin aminonucleoside (PAN) nephritis model, in parallel with enhanced desmin expression in kidney tissues. The expression of regulator of calcineurin 1 and the podocin to nephrin ratio (PNR) were also increased in the PAN nephritis model. Treatment with prednisolone mitigated these changes in gene expression as well as proteinuria. PNR, which is considered a predictive marker of glomerular dysfunction, in urinary NVs was highly correlated with urinary protein excretion (P<0.01). Furthermore, PNR in urinary NVs of Zucker diabetic fatty rats, a diabetic kidney disease model, was correlated with urinary albumin excretion (P<0.01). These results suggest that changes in mRNA levels of urinary NVs reflect the disease status of kidney tissues and their functional alterations. Collectively, mRNA analysis of urinary NVs may be used as a liquid biopsy tool for improved classification and performance of risk prediction to determine the severity of kidney diseases.

RNA-seq Analysis Reveals Unique Transcriptome Signatures in Systemic Lupus Erythematosus Patients with Distinct Autoantibody Specificities

Systemic lupus erythematosus (SLE) patients exhibit immense heterogeneity which is challenging from the diagnostic perspective. Emerging high throughput sequencing technologies have been proved to be a useful platform to understand the complex and dynamic disease processes. SLE patients categorised based on autoantibody specificities are reported to have differential immuno-regulatory mechanisms. Therefore, we performed RNA-seq analysis to identify transcriptomics of SLE patients with distinguished autoantibody specificities. The SLE patients were segregated into three subsets based on the type of autoantibodies present in their sera (anti-dsDNA+ group with anti-dsDNA autoantibody alone; anti-ENA+ group having autoantibodies against extractable nuclear antigens (ENA) only, and anti-dsDNA+ENA+ group having autoantibodies to both dsDNA and ENA). Global transcriptome profiling for each SLE patients subsets was performed using Illumina® Hiseq-2000 platform. The biological relevance of dysregulated transcripts in each SLE subsets was assessed by ingenuity pathway analysis (IPA) software. We observed that dysregulation in the transcriptome expression pattern was clearly distinct in each SLE patients subsets. IPA analysis of transcripts uniquely expressed in different SLE groups revealed specific biological pathways to be affected in each SLE subsets. Multiple cytokine signaling pathways were specifically dysregulated in anti-dsDNA+ patients whereas Interferon signaling was predominantly dysregulated in anti-ENA+ patients. In anti-dsDNA+ENA+ patients regulation of actin based motility by Rho pathway was significantly affected. The granulocyte gene signature was a common feature to all SLE subsets; however, anti-dsDNA+ group showed relatively predominant expression of these genes. Dysregulation of Plasma cell related transcripts were higher in anti-dsDNA+ and anti-ENA+ patients as compared to anti-dsDNA+ ENA+. Association of specific canonical pathways with the uniquely expressed transcripts in each SLE subgroup indicates that specific immunological disease mechanisms are operative in distinct SLE patients' subsets. This 'sub-grouping' approach could further be useful for clinical evaluation of SLE patients and devising targeted therapeutics.

Glucocorticosteroid therapy decreases CD14-expression and CD14-mediated LPS-binding and activation of monocytes in patients suffering from systemic lupus erythematosus

In order to study the possible action of glucocorticosteroids (GCS) on the CD14/Toll like receptor mediated activation of monocytes the CD14-expression, CD14-mediated LPS binding and activation of these cells of patients suffering from Systemic Lupus Erythematosus receiving no, low dose or pulse steroid treatment was studied. The CD14-expression was determined on whole blood monocytes by flow cytometry, while the LPS-binding of an FITC-LPS preparate and the LPS-induced TNFalpha secretion were tested on isolated monocytes. The CD14-dependent and -independent LPS-binding and activation were evaluated with the help of a blocking anti-CD14 mAb. Our results showed that the CD14-expression, CD14-dependent LPS-binding and activation were significantly inhibited by the in vivo applied pulse steroid therapy. In contrast, the CD14-independent LPS-binding and activation were not altered by the GCS treatment. Our data provide further in vivo evidence for a possible new way of GCS therapy is able to initiate its anti-inflammatory action.