The Role of Extracellular Vesicles in Systemic Lupus Erythematosus

Extracellular Vesicles in Renal Inflammatory Diseases: Revealing Mechanisms of Extracellular Vesicle-Mediated Macrophage Regulation

Renal inflammatory diseases are a group of severe conditions marked by significant morbidity and mortality. Extracellular vesicles (EVs), as facilitators of intercellular communication, have been recognized as pivotal regulators of renal inflammatory diseases, significantly contributing to these conditions by modulating immune responses among other mechanisms. This review highlights the intricate mechanisms through which EVs modulate macrophage-kidney cell interactions by regulating macrophages, the principal immune cells within the renal milieu. This regulation subsequently influences the pathophysiology of renal inflammatory diseases such as acute kidney injury and chronic kidney disease. Furthermore, understanding these mechanisms offers novel opportunities to alleviate the severe consequences associated with renal inflammatory diseases. In addition, we summarize the therapeutic landscape based on EV-mediated macrophage regulatory mechanisms, highlighting the potential of EVs as biomarkers and therapeutic targets as well as the challenges and limitations of translating therapies into clinical practice.

Advances in research on the mechanism of tsRNA action in tumours

tsRNA is a class of non-coding RNAs derived from mature or precursor tRNAs. In recent years, more and more studies have explored the correlation between tsRNAs and tumours. tsRNAs can affect the biological behaviours of tumour cells such as proliferation, apoptosis and metastasis by regulating gene expression, protein translation or post-transcriptional regulation. In this paper, we systematically review the production, biological function and research progress of tsRNA in tumour and discuss its prospects as biomarkers and therapeutic targets.

The Role of Extracellular Vesicles in Aging and Age-Related Disorders

A variety of molecular and cellular changes distinguish the multifaceted biological process of aging. Recent studies in this decade have demonstrated the essential role of extracellular vesicles (EVs) in the aging process. Mitochondrial malfunction and increased oxidative stress are major contributors for the aging process. This review investigates the role of EVs in intercellular communication, tissue regeneration, and inflammation in the context of aging. We also discuss the exosome and its utility to reduce oxidative stress, which is a key part of aging, as well as the possibility of using the exosomes (EVs) as anti-aging drugs. Changes in cargo composition can influence the aging phenotype and impact the functionality of cells and tissues. Additionally, the role of EVs in oxidative stress during the aging process addresses potential treatment strategies and the development of biomarkers for age-associated disorders. The review also highlighted the role of exosomes in providing antioxidant properties, which help reduce excessive reactive oxygen species (ROS) and strengthen cellular defenses against oxidative stress. Additionally, it emphasized the role of extracellular vesicles (EVs) in age-related pathologies, such as neurodegenerative diseases, cardiovascular disorders, and immunosenescence, offering insights into targeted interventions for promoting healthy aging. This article provides a comprehensive analysis of the current body of knowledge regarding the therapeutic effects of EVs on aging, with a particular emphasis on the implications of this emerging field of research and its relationship to oxidative stress.

Simultaneous Multi-miRNA Detection in Urinary Small Extracellular Vesicles Using Target-Triggered Locked Hairpin DNA-Functionalized Au Nanoprobes for Systemic Lupus Erythematosus Diagnosis

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by multiorgan involvement and complex clinical manifestations, leading to cumbersome diagnostic processes. MicroRNAs (miRNAs) in small extracellular vesicles (sEVs) have emerged as promising biomarkers for liquid biopsy. Herein, we constructed a simple multi-miRNA detection platform based on target-triggered locked hairpin DNA-functionalized Au nanoprobes (AuNP@LH) as a simple and noninvasive tool for the diagnosis and classification of SLE. The nanoprobes were prepared by modifying locked hairpin DNA designed for target miRNAs on gold nanoparticles. In the presence of target miRNAs, target-triggered hairpin assembly amplification was induced, and then fluorophore-labeled bolt DNA was released, resulting in a fluorescence signal responsive to miRNA concentration. Benefiting from the enzyme-free amplification strategy, the limits of detection (LOD) of three miRNA biomarkers for SLE were 19 pM for microRNA-146a, 66 pM for microRNA-29c, and 19 pM for microRNA-150. The proposed probes have been successfully applied to simultaneously detect multiple miRNAs in urinary sEVs from patients diagnosed with SLE and healthy controls, which exhibited good practicability in SLE diagnosis with the area under curve (AUC) of the receiver characteristic curve reaching 1.00. Furthermore, SLE patients with different disease severity can be differentiated with 81.2% accuracy. Predictably, with the advantages of low cost, rapidity, high sensitivity, and noninvasiveness, our multi-miRNA detection platform is a potential tool for multiple miRNA analysis and related clinical applications.

Lupus Nephritis from Pathogenesis to New Therapies: An Update

Lupus Nephritis (LN) still represents one of the most severe complications of Systemic Lupus Erythematosus (SLE) and a major risk factor for morbidity and mortality. However, over the last few years, several studies have paved the way for a deeper understanding of its pathogenetic mechanisms and more targeted treatments. This review aims to provide a comprehensive update on progress on several key aspects in this setting: pathogenetic mechanisms of LN, including new insight into the role of autoantibodies, complement, vitamin D deficiency, and interaction between infiltrating immune cells and kidney resident ones; the evolving role of renal biopsy and biomarkers, which may integrate information from renal histology; newly approved drugs such as voclosporin (VOC) and belimumab (BEL), allowing a more articulate strategy for induction therapy, and other promising phase III-immunosuppressive (IS) agents in the pipeline. Several adjunctive treatments aimed at reducing cardiovascular risk and progression of chronic renal damage, such as antiproteinuric agents, represent an important complement to IS therapy. Furthermore, non-pharmacological measures concerning general lifestyle and diet should also be adopted when managing LN. Integrating these therapeutic areas requires an effort towards a holistic and multidisciplinary approach. At the same time, the availability of an increasingly wider armamentarium may translate into improvements in patient's renal outcomes over the next decades.

Circulating extracellular vesicles in Systemic Lupus Erythematosus: physicochemical properties and phenotype

OBJECTIVE

This study aimed to identify the physicochemical and phenotypic characteristics of circulating Extracellular Vesicles (EVs) in the plasma of patients with SLE, with or without Lupus Nephritis (LN), and their potential utility as disease biomarkers.

METHODS

Plasma-circulating EVs were concentrated using differential centrifugation from adult female patients (n=38) who met the 'American College of Rheumatology/European Alliance of Associations for Rheumatology 2019' criteria for SLE diagnosis with (LN) or without LN (nLN), confirmed by renal biopsy. Controls (n=18) were healthy volunteers matched by gender and similar age. The structure, size and Energy Dispersion Spectrum (EDS) of EVs were observed by electron microscopy. The surface charge and size distribution were evaluated using dynamic light scattering. The counts and phenotype of EVs from patients (SLE-EVs) and controls (Ctrl-EVs) were obtained using flow cytometry. Non-parametric statistical tests and exploratory analysis of multiple variables were performed. The discriminatory power of some variables as potential biomarkers of the disease was also evaluated.

RESULTS

Circulating EVs were heterogeneous in morphology and size, but SLE-EVs reached larger diameters than Ctrl-EVs (p<0.0001). Small SLE-EVs and large SLE-EVs were increased compared with Ctrl-EV (p<0.0001 and p<0.05, respectively). Likewise, patients with SLE (LN or nLN) had higher concentrations of large EVs compared with controls (p<0.001 and p<0.0001, respectively). SLE-EVs showed a different EDS (p<0.001) and were less electronegative (p<0.0001) than Ctrl-EVs. EV-CD45+, EV-CD14+ and EV-IgM+ were more frequent in patients with SLE compared with controls (p<0.001, p<0.05 and p<0.001, respectively). The concentrations of large EVs and EV-IgM+ allowed better discrimination of patients from controls.

CONCLUSIONS

Plasma-circulating EVs from patients with SLE with and without nephritis are increased in peripheral blood and have different physicochemical properties than controls. Characteristics of EVs such as larger size and the presence of IgM on the surface could help discriminate patients from controls.

Urinary exosome tsRNAs as novel markers for diagnosis and prediction of lupus nephritis

Objective

Lupus nephritis (LN) is one of the most severe organ manifestations of systemic lupus erythematosus (SLE). Early identification of renal disease in SLE is important. Renal biopsy is currently recognized as the gold standard for diagnosing LN, however, it is invasive and inconvenient for dynamic monitoring. Urine has been considered more promising and valuable than blood in identifying inflamed kidney tissue. Here, we determine whether the signatures of tRNA-derived small noncoding RNA (tsRNA) in urinary exosomes can serve as novel biomarkers for the diagnosis of LN.

Methods

tsRNA sequencing was performed in exosome extracted from pooled urine of 20 LN patients and 20 SLE without LN, and the top 10 upregulated tsRNAs were screened as candidate markers of LN. The candidate urinary exosomal tsRNAs were primarily elected by TaqMan probe-based quantitative reverse transcription-PCR (RT-PCR) in 40 samples (20 LN and 20 SLE without LN) in the training phase. In the validation phase, selected tsRNAs from the training phase were further confirmed in a larger cohort (54 LN patients and 39 SLE without LN). Receiver operating characteristic curve (ROC) analysis was conducted to evaluate the diagnostic efficacy.

Results

Upregulated levels of tRF3-Ile-AAT-1 and tiRNA5-Lys-CTT-1 in the urinary exosomes were observed in LN compared with SLE without LN (P < 0.0001 and P < 0.001) and healthy controls (P < 0.01 and P < 0.01), with the area under the curve (AUC) of 0.777 (95% CI: 0.681-0.874, sensitivity 79.63%, specificity 66.69%) and 0.715 (95% CI: 0.610-0.820, sensitivity 66.96%, specificity 76.92%) for discriminating LN from SLE without LN patients. SLE patients with mild activity and moderate to severe activity had higher levels of urinary exosome derived tRF3-Ile AAT-1 (P = 0.035 and P < 0.001) and tiRNA5-Lys-CTT-1 (P = 0.021 and P < 0.001) compared with patients with no activity. Moreover, bioinformatics analysis revealed that both of the tsRNAs regulate the immune process by modulating metabolism and signal pathway.

Conclusion

In this study, we demonstrated that urinary exosome tsRNAs can be served as noninvasive biomarkers for the efficient diagnosis and prediction of nephritis in SLE.

Regulation of Extracellular Vesicle-Mediated Immune Responses against Antigen-Specific Presentation

Extracellular vesicles (EVs) produced by various immune cells, including B and T cells, macrophages, dendritic cells (DCs), natural killer (NK) cells, and mast cells, mediate intercellular communication and have attracted much attention owing to the novel delivery system of molecules in vivo. DCs are among the most active exosome-secreting cells of the immune system. EVs produced by cancer cells contain cancer antigens; therefore, the development of vaccine therapy that does not require the identification of cancer antigens using cancer-cell-derived EVs may have significant clinical implications. In this review, we summarise the molecular mechanisms underlying EV-based immune responses and their therapeutic effects on tumour vaccination.

The state of the art of extracellular vesicle research in protozoan infection

Protozoan diseases seriously affect the health of human beings, livestock and poultry and lead to high economic and medical costs. Extracellular vesicles (EVs) are membranous structures formed through biological processes that play important roles in immune regulation. Studies have shown that parasites transmit information to hosts through EVs to modulate host immune responses. The major roles played by EVs released from parasites involve facilitating parasitization of the host. In this review, we discuss relevant recently obtained data on EVs secreted by different kinds of protozoa, including their molecular mechanisms, and discuss the roles played by EVs in the occurrence and development of parasitic diseases.

Recent advances on drug delivery nanoplatforms for the treatment of autoimmune inflammatory diseases

As one of the current research hotspots, drug release nanoplatforms have great potential in the treatment of autoimmune inflammatory diseases.