Retinal degenerative diseases are a group of blinding ocular disorders characterized by progressive and irreversible loss of retinal neural cells. They mainly include age-related macular degeneration and retinitis pigmentosa. At present, there are no curative clinical therapies capable of reversing the disease course. Patients have poor long-term visual prognosis, imposing a heavy public-health burden on families and society. Mesenchymal stem cell(MSC)-derived exosomes, as a novel cell-free therapeutic vector, have emerged as a research hotspot due to their low immunogenicity, no tumorigenic risk, and excellent tissue barrier penetration ability. This review systematically summarizes the core mechanisms of MSC-derived exosomes in regulating immune inflammation, inhibiting apoptosis, and promoting retinal neuroprotection and structural/functional recovery via miRNA and tsRNA, compares the efficacy differences and existing controversies among exosomes from different sources, and outlines the advances in intraocular delivery technologies and engineering modification strategies. Combined with preclinical and clinical data, the current bottlenecks and safety evidence for clinical translation were objectively described. Meanwhile, in view of the heterogeneity among existing studies, this review proposes future directions including standardized preparation and the establishment of efficacy evaluation systems, so as to provide theoretical references for the development of novel therapeutic strategies for retinal degenerative diseases.

Objective To investigate whether the hyper-reactivity of monocytes from the patients with primary biliary cirrhosis (PBC) to LPS and Poly I ∶ C was associated with miR-146a.Methods Peripheral blood mononuclear cells from PBC patients and healthy controls were stimulated with 10 μg/ml of LPS or Poly I ∶ C.The levels of IL-1 β,IL-6,TNF-α and IFN-α in the culture medium were detected by ELISA.The relative expressions of miR-146a,miR-21,let-7e,miR-155 and miR-125b were detected by RT-PCR.The regulatory role of miR-146a on the production of inflammatory factors in LPS or Poly I ∶ C stimulated THP-1 cells was studied by gain-and-loss function assay.Results The up-regulation of miR146a,which was induced by both LPS or Poly I ∶ C,was impaired in the monocytes from PBC patients.The production of LPS or Poly I ∶ C induced inflammatory factor,could be enhanced by miR-146a down-regulation.Conclusion The hyper-reactivity of monocytes from PBC patients to LPS and Poly I ∶ C was associated with miR-146a.

MicroRNAs (miRNAs) are a new class of noncoding RNA which regulate gene expression at post-transcription level.It is believed that miRNAs are widely involved in the pathological and physiological processes,including the proliferation,development,differentiation and apoptosis regulation.

Objective To investigate the association between IL-22 and the pathogenesis of coronary artery atherosclerosis(AS).Methods The relative expression of IL-22 mRNA in PBMC from 30 AS patients and 8 patients without any signs of coronary artery stenosis was detected by RT-PCR.Serum IL-22 levels of 22 patients without any signs of coronary artery stenosis and 79 AS patients were detected by ELISA.CRL-1730 cells(human umbilical vein endothelial cells) were stimulated with oxidized low density lipoprotein (ox-LDL) at different dosage for 24 h,and the expression of IL-22R1 was detected by flowcytometry.The proliferation ability of CRL-1730 cells treated with IL-22(20 ng/ml) and/or ox-LDL(100 μg/ml)was measured by MTS assay,and the expression of basic fibroblast growth factor(bFGF) was detected by RTPCR and ELISA.Results Decreased IL-22 expression in PBMC and serum was observed as worsen of AS.The expression of IL-22R1 in ox-LDL treated CRL-1730 cells was increased in dose dependent manner.OxLDL decreased proliferation ability,as well as bFGF expression and releasing,of CRL-1730 cells.This effect of ox-LDL was partially rescued by IL-22.Conclusion IL-22 may have anti-atherosclerosis effect.This effect may be mediated by regulating bFGF expression and endothelial cells proliferation ability in the presence of IL-22.

Objective To investigate the increased expression of microRNA-146a(miR-146a) in peripheral blood mononuclear cells (PBMC) of patients with chronic immune thrombocytopenic purpura (ITP) and its clinical significance. Methods Twenty-eight patients with chronic ITP and 28 healthy controls matched with age and gender were enrolled in this study. Fluorescent quantitative PCR reaction was used to detect the relative expression of miR-146a in their PBMC. The serum concentration of TNF-α, IL-2,IL-1 β and IFN-γ were measured by ELISA. CCK-8 method was used to detect the proliferation ability of PBMC , which transfected with miR-146a mimics or inhibitor and then stimulated with platelet . Results The relative expression of miR-146a in ITP patients was higher than that of healthy controls. The increased expression of miR-146a was negatively correlated with the serum TNF-α, IL-2 and IFN-γ. The PBMC transfected with miR-146a mimics had reduced expression of IL-2 and proliferation when stimulated with platelet.In contrast, the opposite effect was observed with the miR-146a inhibitors transfection. Conclusion MiR146a was involved in the pathogenesis of chronic ITP by controlling IL-2 production and PBMC proliferation.Thus, it may be a potential therapy target for chronic ITP.

Objective To detect the expression of IL-27 in PBC (primary biliary cirrhosis)patients and the possible involvement of IL-27 signal pathway in PBC. Methods The gene transcription and protein expression levels of IL-27 in patients with PBC, chronic hepatitis B(CHB) group and healthy controls(HC) were measured by real-time PCR, ELISA, flow cytometry and immunohistochemistry. AST,ALP, ALT, TBIL, GGT were determined and their correlation with IL-27 was also analyzed. Results IL-27 was significantly elevated in patients with PBC and IL-27 is present in the liver tissues of patients with PBC. Expression of IL-27 on CD4+T cells was increased in patients with PBC(72.40% ±6.22% ) and CHB(59.40% ± 7.03%) compared with HC(1.70%±0.55%,P＜0.01). Expression of IL-27 protein was increased in patients with PBC [( 126.25 ± 36.00 ) pg/ml] compared with CHB [( 51.81 ± 23.30 )pg/ml, P ＜ 0. 01] and HC[(34.19 ± 9.70) pg/ml, P ＜ 0.01], and it was positively correlated with GGT( r = 0.554, P＜0.01) and TBIL (r = 0.559,P＜0.01), but no correlation with ALT, AST, ALP.Conclusion These facts indicated the key role of IL-27 in the immune inflammatory reaction in patients with PBC.