Background: Patients with spondyloarthritis (SpA)/HLA-B27-associated acute anterior uveitis (AAU) experience recurring acute flares, which pose significant visual and financial challenges. Despite established links between SpA and HLA-B27-associated AAU, the exact mechanism involved remains unclear, and further understanding is needed for effective prevention and treatment. Methods: To investigate the acute pathogenesis of SpA/HLA-B27-associated AAU, Mendelian randomization (MR) and single-cell transcriptomic analyses were employed. The MR incorporated publicly available protein quantitative trait locus data from previous studies, along with genome-wide association study data from public databases. Causal relationships between plasma proteins and anterior uveitis were assessed using two-sample MR. Additionally, colocalization analysis was performed using Bayesian colocalization. Single-cell transcriptome analysis utilized the anterior uveitis dataset from the Gene Expression Omnibus (GEO) database. Dimensionality reduction, clustering, transcription factor analysis, pseudotime analysis, and cell communication analysis were subsequently conducted to explore the underlying mechanisms involved. Results: Mendelian randomization analysis revealed that circulating levels of AIF1 and VARS were significantly associated with a reduced risk of developing SpA/HLA-B27-associated AAU, with AIF1 showing a robust correlation with anterior uveitis onset. Colocalization analysis supported these findings. Single-cell transcriptome analysis showed predominant AIF1 expression in myeloid cells, which was notably lower in the HLA-B27-positive group. Pseudotime analysis revealed dendritic cell terminal positions in differentiation branches, accompanied by gradual decreases in AIF1 expression. Based on cell communication analysis, CD141+CLEC9A+ classic dendritic cells (cDCs) and the APP pathway play crucial roles in cellular communication in the Spa/HLA-B27 group. Conclusions: AIF1 is essential for the pathogenesis of SpA/HLA-B27-associated AAU. Myeloid cell differentiation into DCs and decreased AIF1 levels are also pivotal in this process.
14 November 2022 in Frontiers in Bioengineering and Biotechnology
With continued expansion of the aged population, the number of patients with retinal degeneration, which is a leading cause of vision loss worldwide, is growing. Stem cell therapies offer hope for regeneration and repair of damaged retinal tissue. Recent reports have highlighted stem cell-derived paracrine mediators, such as exosomes, which appear to exert a therapeutic benefit similar to their cell of origin and do not carry the risk of cell transplantation. One speculated role is that exosomes likely mediate intercellular communication and material exchange. This review depicts the molecular mechanisms underlying exosome-based therapy, especially in retina degeneration diseases. In the future, the use of stem cell-derived exosomes could be considered a novel and cell-free therapeutic strategy in regenerative medicine.
Uveal melanoma (UM) is adults’ most common primary intraocular malignant tumor. It has been observed that 40% of patients experience distant metastasis during subsequent treatment. While there exist multigene models developed using machine learning methods to assess metastasis and prognosis, the immune microenvironment’s specific mechanisms influencing the tumor microenvironment have not been clarified. Single-cell transcriptome sequencing can accurately identify different types of cells in a tissue for precise analysis. This study aims to develop a model with fewer genes to evaluate metastasis risk in UM patients and provide a theoretical basis for UM immunotherapy. RNA-seq data and clinical information from 79 μm patients from TCGA were used to construct prognostic models. Mechanisms were probed using two single-cell datasets derived from the GEO database. After screening for metastasis-related genes, enrichment analysis was performed using GO and KEGG. Prognostic genes were screened using log-rank test and one-way Cox regression, and prognostic models were established using LASSO regression analysis and multifactor Cox regression analysis. The TCGA-UVM dataset was used as internal validation and dataset GSE22138 as external validation data. A time-dependent subject work characteristic curve (time-ROC) was established to assess the predictive ability of the model. Subsequently, dimensionality reduction, clustering, pseudo-temporal analysis and cellular communication analysis were performed on GSE138665 and GSE139829 to explore the underlying mechanisms involved. Cellular experiments were also used to validate the relevant findings. Based on clinical characteristics and RNA-seq transcriptomic data from 79 samples in the TCGA-UVM cohort, 247 metastasis-related genes were identified. Survival models for three genes (SLC25A38, EDNRB, and LURAP1) were then constructed using lasso regression and multifactorial cox regression. Kaplan-Meier survival analysis showed that the high-risk group was associated with poorer overall survival (OS) and metastasis-free survival (MFS) in UM patients. Time-dependent ROC curves demonstrated high predictive performance in 6 m, 18 m, and 30 m prognostic models. Cell scratch assay showed that the 24 h and 48 h migration rates of cells with reduced expression of the three genes were significantly higher than those of the si-NC group. CD8 + T cells may play an important role in tumour metastasis as revealed by immune infiltration analysis. An increase in the percentage of cytotoxic CD8 + T cells in the metastatic high-risk group was found in the exploration of single-cell transcriptome data. The communication intensity of cytotoxic CD8 was significantly enhanced. It was also found that the CD8 + T cells in the two groups were in different states, although the number of CD8 + T cells in the high-risk group increased, they were mostly in the exhausted and undifferentiated state, while in the low-risk group, the CD8 + T cells were mostly in the functional state. We developed a precise and stable 3-gene model to predict the metastatic risk and prognosis of patients. CD8 + T cells exhaustion in the tumor microenvironment play a crucial role in UM metastasis.
Nemonoxacin is a novel non-fluorinated quinolone with strong antibacterial efficacy, but data of its effect on acute exacerbations of chronic obstructive pulmonary disease (AECOPD) is rare. This study was conducted to compare the efficacy of oral nemonoxacin with moxifloxacin in AECOPD outpatients. In this retrospective observational study, a total of 101 AECOPD outpatients initially treated with nemonoxacin or moxifloxacin from July 2021 to March 2022 were enrolled. We collected COPD assessment test (CAT), Transition Dyspnea Indices (TDI) scores, and exacerbations information during 24 weeks follow-up from the electronic medical records. Kaplan–Meier curve was used to analyze the time to the next moderate/severe exacerbation. Compared to the moxifloxacin group, changes in CAT scores and TDI scores were significantly higher in the nemonoxacin group, and the nemonoxacin group also had a greater probability to reach the minimal clinically important difference of CAT (71.40% vs. 97.80%, p < 0.01) and TDI (40.50% vs. 60.00%, p < 0.05) at week 4. Despite no significant difference in the incidence of exacerbations between two groups, patients treated with nemonoxacin had a significantly prolonged time to next moderate/severe exacerbation than those with moxifloxacin (p < 0.05). Nemonoxacin achieved a better symptomatic improvement and a prolonged interval to next moderate/severe exacerbation for AECOPD outpatients.
Docetaxel (DTX) is a highly effective anti-tumor drug frequently used in clinical practice. Previous reports indicated that complications after DTX therapy could be related to retinal pigment epithelial (RPE) cell dysfunction, although no direct reports of this relationship have been published. In this study, human embryonic stem cell–derived RPE (hESC-RPE) cells were used to explore the effects of DTX on their morphology, viability, apoptosis, proliferation, and cell cycle. We also searched for DTX residue in these cells. DTX had a time- and concentration-dependent inhibitory effect on hESC-RPE cell viability, and the cells only survived after 24 h of stimulation with 0.1 mg/mL of DTX. Following drug withdrawal, the cell morphology continued to change, and hESC-RPE cell damage was observed. High-performance liquid chromatography/mass spectrometry showed that some unmetabolized DTX remained in hESC-RPE cells after the 48 and 120 h DTX treatments. Flow cytometry and immunofluorescence revealed that DTX significantly enhanced apoptosis, and the Cell Counting Kit-8 assay and flow cytometry indicated that DTX inhibited cell proliferation and blocked the cell cycle. These results suggest that DTX has a direct cytotoxic effect on hESC-RPE cells. Thus, RPE cell damage after DTX treatment may present an important safety problem that could potentially limit the application of this drug in clinical practice. The findings of this study suggest that clinicians should weigh the benefits of DTX versus the risks of ocular adverse reactions rationally. Timely diagnostic evaluation and drug withdrawal will be conducive to the recovery of patients' visual acuity.
24 September 2022 in Biochemical and Biophysical Research Communications