Park SY, et al. Allergy Asthma Immunol Res. 2018 Jul;10(4):387-396. https://doi.org/10.4168/aair.2018.10.4.387

Purpose: Different characteristics of airway microbiome in asthmatics may lead to differential immune responses, which in turn cause eosinophilic or neutrophilic airway inflammation. However, the relationships among these factors have yet to be fully elucidated. Methods: Microbes in induced sputum samples were subjected to sequence analysis of 16S rRNA. Airway inflammatory phenotypes were defined as neutrophils (>60%) and eosinophils (>3%), and inflammation endotypes were defined by levels of T helper (Th) 1 (interferon-gamma), Th2 (interleukin [IL]-5 and IL-13), Th-17 (IL-17), and innate Th2 (IL-25, IL-33, and thymic stromal lymphopoietin) cytokines, inflammasomes (IL-1 beta), epithelial activation markers (granulocyte-macrophage colony-stimulating factor and IL-8), and Inflammation (IL-6 and tumor necrosis factor-alpha) cytokines in sputum supernatants was assessed by enzyme-linked immunosorbent assay. Results: The numbers of operational taxonomic units were significantly higher in the mixed (n = 21) and neutrophilic (n = 23) inflammation groups than in the paucigranulocytic inflammation group (n = 19; p < 0.05). At the species level, Granulicatella adiacens, Streptococcus parasanguinis, Streptococcus pneumoniae, Veillonella rogosae, Haemophilus parainfluenzae, and Neisseria perflava levels were significantly higher in the eosinophilic inflammation group (n = 20), whereas JYGI/ s levels were significantly higher in the neutrophilic inflammation group compared to the other subtypes (P< 0.05). Additionally, IL-5 and IL-13 concentrations were correlated with the percentage of eosinophils (P < 0.05) and IL-13 levels were positively correlated with the read counts of Porphyromonas pasteri and V rogosae (P< 0.05). IL-1 beta concentrations were correlated with the percentage of neutrophils (P< 0.05). had a tendency to be positively correlated with the read count of JYGU_s (P= 0.095), and was negatively correlated with that of S. pneumoniae (P< 0.05). Conclusions: Difference of microbial patterns in airways may induce distinctive endotypes of asthma, which is responsible for the neutrophilic or eosinophilic inflammation in asthma.

Increasing evidence suggests that exosomes are involved in retinal cell degeneration, including their insufficient release; hence, they have become important indicators of retinopathies. The exosomal microRNA (miRNA), in particular, play important roles in regulating ocular and retinal cell functions, including photoreceptor maturation, maintenance, and visual function. Here, we generated retinal organoids (ROs) from human induced pluripotent stem cells that differentiated in a conditioned medium for 60 days, after which exosomes were extracted from ROs (Exo-ROs). Subsequently, we intravitreally injected the Exo-RO solution into the eyes of the Royal College of Surgeons (RCS) rats. Intravitreal Exo-RO administration reduced photoreceptor apoptosis, prevented outer nuclear layer thinning, and preserved visual function in RCS rats. RNA sequencing and miRNA profiling showed that exosomal miRNAs are mainly involved in the mitogen-activated protein kinase (MAPK) signaling pathway. In addition, the expression of MAPK-related genes and proteins was significantly decreased in the Exo-RO-treated group. These results suggest that Exo-ROs may be a potentially novel strategy for delaying retinal degeneration by targeting the MAPK signaling pathway.