Extracellular vesicles derived from Spirometra erinaceieuropaei plerocercoids inhibit activation of murine macrophage RAW264.7 cells.

Parasitic helminths modify host immune reactions to promote long-term parasitism. We previously purified a glycoprotein, plerocercoid-immunosuppressive factor (P-ISF), from the excretory/secretory products of Spirometra erinaceieuropaei plerocercoids and reported its cDNA and genomic DNA sequences. In this study, we isolated extracellular vesicles (EVs) from the excretory/secretory products of S. erinaceieuropaei plerocercoids and found that they suppressed the production of nitric oxide and the gene expression of tumor necrosis factor-α, interleukin-1ß, and interleukin-6 in lipopolysaccharide-stimulated macrophages. EVs are membrane-bound vesicles 50-250 nm in diameter and are localized in the whole bodies of plerocercoids. EVs from plerocercoids encapsulate a variety of unidentified proteins and microRNAs (miRNAs), which are non-coding RNAs that play essential roles in post-transcriptional gene regulation. The miRNAs of the EVs were analyzed, and 334,137 sequencing reads were mapped to the genomes of other organisms. A total of 26 different miRNA families were identified, including miR-71, miR-10-5p, miR-223, and let-7-5p, which have been reported to have immunosuppressive effects. We confirmed that P-ISF was present in the supernatant but not in the EVs by western blotting with an anti-P-ISF antibody. These results suggest that S. erinaceieuropaei plerocercoids suppress host immunity by releasing P-ISF and EVs.

Social participation patterns and the incidence of functional disability: The Japan Gerontological Evaluation Study.

AIM: To examine whether patterns of social participation vary in their associations with functional disability. METHODS: Data from 44 978 participants (22 750 men and 22 228 women) who participated in the 2010 Japan Gerontological Evaluation Study were analyzed; a study of those aged ≥65 years from 23 municipalities in eight prefectures. Social participation information was obtained at baseline with an eight-item questionnaire. Incidence of functional disability from 2010 to 2013 was defined as a new certification of eligibility for municipal public long-term care insurance. Social participation patterns were analyzed using exploratory factor analysis and participants were classified into quartiles of factor scores of social participation patterns. A competing risk model was used to calculate the hazard ratios and 95% confidence intervals for the incidence of functional disability in 3 years of follow-up. RESULTS: Two social patterns were identified: sports groups/clubs and hobby groups, and political groups/organizations and industry/trade associations. For both patterns, compared with participants in the lowest quartile, participants in the highest quartile were more likely to be male, college educated, high-income and current drinkers. Both patterns were associated with reduced incidence of functional disability (adjusted hazard ratios for top quartile of sports and hobby pattern: 0.66, 95% confidence interval: 0.59, 0.74; for political and industry/trade pattern: 0.81, 95% confidence interval: 0.72, 0.90; P for trend <0.001 for both). CONCLUSIONS: Those whose social participation patterns were characterized by frequent participation in sports groups/clubs and hobby groups or political groups/organizations and industry/trade associations were less likely to develop a functional disability. Geriatr Gerontol Int 2020; 20: 765-772.