Clinical efficacy and mechanism of mesenchymal stromal cells in treatment of COVID-19.

Coronavirus disease 2019 (COVID-19) is a highly infectious epidemic disease that has seriously affected human health worldwide. To date, however, there is still no definitive drug for the treatment of COVID-19. Cell-based therapies could represent a new breakthrough. Over the past several decades, mesenchymal stromal cells (MSCs) have proven to be ideal candidates for the treatment of many viral infectious diseases due to their immunomodulatory and tissue repair or regeneration promoting properties, and several relevant clinical trials for the treatment of COVID-19 have been registered internationally. Herein, we systematically summarize the clinical efficacy of MSCs in the treatment of COVID-19 based on published results, including mortality, time to symptom improvement, computed tomography (CT) imaging, cytokines, and safety, while elaborating on the possible mechanisms underpinning the effects of MSCs, to provide a reference for subsequent studies.

High Acceptance of HIV Self-testing Among PrEP Recipients before COVID-19 Era: A Cross-sectional Analysis from PrEP Demonstration Project of MSM in China (preprint)

Background: Many Pre-exposure prophylaxis (PrEP) users have difficulty attending the quarterly facility-based HIV testing, which leads to the potential risk of drug resistance in the context of breakthrough infection with low drug compliance. We explored the acceptance of HIV self-testing (HIVST) service among PrEP recipients. Methods: MSM were recruited for the PrEP demonstration in four major cities in China from December 2018 to September 2019, provided with regimens of both daily and on-demand PrEP. Facility-based HIV testing was provided quarterly at clinic visits. Previous HIV testing history and acceptance of free HIVST kits to use between each quarterly clinic visit was collected. Correlates of levels of acceptance were analysed using multivariable ordinal logistic regression. Results: We recruited 1,222 MSM. among which 48.5% preferred daily PrEP and 51.5% preferred on-demand PrEP. There was 26.8% (321/1222) had never been to any facility-based HIV testing previously, and the self-reported major reason was that they had already routinely used HIVST. A quarter of the participants (74.5%, 910/1222) had used HIVST previously. There were 1184 MSM (96.9%) accepted to use HIVST between each quarterly clinic visits during PrEP usage, composing 947 ( 77.5%) very willing to, 237（19.4%）willing to, 29 (2.4%) unwilling to, and 9 (0.7%) very unwilling to. Participants preferred daily PrEP (vs. on-demand PrEP, aOR=1.8, 95% CI:1.3-2.4) and had less than 2 times of facility-based HIV testing in the past year (vs. ³2, aOR=1.4,95% CI:1.1-1.9) were more likely to have higher level of acceptance of HIVST.Conclusions: MSM had high acceptance of HIVST, especially among those preferred daily PrEP and with less facility-based HIV testing in the previous year. Offering HIVST services PrEP recipients is feasible and necessary. Above result is of great significance for promoting HIVST among PrEP users during COVID-19, improving awareness of their HIV infection status and ensuring compliance with medication. Future study should exam the impact of HIVST on HIV testing frequency among PrEP users.Trial registration: ChiCTR1800020374 on 27th Dec 2018. http://www.chictr.org.cn/searchproj.aspx