The COVID19 coronavirus SARS-CoV2 spreading in Wuhan and now worldwide has been shown to use angiotensin-converting enzyme 2 ACE2 as its host cell receptor, like the severe acute respiratory syndrome coronavirus (SARS-CoV). Epidemiology studies found different sex and age groups have different susceptibility to infection, and very skewed severity and mortality of the virus infection, with male, old age, and comorbidity being the most inflicted. Here by analyzing GTEx and other public data in 30 tissues across thousands of individuals, we found significantly higher expression in Asian females compared to males and other ethnic groups, an age dependent ACE2 expression decrease and a highly significant decrease in type II diabetic patients. Consistently, the most significant expression quantitative loci (eQTLs) contributing to high ACE2 expression are close to 100% in East Asians, >30% higher than other ethnic groups. Together with the shockingly common enrichment of viral infection pathways among ACE2 anti-expressed genes, binding of virus infection-related transcription factors at ACE2 regulatory regions, the repression of ACE2 expression by inflammatory cytokines and by type 2 diabetes, and the induction by estrogen and androgen (both decrease with age) established a negative correlation between ACE2 expression and CovID19 fatality at both population and molecular levels. Our results will be instrumental when designing potential prevention and treatment strategies for ACE2 binding coronaviruses in general.

Trichinella spiralis (T. spiralis), a nematode parasite, is the major cause of Trichinellosis, a zoonotic disease. A key role of MAPR in the reproductive system is to maintain pregnancy. Previous studies found antihormone (P4 and RU486) drug design and vaccine therapy of recombinant protein (rTs-MAPRC2) to control T. spiralis infection. The current study investigates the inhibitory effects of different ratios of antibody against Ts-MAPRC2 on the development of muscle larvae (ML) and newborn larvae (NBL). First, we performed indirect immunofluorescence assays (IIFA) and examined the effects of rTs-MAPRC2-Ab on ML and NBL in vitro as well as in vivo. After-ward, siRNA-Ts-MAPRC2 was transfected into T. spiralis muscle larvae. Following that, Ts-MAPRC2 protein was detected by Western Blotting and mRNA levels were determined by qPCR. Also, we assessed whether siRNA-treated NBLs were infective by analyzing muscle larvae burden (MLs). Our Result showed rTs-MAPRC2-Ab greatly inhibited the activity of the Ts-MAPRC2 gene in ML and NBL of T. spiralis. rTs-MAPRC2-Ab reduced larval infectivity and survival in the host in a dose-dependent manner (1:50, 1:200, 1:800 dilutions). Further, siR-NA-Ts-MAPRC2 effectively silenced the Ts-MAPRC2 gene in muscle larvae (ML) by in vitro, as well as in new-born larvae (NBL) of T. spiralis by in vivo. In addition, siRNA-Ts-MAPRC2 (siR-NA180, siRNA419, siRNA559) reduced host larval survival and infectivity significantly. The effect of siRNA on larval development, survival, and infectivity was significantly reduced when the Ts-MAPRC2 gene was knocked down. This study, therefore, suggests that Ts-MAPRC2 might be a novel molecular target that might be useful in the development of vaccines against T. spiralis infection.