Sex-Specific TMPRSS2 Response and Reduced Peripheral RNA Concentration Following AstraZeneca COVID-19 Vaccination in Nigeria.

A study examined molecular changes in blood samples from Nigerian adults at least 6 months after ChAdOx1 nCoV-19 (AstraZeneca) vaccination. The research included 51 vaccinated participants and 51 unvaccinated matched controls. Vaccinated participants had 37 percent lower total RNA concentration in blood (4.02 ng/uL) compared to unvaccinated individuals (6.38 ng/uL). Expression of ACE2 and TMPRSS2 genes did not differ overall between groups. However, a sex-specific difference was found: vaccinated females had higher TMPRSS2 expression than vaccinated males. Coagulation parameters remained unchanged. The results indicate that vaccination does not lead to sustained elevation of ACE2 and TMPRSS2 and highlight the need for further research on sex-specific vaccine effects in African populations.