Understanding mechanisms of sex disparities in infectious diseases

The mortality rate for COVID-19 pandemic has been two-fold higher in men than women. Similar observation extends to susceptibility and outcome of most other infectious diseases. For instance, after initial Hepatitis C Virus infection women are 2-3 times more likely to spontaneously clear the virus without any interventions and in HIV infection females are 5 times more likely to achieve elite control (complete suppression virus without therapy) than men. However, a consequence of the more vigorous immune response observed in females is more immunopathology and auto-immune diseases (such as lupus) in women than men. For the same reasons, females make stronger immune responses to vaccines but suffer more adverse events. Despite large evidence for sex differences in autoimmune diseases and susceptibility and outcome of infectious diseases, data addressing the biological mechanism are remarkably scarce.

In this project you will use computational and experimental methods to probe differences in immune system that lead to sex differences in infectious diseases. We will investigate this question across many infections including HCV, HBV, HIV and COVID-19. You will start with analysing the available RNA-seq and genomic data from our cohorts and other public databases to understand the role of heterogeneity in X chromosome inactivation in female immune cells and the transcriptional consequence and its contribution to better outcome in infectious diseases. In the next stage you will stimulate male and female immune cells with different immunogens and perform single cell RNA-sequencing to evaluate differential responses across distinct cell types and their association with sex. The project will also use samples and data from vaccine clinical trials. The baseline samples will be compared to the post-vaccination samples and differences in immune systems between sexes will be investigated.