Researchers from Karolinska Institutet and Imperial College London have uncovered how sex hormones, like testosterone and oestrogen, influence the immune system, explaining why men and women are affected by diseases differently. In a study involving 23 transgender men undergoing testosterone therapy, they found that increased testosterone and reduced oestrogen altered key immune signaling systems, including antiviral interferon type 1 (IFN-1) and pro-inflammatory signals like tumour necrosis factor alpha (TNF-α). These changes help explain differences in disease risk, such as why males are more prone to severe infections like COVID-19, while females are more affected by autoimmune diseases. The findings, published in Nature, could lead to targeted treatments and highlight the importance of long-term monitoring for trans individuals on hormone therapy.
How might these findings change the way we approach treatments for immune-related diseases in men, women, and transgender individuals?