Gene expression of estrogen receptors in PBMC from patients with Puumala virus infection.

The influence of estrogen signaling on infectious diseases is not fully known. Males seem to be more susceptible to infections than females. This has also been noted for the Scandinavian form of hemorrhagic fever with renal syndrome caused by Puumala hantavirus (PUUV). To investigate the differences in estrogen receptors in relation to sex and clinical severity, 20 patients (10 males, 10 females) with confirmed PUUV infection were studied. Real-time polymerase chain reaction was performed for analyzing mRNA expression of estrogen receptor-α (ERα), ERβ, and ERβ2 (ERβ cx) in peripheral blood mononuclear cells from patients and healthy age- and sex-matched blood donors. Blood chemistry and peripheral blood mononuclear cells sampling were performed during the acute and convalescent phases. None or very small amounts of ERβ were detected, and ERα and ERβ2 mRNA were elevated in the patient group. The samples from the males were correlated with ERβ2; the female samples, with ERα. Furthermore, the female and male samples are partly separated using multivariate statistic analysis (principal component analysis), supporting findings that clinical symptoms differ depending on sex.