Sex differences in innate anti-viral immune responses to respiratory viruses and in their clinical outcomes in a birth cohort study.

The mechanisms explaining excess morbidity and mortality in respiratory infections among males are poorly understood. Innate immune responses are critical in protection against respiratory virus infections. We hypothesised that innate immune responses to respiratory viruses may be deficient in males. We stimulated peripheral blood mononuclear cells from 345 participants at age 16 years in a population-based birth cohort with three live respiratory viruses (rhinoviruses A16 and A1, and respiratory syncytial virus) and two viral mimics (R848 and CpG-A, to mimic responses to SARS-CoV-2) and investigated sex differences in interferon (IFN) responses. IFN-α responses to all viruses and stimuli were 1.34-2.06-fold lower in males than females (P = 0.018 - < 0.001). IFN-ß, IFN-γ and IFN-induced chemokines were also deficient in males across all stimuli/viruses. Healthcare records revealed 12.1% of males and 6.6% of females were hospitalized with respiratory infections in infancy (P = 0.017). In conclusion, impaired innate anti-viral immunity in males likely results in high male morbidity and mortality from respiratory virus infections.

Assessment of immunodeficiency scoring index performance in enterovirus/rhinovirus respiratory infection after allogeneic hematopoietic stem cell transplantation.

BACKGROUND: Enterovirus/rhinoviruses (EvRh) are the most common cause of respiratory virus infections in recipients of allogeneic stem cell transplantation (allo-HSCT). OBJECTIVE: We sought to analyze the value of the immunodeficiency scoring index (ISI) in predicting lower respiratory tract disease (LRTD) progression and mortality in a prospective cohort of consecutive adult (>16 years) allo-HSCT recipients with EvRh infection from December 1 2013 to December 1 2019 at two Spanish transplant centers. RESULTS: We included 234 allo-HSCT recipients with 383 EvRh episodes. Out of 383 EvRh episodes, 98 (25%) had LRTD. Multivariate logistic regression analysis identified three independent factors associated with LRTD progression: Ig G < 400 mg/dL, community-acquired respiratory virus (CARV) co-infection and high-risk ISI. Inclusion of Ig G levels and CARV co-infection in the ISI improved its performance by significantly increasing the area under the receiver operator characteristic curve (AUROC) from 0.643 to 0.734 (P = .03). Likewise, the two conditions identified by multivariate analyses as associated with higher probability of mortality were high-risk ISI and EvRh infection within 6 months after transplant. CONCLUSIONS: Our findings confirm the value of high-risk ISI in predicting both probability of EvRh LRTD and 3-month overall mortality. We also demonstrate that the original ISI could be adapted to other CARV types by including additional variables to improve its performance.