Sex Differences in Lung Immunity

ABSTRACT Biological sex has a significant impact on how the immune system develops and responds to foreign and self‐antigens. Sex differences exist in innate and adaptive immune cells, both at homeostasis and in the context of infection and inflammatory diseases such as asthma, cancer, and autoimmune disorders. Women generate stronger immune responses and are more susceptible to developing autoimmune conditions, while males are more prone to acute viral infections and developing certain cancers. Some immunological differences persist throughout life, while others emerge only after puberty and before reproductive senescence. Additionally, environmental exposures can affect the influence of biological sex in regulating immune function. This is particularly pertinent at mucosal surfaces such as the lungs, where lung immune defenses are constantly exposed to foreign material during respiration. Consequently, environmental factors together with genetics, age and sex hormones play a vital role in governing lung tissue immune responses between the sexes. In this context, we highlight studies that support the need for considering sex as an important biological variable in lung immunological research. This knowledge will provide a benchmark for understanding sex‐driven immunological mechanisms that underpin disease development and may inform new avenues targeted for generating sex‐specific therapies in lung disease.