Sex-Specific Regulation of Peripheral and Central Immune Responses
- Sabra L. KleinSabra L. KleinDepartment of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University
- and Jaclyn M. SchwarzJaclyn M. SchwarzDepartment of Psychological and Brain Sciences, University of Delaware
Sex is a biological variable that affects immune responses to both self and foreign antigens (e.g., microbial infections) in the central nervous system (CNS) as well as in peripheral organs. The sex of an individual is defined by the differential determination of the sex chromosomes, the organization of the reproductive organs, and the subsequent sex steroid hormone levels in males and females. Sex is distinct from gender, which includes self-identification as being a male or female as well as behaviors and activities that are determined by society or culture in humans. Male and female differences in immunological responses may be influenced by both sex and gender, with sex contributing to the physiological and anatomical differences that influence exposure, recognition, clearance, and even transmission of microbes in males and females. By contrast, gender may reflect behaviors that influence exposure to microbes, access to health care, or health-seeking behaviors that indirectly affect the course of infection in males and females. Though both sex and gender influence the immune response, the focus of this article is the biological factors that influence immunological differences between the sexes in both the CNS and peripheral tissues to alter the course of diseases across the life span.