Sex Differences in the Associations Among Sickness Behavior, Immune Status, and Immune Function in an Adolescent Murine Model

Open Access
Author:
Buckley, Patrick James
Area of Honors:
Biobehavioral Health
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Laura Klein, Thesis Supervisor
  • David John Vandenbergh, Honors Advisor
  • Stephen Wade Schaeffer, Faculty Reader
Keywords:
  • sickness behavior
  • immune
  • adolescent
  • mouse
  • sex
Abstract:
Animals exhibit familiar behavioral changes in response to infection including anorexia, adipsia, hypersomnia, and reduced social interaction. The coordinated, non-specific behavioral changes associated with infection are collectively known as “sickness behavior”. Experimental evidence suggests that sickness behavior is not a passive consequence of infection but rather an adaptive strategy that complements physiological and immunological responses to infection. Although the immune system changes over the course of the lifespan, there is currently no research investigating sickness behavior during adolescence, a critical period of development. The purpose of this thesis was to investigate the association between sickness behavior, immune status, and immune function in periadolescent (PN 28-42) C57BL/6J mice infected with herpes simplex virus (HSV)-1. Food consumption, water intake, and body weight were measured for male (n=19) and female (n=20) C57BL/6J mice over eleven days. On day 6, all mice were infected with HSV-1 in both rear foot pads. On day 11, mice were sacrificed and popliteal lymph nodes were removed to observe immune status (lymphocyte production of interferon (IFN)-γ) and function (HSV-1 specific T-lymphocyte lysis) in response to HSV-1 infection It was hypothesized that there would be positive correlations between measures of sickness behavior and measures of immune status and function. Largely, these hypotheses were not supported by the analyses. There was a significant correlation between decrease in liquid consumption and immune function in female mice. A discussion of these results indicates limitations of this analysis and possible future directions for this line of research.