Differences in functional immune responses of high vs. low hardy healthy individuals

An association between the personality trait of hardiness and immune respon ses was explored. Blood samples were collected from 21 healthy individuals under nonstressful conditions, who had either high or low levels of hardine ss. Functional immune assays tested for natural killer (NK) cell activity a nd proliferation responses to Candida albicans (Candida), purified protein derivative from Mycobacterium tuberculosis (PPD), lipopolysaccharide (LPS), concanavalin A (Con A), and Staphylococcus enterotoxin A (Staph A). Differ ences between high and low hardy groups on these immune responses were exam ined using Bonferroni adjusted independent t-tests. Results revealed signif icant differences between the groups for Candida, PPD, Con A, and Staph A. In all instances, the high hardy group had larger mean proliferative respon ses than the low hardy group. Implications of the study as well as avenues for future research are discussed.