Psychobehavioral and immunological characteristics of HTLV-1 carriers and non-carriers with persistently low natural killer cell activity

Abstract

Objective: To clarify the differences in immunological and psychobehavioral characteristics of HTLV-1 carriers and non-carriers with persistently low natural killer (NK) cell activity. Methods: The individuals with persistently low NK cell activity were divided into HTLV-1 carriers and non-carriers. NK cell activity, lymphocytic proliferation, lymphocyte subsets (CD4+, CDS+, CD16+, CD20+, CD56+), and psychobehavioral responses were examined. Patients: Of 296 outpatients with physical complaints, 30 patients with persistently low NK cell activity (10 HTLV-1 carriers and 20 HTLV-1 non-carriers) and 20 healthy controls negative for HTLV-1 antibody and with normal NK cell activity were randomly selected. Results: In HTLV-1 carriers with persistently low NK cell activity, no significant differences were observed in NK cell subsets (CD16+ and CD56+) and psychobehavioral responses compared with the healthy controls. In HTLV-1 non-carriers, NK cell subsets were significantly low, and depression, anxiety and fatigue were significantly greater than in healthy controls. Conclusions: These findings suggest that persistently low NK cell activity in HTLV-1 carriers might be reduced due to the HTLV-1 infection. On the other hand, the reduction in the NK cell activity in HTLV-1 non-carriers appears to be related to depression, anxiety, and fatigue.