Cellular immune response in Lyme disease: the response to mitogens, live Borrelia burgdorferi, NK cell function and lymphocyte subsets.

Although some manifestations of Lyme disease may be secondary to the presence of B. burgdorferi, the immune system appears to play a significant role in the clinical manifestations of the disease. The humoral response is well characterized, however the cellular response remains poorly defined. To further define cellular immunity in Lyme disease, the responses of lymphocytes from patients with active Lyme disease were assessed to Con a, PHA, PWM, tetanus toxoid, and whole live B. burgdorferi. In addition, the natural killer cell (NK) function of these patients was assayed. As compared to the controls the lymphocyte response to Con A was reduced and the response to PHA was increased. There was a significant proliferative response to B. burgdorferi in all patients with no response in the controls. The responses to PWM and tetanus toxoid were not different in the two groups. NK cell function in the patients with active disease was reduced as compared to the normal controls and patient's who were not clinically active. We conclude that there is a significant alteration in cellular immunity in active LD consistent with a defect in the induction of suppressor cells leading to a vigorous humoral response.