The effect of infection on T lymphocyte subpopulations: a preliminary report.

The effect of cytomegalovirus (CMV) infection on T-lymphocyte subpopulations (employing the monoclonal antibody OKT4 to delineate helper cells and OKT8 for suppressor-cytotoxic cells) was studied in 10 normal individuals with CMV mononucleosis and four renal transplant patients with symptomatic primary CMV disease. In both clinical settings, acute CMV infection is associated with a reversal of the normal helper/suppressor-cytotoxic T cell ratio, with both a relative and absolute decrease in T helper cells and an increase in T suppressor-cytotoxic cells observed. With clinical recovery, there is a return of these cell populations toward normal ranges. In two patients, one with chronic CMV infection and one with chronic Epstein-Barr virus infection, the helper/suppressor-cytotoxic cell ratio was found to be reduced four years after the onset of infection. Five patients with febrile illnesses were also studied: two with viral infection and one with a self-limited febrile illness had decreased helper/suppressor-cytotoxic cell ratios, and two with bacterial infection had increased ratios. Thus, delineation of T lymphocyte subpopulations may be of value not only in evaluating the immunologic effects of a particular infectious agent, but also in the clinical evaluation of the febrile patient.