T lymphocyte subpopulations in Tripanosoma Cruzi infected individuals with different electrocardiographic alterations

pp 78-81

Abstract

It is already known that theophylline incubation of peripheral T lymphocytes (T cells) allows their separation into two subsets; one that retains the ability to form E rosettes with sheep red blood cells and exerts helper activity on B cells (theophylline resistant T cells -ThR T cells-); the other one that loses this characteristic and develops suppressor activity on the same system (theophylline sensitive cells). Circulating levels of total T cells and ThR T cells -by means of rosette formation with and without theophylline incubation respectively-, were assessed in the present work, in two groups of Trypanosoma cruzi (Tc) infected individuals. Group 1: patients without electrocardiographic (ECG) alterations. Group 2; patients with moderated EeG alterations. A group of normal individuals was also included as control. A decrease in circulating levels of total T cells and ThR T cells in Tc- infected individuals with moderate EeG altera- tions (compatible with chronic chagasic myocar- diopathy) was seen in relation to controls. However, the proportion of ThR T cells within total T cells was not modified. It is postulated that such decrease of immunocompetent cell populations might reflect an immunorregulatory mechanism, intended to avoid excessive immunological response, eventually harmful to host tissues.