Effect of elevated environmental temperature on the antibody response of mice to Trypanosoma cruzi during the acute phase of infection

Abstract

When held at 36°C, Trypanosoma cruzi-infected C3H mice survive an otherwise lethal infection with significantly decreased parasitemia levels and enhanced immune responsiveness. Treatment of T. cruzi-infected mice with the immunosuppressive agent cyclophosphamide indicated that the positive effects of increased environmental temperature were primarily due to enhancement of immunity. A parasite-specific, enzyme-linked immunosorbent assay and immunoblot analysis were used to examine the effect of elevated environmental temperature on the production of anti-T. cruzi antibodies. Both the reactivity and diversity of anti-T. cruzi antibodies were found to be lower in infected mice held at 36°C than in infected mice held at room temperature. However, reactivity and diversity could be enhanced by vaccination with culture forms of the parasite.

Protracted Shedding of Oocysts of Neospora caninum by a Naturally Infected Foxhound

“…The development of humoral immunity during T. cruzi infection in C3HeB/FeJ mice held at 36 C and room temperature (RT) also has been examined using a parasite-specific enzymelinked immunosorbent assay and immunoblot analysis. Although levels of anti-T. cruzi antibodies were initially lower in mice maintained at 36 C, reactivity of parasite-specific antibodies (as well as the number of parasite antigens recognized) continued to increase throughout the course of infection, peaking during the chronic stages of the disease (Dimock et al, 1991(Dimock et al, , 1992. The authors suggest that parasite-specific antibody levels peak too late to play an important role in the acute phase of infection, but it is speculated that antibodies may exert a protective effect later in infection.…”

“…Reports that elevated ambient temperature can positively influence the resistance of the vertebrate host to infection with the protozoan parasite Trypanosoma cruzi have been in the literature for over 50 yr (Kolodny, 1939(Kolodny, , 1940Amrein, 1967;Marinkelle and Rodriguez, 1968). However, this phenomenon has been particularly well documented for C3H mice infected with a Brazil strain of T. cruzi (Anderson and Kuhn, 1989;Dimock et al, 1991;Arif et al, 1999). Maintenance of T. cruziinfected C3H mice at 36 C not only increases longevity and decreases parasitemia, but also results in greatly reduced cardiac and skeletal muscle pathology (Arif et al, 1999).…”

“…Several investigators have suggested that the beneficial effects of elevated temperature during parasitic infection are largely attributable to enhanced humoral, or cell-mediated, immune responses. Immunosuppressive drugs such as cyclophosphamide (Otieno, 1973;Dimock et al, 1991) or whole-body X-irradiation (Otieno, 1973) have been shown to reverse the beneficial effects of elevated temperature. Furthermore, Anderson and Kuhn (1989) demonstrated that maintenance of infected mice at 36 C results in a significant enhancement of the T. cruzi-specific T helper cell response and the direct plaque-forming cell response to sheep red blood cells.…”