Elevated environmental temperature enhances immunity in experimental Chagas' disease.

Area of Science:

• Immunology
• Parasitology
• Environmental Medicine

Background:

• C3H mice are highly susceptible to Trypanosoma cruzi, often succumbing during acute infection with significant immunosuppression.
• Previous studies suggest elevated environmental temperatures may increase host resistance to T. cruzi.

Purpose of the Study:

• To investigate if increased environmental temperature (36°C) enhances host resistance to T. cruzi infection in C3H mice.
• To determine if temperature-induced resistance is mediated by alterations in the host immune response, specifically antibody production and T-helper cell activity.

Main Methods:

• T. cruzi-infected and non-infected C3H mice were maintained at either 36°C or room temperature (20-24°C).
• Mice were immunized with sheep erythrocytes (SRBC) or trinitrophenyl (TNP) conjugates of T. cruzi.
• Splenic direct plaque-forming cell (DPFC) responses to SRBC and TNP-conjugated SRBC were measured to assess antibody production and T-helper cell function.

Main Results:

• Mice infected with T. cruzi and maintained at 36°C exhibited significantly higher DPFC responses to SRBC compared to infected mice at room temperature.
• The antibody response in temperature-acclimated infected mice was comparable to, or slightly higher than, non-infected controls.
• Elevated temperature significantly enhanced parasite-specific T-helper cell responses, indicated by increased anti-TNP DPFC production.

Conclusions:

• Maintaining T. cruzi-infected mice at an elevated environmental temperature of 36°C significantly enhances their resistance to the parasite.
• Increased environmental temperature positively modulates the host immune system, improving both antibody production and T-helper cell responses against T. cruzi.
• Environmental temperature is a critical factor influencing host-parasite interactions and immune outcomes in T. cruzi infections.