Immune depression in Trypanosoma brucei brucei infected mice. Sequential histological and immunological findings.

Pathological findings in various organs and tissues, T and B lymphocyte inability to proliferate towards several mitogens, and the appearance of serum interferon at progressive stages after intraperitoneal infection of BALB/c mice with Trypanosoma brucei brucei are reported. Heavy parasitaemia is evident throughout infection and complete hyporesponsiveness is already present on day 3. A sharp interferon production peak appears after 48 hours. The anatomopathological picture makes it clear that infection is substantially restricted to the blood. Secondary involvement of liver, lung and kidney takes the form of perivascular cuffs. These appear at relatively early stages. By contrast, spleen and lymph nodes appear to be greatly altered.