Abstract

Schistosoma mansoniasis is a disease of grave concern due to its high morbidity and mortality in parts of the world. This study aimed at providing insight into the pathogenesis of S. mansoniasis as an aid in the development of effective control methods. Iron, zinc and copper concentrations were spectrophotometrically measured in sequential serum specimens obtained from baboons throughout the course of acute S. mansoni infection, following curative treatment with praziquantel and following post-treatment challenge with a second cercarial infection. The initial infection resulted in a two-fold increase in copper concentrations by Day 102 post-infection. Iron concentrations fell to almost half of pre-infection concentrations by Day 123 post-infection, while those of zinc fell to a third of pre-infection concentrations by Day 81 post-infection.  These changes were seen to recover several weeks following treatment, though pre-infection concentrations were never achieved. Haptoglobin, a sensitive biomarker in the acute phase response of S. mansoni, was also measured at all sampling points. Haptoglobin changes were in concordance with those of the cations. The findings demonstrate that iron, zinc and copper are reactants in the acute phase response of S. mansoni in the nonhuman primate model, Papio anubis. Furthermore, these reactants are modulated in challenge infections and may be important in the immunopathology of the disease.

Key words: Acute phase response, Schistosomiasis mansoni, serum iron, serum zinc, serum copper.