Immunopathology of schistosomiasis mansoni in mice and men

Padraic Fallon recently presented an excellent summary of cytokine responses and immunopathology in infected mice and humans1. We wish to take issue with several points, including Fallon’s implication that morbidity and death in immunodeficient mice caused by type 1 cytokine responses is relevant to human schistosomiasis. In this model, hepatocellular toxicity1 and 2 is apparently caused by Schistosoma mansoni egg antigens that are neutralized in immunologically intact mice 2 and 3. Fallon et al. recently presented a detailed description of this response2. In considering the varied causes of morbidity and mortality in humans and mice (Table 1) this toxicity, termed ‘cytokine shock’ in the table, has no apparent counterpart in infected humans.