Lymphocyte polyclonal activation: A pitfall for vaccine design against infectious agents

In this article, Bernardo Reina-San-Martin, Alain Cosson and Paola Minoprio summarize the marked alternations ill the immune system functions after in fection that might account for rite poor success of effective parasite vacc ine devel- opment. Many of the studies on oligoclonal B- and T-cell respons es to parasite antigens aiming at vaccination strategies would seem to igno re more general, and perhaps fundamental, aspects of parasite-immune system interactions. In essen ce, because of its consequences on immunopathology and parasite escape, the authors ascribe a central importance in the pathog enesis of parasitic diseases to the 'nonspecific' polyclonal lymphocyte act ivation that occurs during infection. Hence, novel targets and strategies f or immune intervention should be considered.