The observed decreased production of RANTES and increased levels of MCP-1, a chemokine associated with the Th2-type responses, in our SC subjects points to a blunted production of related Th1 molecules and to an under-activation of the Th2 system in schizophrenia, confirming an alteration of the Th1/Th2 balance as hypothesized by other authors [12,38]. This evidence concerns the gene CCL5 and schizophrenia.