MMP9 and infection: Up-regulation of gene expression of the IL-12 gene family members p19 and p40c, in combination with up-regulation of gene expression of chemokines (CXCb and CXCL8_L2) and of the matrix metalloproteinase MMP-9, suggested infections with T. carassii could be associated with a Th17-like immune response typically associated with neutrophilia.