Regulation of chemokine gene expression by contact hypersensitivity and by oral tolerance

In mice with hapten-induced CH, T cells of the CD4+ and CD8+ phenotypes activated the gene for JE, whereas CD8+ T cells alone caused activation of the gene for IP-10. In animals tolerized by feeding either TNCB or OX, hapten-induced expression of IP-10 but not JE mRNA was lost. The down-regulation of IP-10 gene activation was adoptively transferred from tolerized mice to naive mice by CD4+ splenic T cells. These findings reflect the differential roles of individual T-cell subsets in both enhancing and diminishing chemokine gene expression in contact hypersensitivity reactions.