Recently we discovered and purified a novel beta-chemokine with eosinophil specific chemotactic activity from supernatants to long-term TNF-alpha stimulated dermal fibroblasts. Using degenerated specific oligonucleotides based on partial amino acid sequence data and a PCR protocol, we obtained different clones sharing high sequence homology with this novel chemokine and with human eotaxin cDNA. Semi-quantitative RT-PCR experiments using eotaxin-specific primers indicate low constitutive eotaxin mRNA expression in human dermal fibroblasts which is upregulated by IL-1 alpha and TNF-alpha within 6 hrs and modulated by IFN-gamma. While IL-1 alpha-induced eotaxin mRNA accumulation is transient, long-term stimulation with TNF-alpha resulted in a further increase of eotaxin mRNA.