Cloning of equine chemokines eotaxin, monocyte chemoattractant protein (MCP)-1, MCP-2 and MCP-4, mRNA expression in tissues and induction by IL-4 in dermal fibroblasts

• Published in: Veterinary immunology and immunopathology Vol. 76; no. 3; pp. 283 - 298
• Main Authors: Benarafa, Charaf, Cunningham, Fiona M, Hamblin, Anne S, Horohov, David W, Collins, Margaret E
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 31.10.2000
• Subjects: Amino Acid Sequence; Animals; Base Sequence; Chemokine; Chemokine CCL11; Chemokines, CC - biosynthesis; Chemokines, CC - genetics; Chemokines, CC - immunology; Cloning, Molecular; DNA, Complementary - chemistry; DNA, Complementary - genetics; Eosinophil; Eosinophils - immunology; Eosinophils - metabolism; Eotaxin; Fibroblasts - immunology; Fibroblasts - metabolism; Horse; Horses - genetics; Horses - immunology; Horses - metabolism; Interleukin-4; Interleukin-4 - biosynthesis; Interleukin-4 - genetics; Interleukin-4 - immunology; Leukocyte Count; Molecular Sequence Data; monocyte chemoattractant protein 1; monocyte chemoattractant protein 2; monocyte chemoattractant protein 4; Monocyte Chemoattractant Proteins - biosynthesis; Monocyte Chemoattractant Proteins - genetics; Monocyte Chemoattractant Proteins - immunology; Reverse Transcriptase Polymerase Chain Reaction - veterinary; RNA, Messenger - biosynthesis; RNA, Messenger - genetics; Sequence Homology, Amino Acid; Skin - cytology; Skin - immunology; Skin - metabolism; Chemokine; Interleukin-4; Eotaxin; Eosinophil; Horse
• ISSN: 0165-2427; 1873-2534
• DOI: 10.1016/S0165-2427(00)00222-1

We report the cloning of four equine CC chemokines, eotaxin, monocyte chemoattractant protein (MCP)-1, MCP-2 and MCP-4, which show high levels of identity with their respective homologous sequences in other species. Using a multiplex RT–PCR, we have studied the constitutive mRNA expression of these four CC chemokines in skin, lung, liver, spleen, jejunum, colon and kidney of normal adult horses and compared this data with the eosinophil counts in the same samples. We demonstrate that eotaxin mRNA is only expressed in jejunum and colon, where there are large numbers of eosinophils suggesting that eotaxin might be recruiting eosinophils in the normal digestive tract of the horse. MCP-1 and MCP-4 are expressed in all tissues whereas MCP-2 is only found in some samples of lung, spleen, liver and kidney. We also report the early induction (2 h) of equine eotaxin and MCP-4, and the up-regulation of MCP-1 by interleukin-4 in dermal fibroblasts, suggesting these chemokines might be involved in equine skin allergic diseases.