Molecular cloning of equine interleukin-1α and -β cDNAs

Equine interleukin-1α (IL-1α) and IL-1β were molecularly cloned to establish a basis for research on inflammatory and immune responses in the horse. Equine peripheral blood mononuclear cells (PBMC) were stimulated with lipopolysaccharide (LPS), and cDNA clones of equine IL-1α and IL-1β covering the whole coding sequences were isolated from them. These equine IL-1α and IL-1β clones contained open reading frames encoding 271 and 269 amino acids, respectively. The deduced amino acid sequence of equine IL-1α showed 71.6% and 60.2% similarity with that of human and murine IL-1α, respectively. Similarly, the amino acid sequence of equine IL-1β showed 66.7% and 61.8% similarity with that of human and murine IL-1β, respectively. In both equine IL-1α and IL-1β, amino acids at miristoylation sites were well conserved. Dot blot analysis indicated that the expression of IL-1β was predominant to that of IL-1α in equine PBMC stimulated with LPS or phorbol myristate acetate.