Significantly elevated expression of PF4 (platelet factor 4) and eotaxin in the NOA mouse, a model for atopic dermatitis

The NOA (Naruto Research Institute Otsuka Atrichia) mouse, an animal model of allergic or atopic dermatitis, exhibits ulcerative skin lesions associat ed with accumulation of mast cells and eosinophils, a significantly increas ed level of serum IgE, and scratching behavior. To investigate genetic cont ributors to the pathological process of dermatitis in this murine model, we looked for genes that were expressed differently in spleens of NOA mice co mpared with controls, by means of a differential display method. We cloned and characterized one gene that revealed a significantly higher expression in the NOA mouse than in control strains. Its cDNA consisted of 570 nucleot ides, including 315 nucleotides of open reading frame encoding 105 amino ac ids. The deduced amino acid sequence identified this gene as the murine hom ologue of rat and human platelet factor (PF) 4s (89% identity and 64% ident ity in 105 amino acids, respectively). PF4 is a heparin-binding protein tha t is released from alpha-granules of activated platelets and belongs to the family of chemokine molecules that contain a CXC motif. Our results sugges ted that increased expression of PF4 may play an important role in the etio logy of allergic dermatitis.