How to cite this article: Vet. Res. (2008) 39:29
DOI: 10.1051/vetres:2008005

CD44 is highly expressed on milk neutrophils in bovine mastitis and plays a role in their adhesion to matrix and mammary epithelium

Erez Gonen^{1, 2}, Shlomo Nedvetzki², David Naor² and Nahum Y. Shpigel<sup>1

1</sup>  The Koret School of Veterinary Medicine, Faculty of Agriculture, POB 12, Rehovot 76100, Israel
²  The Lautenberg Center for General and Tumor Immunology, Faculty of Medicine, POB 12272, Jerusalem 91120, Israel

(Received 6 August 2007; accepted 19 December 2007; published online 15 February 2008)

Abstract - Mastitis, inflammation of the mammary gland, is a common and economically important disease in dairy animals.Mammary pathogenic organisms, such as Escherichia coli, invade the teat canal,milk ducts, and mammary alveolar space, replicate in mammary secretions, and elicit a local inflammatory response characterized by massive recruitment of blood polymorphonuclear neutrophil leukocytes (PMN) into the alveoli and milk ducts. CD44 is a trans-membrane glycoprotein previously shown to play a role in mediation and control of blood PMN recruitment in response to inflammatory signals. Here we show, for the first time, increased expression of CD44 on recruited milk PMN in bovine mastitis and the expression of a CD44 variant, CD44v10, on these PMN. Furthermore, we demonstrate that CD44 mediates specific adhesion of bovine blood PMN to hyaluronic acid and mammary epithelial cells. Our results suggest that in mastitis CD44 plays a role in recruiting blood PMN into the mammary glands, the exact nature of this role needs to be elucidated.

Key words: mastitis / CD44 / neutrophils

Corresponding author: shpigeln@agri.huji.ac.il

© INRA, EDP Sciences 2008