The antibacterial psoriasin is induced by infection in the bovine udder

Petra Regenhard , Wolfram Petzl , Holm Zerbe , Helga Sauerwein

Human psoriasin (S100A7) has been described as a member of the family of S100 calcium-binding proteins and is over-expressed in patients suffering from psoriasis. The bovine homolog was first identified as a cow-derived respiratory allergen. Human psoriasin as well as its bovine homolog exhibit antibacterial activity especially against . During mastitis, the host defence status is a cardinal factor influencing systemic disease severity, and -mastitis is a common problem in dairy cattle We therefore examined by immunoblotting and immunhistochemistry whether and in which location the bovine protein is expressed in the mammary gland and whether this expression is inducible by -infection. Additionally, milk samples from the cows were investigated. To obtain an antiserum, rabbits were immunised with recombinant bovine psoriasin. Six German Holstein cows in their first lactation were used; 4 of them were intramammarily infected with an strain isolated from udder secretions of cows with clinical mastitis, 2 cows served as healthy control animals. After 24h, cows were slaughtered and samples were collected from 3 different locations of the quarters. Psoriasin expression was limited to the teat cistern of the - infected cows, but was absent in the teat cistern of the non-infected cows and in the parenchyma of both groups, whereas the expression on udder skin was demonstrated in both infected and non-infected cows. Psoriasin thus appears to be a part of the local host defence mechanisms in the udder and seems to be inducible by infection with .

Mots clés: mastitis; dairy cows; antimicrobial peptides

Petra Regenhard, Wolfram Petzl, Holm Zerbe, Helga Sauerwein. The antibacterial psoriasin is induced by infection in the bovine udder. Veterinary Microbiology, 2009, 143 (2-4), pp.293. ⟨10.1016/j.vetmic.2009.11.035⟩. ⟨hal-00509710⟩