Laboratory for Bacterial Evolution and Pathogenesis (LBEP)

Bovine Staphylococcus superantigens stimulate the entire T cell repertoire of cattle

New article reveals a key role of S. aureus superantigens in bovine immune evasion

We have just published a new article entitled "Bovine Staphylococcus aureus superantigens stimulate the entire T cell repertoire of cattle" in the journal Infection & Immunity.

This is the article's abstract:

Superantigens (SAgs) represent a diverse family of bacterial toxins that induce Vβ-specific T cell proliferation associated with an array of important diseases in humans and animals, including mastitis of dairy cows. However, an understanding of the diversity and distribution of SAg genes among bovine Staphylococcus aureus and their role in the pathogenesis of mastitis is lacking. Population genomic analysis of 195 bovine S. aureus isolates representing 57 unique sequence types revealed that strains encode 2 to 12 distinct SAgs and that the majority of isolates contain 5 or more SAg genes. A genome-scale analysis of bovine reference strain RF122 revealed a complement of 11 predicted SAg genes, which were all expressed in vitro. Detection of specific antibodies in convalescent cows suggests expression of 7 of 11 SAgs during natural S. aureus infection. We determined the Vβ T cell activation profile for all functional SAgs encoded by RF122 revealing evidence for bovine host-specific activity among recently identified RF122-encoded SAgs SElY and SElZ. Remarkably, we discovered that some strains have evolved the capacity to stimulate the entire T-cell repertoire of cattle through an array of diverse SAgs suggesting a key role in bovine immune evasion.

For more information, you can find the paper here.

Full citation:

Wilson GJ, Tuffs SW, Wee BA, Seo KS, Park N, Connelley T, Guinane CM, Morrison WI, Fitzgerald JR. Bovine Staphylococcus aureus superantigens stimulate the entire T cell repertoire of cattle. Infect Immun. 2018 Sep 10. pii: IAI.00505-18. doi: 10.1128/IAI.00505-18.