Importantly, that incidence was reduced by 50% when TGFβ was blocked during acute infection in O mice (Fig 5C), whereas, neutralization of TGFβ in A mice made the late joint pathology worse (Fig 5C), suggesting that in a properly controlled response in A mice, TGFβ plays a protective role in joint infiltration and pathology. This evidence concerns the gene TGFB1 and infection.