Recently, two studies using Hsp65-producing L. lactis demonstrated that pre-treatment with Hsp65 prevented the development of colitis (17) and arthritis (66) in mice by inducing CD4+Foxp3+ and CD4+LAP+ Treg cells in a TLR2-dependent manner; in addition, reduced inflammatory cytokine production in the colon (17) and draining lymph nodes (66) were seen. This evidence concerns the gene CD4 and arthritic joint disease.