Many studies describe a significant association between RA and oxidative stress caused by reactive oxygen species17, 18, 19 and point out that Trx1 levels are augmented in patients suffering from RA20, 21, 22, 23 or other diseases, such as heart,24 lung25 and liver complaints,26 probably counteracting the increased oxidative stress in these diseases. Here, TXN is linked to rheumatoid arthritis.