Davis JM, Crowson CS, Knutson KL, et al. - In this study performed on 155 adult patients with rheumatoid arthritis, researchers examined the links between immunostimulated cytokine generation and disease characteristics. For this purpose, they obtained peripheral blood lymphocytes from the participants before and after a 5-year interval. They activated lymphocytes in vitro with T-cell stimulants, cytosine-phosphate-guanine (CpG) oligonucleotide, and medium alone (negative control). Using immunoassays, they assessed the expression of 17 cytokines. Findings revealed the highest numbers of correlations between cytokine concentrations and rheumatoid factor (RF) positivity and between cytokine levels and disease duration. Results also showed a negative association of scores for cytokines driven by CpG and medium alone, with RF positivity and disease duration at baseline, as well as positive link with both at 5 years. Experts suggested increased activation of B cells and monocytes, without needs for T-cell functions, in relation to RF expression sustained over time.