CD4 and rheumatoid arthritis: In RA, CD4 cell count decreased by 37% at three months from a mean of 1.25 × 109/l at baseline (Mélet et al., 2013), remained unchanged at four months from a mean of 0.93 × 109/l at baseline (Thurlings et al., 2008) and increased by 14% from a mean of 0.63 × 109/l at baseline during the first three months (Feuchtenberger et al., 2008).