A study has shown that natural killer cell receptors CD94 and NKG2A are expressed at higher levels in patients in remission from rheumatoid arthritis (RA) following TNF blockade than in those with active RA. Low levels of these receptors were associated with disease flare following therapy withdrawal. This differential expression could provide predictive markers for flare and might allow for cost-reducing therapy holidays in patients in remission without risking disease flare.