Objective: To evaluate in vitro migration of mononuclear cells towards synovial fluid (SF) and plasma in relation to RANTES synovial fluid levels and clinical disease activity.
Methods: 31 RA patients with synovitis in one knee were included. Modified Boyden chamber technique was used to determine a migratory index defined as: 'In vitro migrating cells towards SF' divided by 'In vitro migrating cells towards plasma'. RANTES was quantified by ELISA. Disease activity was assessed by the swollen joint count, the Ritchie articular index (RAI), global assessment, pain on VAS, HAQ, ESR and CRP.
Results: A positive significant correlation was found between the migratory index and the RANTES levels in SF (r=0.48, p=0.006), the RAI (r=0.56, p=0.0001) and pain on VAS (r=0.43, p=0.04). The in vitro migration could be inhibited in 3 of 4 SF samples by neutralising antibodies towards RANTES (12-18%).
Conclusion: The migratory index correlate to SF levels of RANTES and parameters for joint pain.