To delineate the function of TNFR1 in hepatic and splenic cells during arthritis, CIA-negative mice (collagen type II immunized mice without macroscopic signs of arthritis) were injected intravenously with HpTNFR1 or HpNS at day 1 after booster injection (day 22). This evidence concerns the gene TNFRSF1A and arthritic joint disease.