The mice received a four-collagen–antibodies cocktail intravenously (i.v.) 10 days later (20 days after surgery, day 0). One week later, they received an intraperitoneal (i.p.) injection of LPS to enhance arthritis incidence and severity, and the experiment was terminated on day 14. Control
mice were injected with phosphate-buffered saline (PBS) i.v. and LPS i.p. Male transgenic ERE-luciferase mice were castrated and 11 days later immunized with chicken CII and adjuvant. After 9 days they received one subcutaneous injection of raloxifene, oestradiol or vehicle, and were then terminated 10 h later (day 10 after immunization). Mice were given subcutaneous injections 5 days per week of the raloxifene analogue LY117018 (generous gift from Eli Lilly, Indianapolis, Selleck Small molecule library IN, USA) (60 µg/mouse/day) or 17β-oestradiol-3-benzoate (E2) (Sigma, St Louis, MO, USA) (1·0 µg/mouse/day)
dissolved in Miglyol812 (OmyaPeralta GmbH, Hamburg, Germany). Control mice received Miglyol812 (100 µl/mouse/day). The dosages of Ral and E2 have been shown previously to prevent osteoporosis equally well in mice [19–21]. LY117018 differs from raloxifene at only one site on the molecule, with a pyrrolidine ring on the basic side chain instead of a piperidine ring. This small difference does not affect its biological properties. Thus, INCB024360 mouse Ral and LY117018 can be regarded as replaceable with respect to their biological properties. Experiment 1. Two weeks after ovariectomy DBA/1 mice were immunized with 100 µg of chicken CII (Sigma, St Louis, MO, USA) dissolved in 0·1 m acetic acid and emulsified with an equal volume of incomplete Freund’s adjuvant (Sigma) supplemented with 0·5 mg/ml Mycobacterium tuberculosis (Sigma). A total volume of 100 µl was injected intradermally at the base of the tail. After 21 days, mice received next a booster injection with CII emulsified in incomplete Freund’s adjuvant. Arthritis developed shortly thereafter, and was evaluated continuously for frequency and
severity. Experiment 2. Twenty days after OVX or sham-operation, DBA/1 mice received an intravenous shot of a four-antibody cocktail [monoclonal immunoglobulin (Ig)G antibodies specific for the C1, J1, D3 and U1 epitopes on the collagen type II molecule], according to the protocol of Nandakumar and Holmdahl [10]. Non-arthritic controls received equal volumes of PBS. One week later, all mice received an intraperitoneal injection of 25 µg LPS (Escherichia coli 055 : B5; Difco Laboratories, Detroit, MI, USA). Experiment 3. ERE-luciferase mice were immunized with 100 µg of chicken CII (Sigma) dissolved in 0·1 m acetic acid and emulsified with an equal volume of incomplete Freund’s adjuvant (Sigma) supplemented with 0·5 mg/ml M. tuberculosis (Sigma). A total volume of 100 µl was injected intradermally at the base of the tail.