Rodent Preclinical Models for Developing Novel Antiarthritic Molecules: Comparative Biology and Preferred Methods for Evaluating Efficacy

Figure 3

The severity of immune-mediated joint disease in rats varies with the model and the choice of reagents. Adjuvant-induced arthritis induced in young adult, male Lewis rats using either lipodal amine (AIA-LA) or Mycobacterium tuberculosis (AIA-Myc) produces extreme swelling and reddening of the tibiotarsal region (hock (or “ankle”)) (upper image) relative to the changes that develop in young adult, female Lewis rats with collagen-induced arthritis (CIA). The degree of hock expansion associated with CIA induction using incomplete Freund's adjuvant (IFA) from Sigma Chemical Co. (St. Louis, MO) (middle image) is greater than that associated with IFA provided by Difco Laboratories (Detroit, MI) (lower image). Intra-articular inoculation of streptococcal cell wall (SCW) polymers results in modest hind paw swelling (not shown).