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Increasing the rate of incidence in the Collagen-induced Arthritis model

Highly purified collagen type II is important for the induction of arthritis. The rate of incidence is a sore topic among many that are running the collagen induced arthritis model given disease incidence as low as 50% is not uncommon.  The purity of the collagen, adjuvant quality, emulsion preparation, animal strain, animal diet, environment and stress are all factors that can affect the rate of incidence. Here are some tips for increasing the rate of incidence in the collagen-induced arthritis model.

bovine collagen type II for induction of the collagen-induced arthritis model

Collagen Type II for inducing arthritis

Use only a highly purified source of collagen (>99%). Ensure that the collagen has not denatured. Keep collagen cold and stored appropriately. Collagen should be a clear solution. If cloudy, the collagen may have cross-linked and precipitate, or it has been contaminated. The concentration of the collagen used will also affect the disease severity. A common concentration is 2 mg/mL and can go up to 4 mg/mL. If you prefer to use 2 mg/mL, we have soluble collagen type II ready to use. For those who have protocols using higher concentrations of collagen type II, use our lyophilized collagen.

 

Animal Health, Age, Strain

Disease susceptibility is strongly linked to the class II molecules of the MHC. Collagen-induced arthritis susceptible mice such as DBA/1, B10.Q and B10.III are the most commonly used strains for the collagen-induced arthritis model. Mice should be young (approx. 8 weeks) and healthy, and male mice are often preferred. The estrogen in female mice may effect the severity/incidence of disease. If other strains such as the C57Bl/6 mouse are preferred, CII from chicken would be recommended over bovine sources. The environment in which the animals are housed can have a large affect upon the rate of incidence. Intestinal bacteria flora, viral and bacterial infections will affect the immune response to collagen and the development of arthritis. Animals should be fed a high fat content diet.

 

Adjuvant and emulsion preparation:
Use high quality CFA at a concentration up to 4 mg/mL. The emulsion should be prepared at cooled temperatures and should be made thick to give the best rate of incidence. The preparation of the CII and the CFA emulsion is a critical step. Insufficient mixing and temperature are common errors at this step. Increase the speed of the homogenixzer (or other mixing apparatus) and keep the reagents and mixing vessel on ice during the emulsification step.  

 

MD Bioproducts contains optimized reagents for induction of the preclinical collagen-induced arthritis model. We perform contract research services in house regularly and can't afford to compromise on the quality of reagents when working with pharmaceutical test compounds. If you have questions establishing the collagen-induced arthritis model in your lab, be sure to contact us for guidance. Our expert in vivo scientists are happy to help.