Lactobacillus casei cell wall-induced arthritis in rats: Cell wall fragment distribution and persistence in chronic arthritis-susceptible LEW/N and -resistant F344/N rats

We recently reported that chronic polyarthritis could be induced in LEW/N rats by the injection of group B Lactobacillus casei cell walls in aqueous suspension. To confirm and extend this model we evaluated the pattern of disease in female LEW/N and F344/N rats injected with group B L casei cell wall fragments. Female LEW/N rats developed both acute and chronic polyarthritis following injection, but F344/N rats developed only acute arthritis. To evaluate the role of cell wall deposition and persistence in the pathogenesis of acute and chronic arthritis in these 2 inbred rat strains, group B L casei cell walls internally labeled with ¹⁴C L-lysine were prepared and the distribution and persistence of the cell wall fragments measured 1, 3, 20, and 66 days following a single intraperitoneal injection. Labeled group B L casei cell wall fragments were widely distributed and persistent throughout the limbs and tissues of both chronic arthritis-susceptible LEW/N and chronic arthritis-resistant F344/N female rats. The absence of a difference in cell wall distribution between arthritis-susceptible and -resistant inbred rat strains supports the previous hypothesis that inbred LEW/N and F344/N rats differ in their ability to respond to, or neutralize, arthritogenic gram-positive cell wall fragments.