Adjuvant‐induced polyarthritis. synovial cell activation prior to polyarthritis onset

We studied synoviocytes obtained from rats that had been injected with Freund's complete adjuvant 12 days prior to killing. We found that several activation parameters were affected in these synoviocytes, namely, the concanavalin A protein‐binding pattern, the production of superoxide, and the appearance of the p77 polypeptide, which we have previously shown to be associated with the activation caused by the induction of polyarthritis. Our findings suggest that prior to the establishment of the inflammatory process, synoviocytes are in a state of activation, and may be a component of the molecular mechanism during the early stages of disease.