The effects of local administration of lactoferrin on inflammation in murine autoimmune and infectious arthritis

Objective. To determine whether lactoferrin can modify articular inflammati on in murine models of autoimmune and septic arthritis. Methods. Collagen arthritis was induced in DBA/1 mice and Staphylococcus au reus septic arthritis in Swiss mice. Joints with established inflammation w ere injected periarticularly with 0.5 mg or 1 mg of human lactoferrin, and arthritis was monitored for 3 days. Results. DBA/1 mice injected with lactoferrin showed significantly suppress ed local inflammation for up to 3 days, achieving up to 71% of the effect o f corticosteroid, Periarticular injection of I-125-lactoferrin confirmed th at 25% of lactoferrin was retained in paws after 6 hours. Serum levels of i nterleukin-6, however, were not significantly reduced, suggesting a predomi nantly local antiinflammatory effect. Similarly, local, periarticular admin istration of lactoferrin into S aureus-infected Swiss mice significantly su ppressed paw inflammation and did not enhance bacterial survival. Conclusion. Lactoferrin may have clinical utility in reducing articular inf lammation, particularly in septic arthritis, in which antiinflammatory effe cts may be achieved without promoting bacterial survival.