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

Objective To determine whether lactoferrin can modify articular inflammation in murine models of autoimmune and septic arthritis. Methods Collagen arthritis was induced in DBA/1 mice and Staphylococcus aureus septic arthritis in Swiss mice. Joints with established inflammation were 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 suppressed local inflammation for up to 3 days, achieving up to 71% of the effect of corticosteroid. Periarticular injection of 125I-lactoferrin confirmed that 25% of lactoferrin was retained in paws after 6 hours. Serum levels of interleukin-6, however, were not significantly reduced, suggesting a predominantly local antiinflammatory effect. Similarly, local, periarticular administration of lactoferrin into S aureus–infected Swiss mice significantly suppressed paw inflammation and did not enhance bacterial survival. Conclusion Lactoferrin may have clinical utility in reducing articular inflammation, particularly in septic arthritis, in which antiinflammatory effects may be achieved without promoting bacterial survival.