Low-dose intra-articular autologous conditioned serum in treatment of primary knee osteoarthritis

Background : Interleukin-1 (IL-1) plays an important role in the pathogenesis of osteoarthritis. Hence, agents that inhibit such cytokine have a high therapeutic potential. A method of therapy depends on competitive inhibition of IL-1 at the receptor level-that is, IL-1 receptor antagonist ; such antagonist is called Orthokin, which is a normal product of monocytes and is prepared within autologous conditioned serum (ACS) from the patient’s own blood cells. It is capable of blocking the effects of IL-1, including the induction of matrix metalloproteinases, prostaglandin E2 synthesis, and expression of other cytokines. Objective : The aim of the study was to clinically evaluate the effect of intra-articular injection of low-dose ACS enriched with Orthokin on primary knee osteoarthritis to assess its validity in treatment. Patients and methods : This study included 30 knees with primary osteoarthritis. Baseline clinical evaluation using WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) score was performed. Then ACS enriched with Orthokin (IL-1 receptor antagonist) was prepared. The knee joint was injected with 1 ml ACS weekly for 3 successive weeks. Patients were assessed using WOMAC questionnaire (1 week after each injection for 3 weeks and monthly after the last injection for 3 months). Results : On comparing WOMAC score with baseline data, there was a highly significant improvement in all scores, where P was less than 0.01 during all assessment periods and improvement persisted until the end of follow-up after 3 months in comparison with baseline data. Conclusion : The synthesis and introduction of interleukin-1 receptor antagonists derived from own blood cells established a promising strategy in the treatment of osteoarthritis.