Immunohistochemical Expression Of TNF-α, IL-6, TGF-β And IL-9 In Osteoarthritis: Its Relationship With Cartilage Degeneration

Objective: To investigate the relationship between degeneration of cartilage and the expressions of Tumor Necrosis Factor a (TNF-α) , Transforming Growth Factor p(TGF-p) , Interleukin 6 (IL-6) and Interleukin 9 (IL—9) in osteoarthritis. Methods: The histological changes of cartilages by hematoxyllin-eosin staining and immunohistochemical expression of TNF-α, TGF-p, IL-6 and IL-9 were studied in 20 osteoarthritis cases and 5 normal controls. All data were statistically analyzed by Mann-Whitney U test and correlation analysis.Results: The osteoarthritis cartilage underwent fibroplasias and tearing. The quantity of chondrocyte increased and the clustered and hypertrophic cells came into being. Little immunostaining of TNF-α and IL-6 was observed in normal cartilage, while their expressions increased in degenerated cartilage (P<0.01 ). Expression of TGF-P was the same in normal cartilage, superficial layer of the moderate and end-stage osteoarthritis. However, it significantly increased in deep layer (P<0.01) . As far as the IL-9 in superficial layer was concerned, no difference was found between the normal and moderate osteoarthritis although it was highly expressed in the end-stage osteoarthritis. Meanwhile, the expression of IL-9 in the deep layer was similar in moderate and end-stage osteoarthritis while stronger than the normal controls (P<0.01) . Conclusions: The abnormal expression of TNF-α,IL-6 and TGF-β IL-9 was likely to be the pathogenesis of cartilage degeneration.