Application of interleukin-1 genes and proteins to monitor the status of chronic periodontitis.

It has been widely reported that periodontitis may lead to bone tissue and teeth loss and result in failure of prosthodontics or implants. Interleukin-1 (IL-1) is a potent proinflammatory cytokine that plays an essential role during the pathogenesis of periodontitis. However, the gene polymorphisms of IL-1α, IL-1β and IL-1RN and the relationship between these protein expressions in healthy people and patients with chronic periodontitis (CP) in China have not been fully elucidated. We investigated the gene polymorphisms and protein expression of IL-1α, IL-1β and IL-1RN in healthy subjects and CP patients, and our data suggest that these gene polymorphisms are associated with CP. The frequency of the C/C genotype of IL-1α was 55% in CP patients, while in the control group it was 20% (p<0.0001). The C/C genotype of IL-1β was also higher in CP patients (51%) than in controls (21%) (p<0.0001). For the 2/2 genotype of IL-1RN, CP patients showed a 30% frequency, while in controls this was 15% (p<0.0001). Protein levels evaluated by enzyme-linked immunosorbent assay demonstrated a significant difference in secretion between patients and controls for IL-1α and IL-1β. These results indicate that genotype and protein production of IL-1α, IL-1β and IL-1RN are associated with CP in a Chinese population, and might be putative risk indicators for chronic periodontitis.