Interleukin‐1 receptor antagonist and interleukin‐4 in gingival crevicular fluid of patients with inflammatory periodontal disease

Interleukin-1 receptor antagonist (IL-1ra) and interleukin-4 (IL-4) were detected in gingival crevicular fluid (GCF) by an immunochemical method. However, we could not detect IL-4 in GCF from severe inflammation sites. In addition, we sought to detect which cells had produced cytokines in moderately inflamed gingival tissues by means of immunohistochemistry. The cell types expressing CD 68 were identified as monocytes/macrophages and stained positively for IL-1ra. The helper T cells identified by immunostaining for CD 4 stained positively for IL-4. These results suggest that IL-4 is one of the mediators regulating the degree of local inflammation in periodontal disease.