Gingival beta 2-microglobulin in juvenile and chronic periodontitis.

The beta 2-microglobulin (beta 2-m) pattern in gingival biopsy specimen from 24 patients with chronic severe periodontitis (P), from 11 patients with juvenile periodontitis (JP), and from 24 periodontally healthy subjects (CO) was studied with an indirect immunoperoxidase method. No reactivity for beta 2-m was found in 71% of specimens in the P and CO groups, whereas 82% of the JP specimens showed positive beta 2-m staining in the epithelium. The reactivity was detected mostly in the upper layers of the epithelium. In all the three groups the beta 2-m reactivity was less frequent in the subepithelial connective tissue than in the epithelium proper, and it seemed to be confined to the inflammatory cells. In the JP group, prominent reactivity for beta 2-m was also located in intercellular bridges of the squamous cells. The significance of the results is discussed in terms of the cell differentiation in these diseases, including the function of beta 2-m related to the function of the classical HLA antigens (HLA-A, HLA-B, HLA-C).