The glycoproteins, desmogleins 2 and 3 (desmocollins) are integral to the formation, assembly and stability of desmosomes. The formation of desmosomes is inhibited by Fab fragments of antibodies against desmogleins 2 and 3. The N-termini of desmogleins 2 and 3 are implicated directly in the adhesion of hemi-desmosomes and establish and maintain epithelial cell-cell contact. Epithelial cell-cell contact requires desmosomal integrity, which must be maintained in periodontal health. Elevated titers of naturally occurring antibodies against desmosomal proteins in the gingiva, we hypothesize, would contribute to the proliferation of the epithelial attachment, a key sign of periodontitis. Indeed, patients with periodontitis, in a preliminary study, do show more naturally occurring IgG serum and gingival crevicular fluid (GCF) antibodies against desmosomal proteins than healthy individuals. Unfortunately, no quantitative assay exists for antibodies against the N-terminus of desmogleins 2 and 3 because of the insolubility of desmosomes and the incumbent difficulty in protein isolation. Using a peptide synthesized from information inferred from desmoglein 2 and 3 CDNA, our aim is to quantify antibody against N-terminal peptide of desmogleins 2 and 3 in serum and gingival crevicular fluid with a new ELIZA assay. This assay and the monospecific antibodies developed will then be used in a cross-sectional study of healthy and periodontitis subjects. The long term goal is to study the dynamics of the desmosomal proteins during periodontitis.