Immunoglobulin G response of periodontitis patients to Porphyromonas gingivalis capsular carbohydrate and lipopolysaccharide antigens

Abstract

Porphyromonas gingivalis clonal types that participate in periodontal infections express serologically distinct surface antigens. This investigation sought to determine whether serum antibodies titers against the serotype-specific capsular carbohydrate K antigen and lipopolysaccharide antigens of P. gingivalis might reveal which serotypes are most likely to be responsible for subgingival infections in subjects with adult periodontitis. Immunoglobulin G (IgG) titers to purified K antigen and lipopolysaccharide from different P. gingivalis strains were measured by ELISA for 28 healthy controls and 51 patients with periodontal pockets known to be infected with genetically and serologically distinct P. gingivalis clonal types. Titers to purified K antigen from strains W50, HG184, A7A1-28, 49417, HG1690 and HG1691, representing serotypes K1-K6, respectively, and lipopolysaccharide from strains 381, HG1691 and W50, representing serotypes O1-O3, respectively, were measured for all subjects. Chi-square likelihood ratios, Mann-Whitney tests and receiver-operating characteristic sensitivity-specificity plots were used to compare the accuracy with which titer results for different target antigens classified subjects with or without disease. Results from assays targeting K2, K3, K4, K5, O1 and O2 generally gave poor diagnostic accuracy, whether evaluated separately or as summed titer pairs corresponding to the K/O combinations actually expressed by the target antigen parent strains. Exceptions were O3 (from W50) and K5+O2 (both from HG1690), which gave moderate accuracy in classifying subjects. In contrast, highly significant diagnostic accuracy was achieved using individual K1 (W50) and K6 (HG1691) titer data and K1+O3 (W50) and K6+O2 (HG1691) titer sum values. These observations suggest that P. gingivalis clonal types expressing K/O serotypes matching those of W50 (K1/O3) and HG1691 (K6/O2) are more likely than others to participate in periodontal infections in adult periodontitis patients and thus are more likely than others to express relevant virulence factors.

Immunization withPorphyromonas gingivalisCapsular Polysaccharide PreventsP. gingivalis-Elicited Oral Bone Loss in a Murine Model

“…Humans with periodontal disease produce P. gingivalis CPSspecific IgG (4,32). Despite reports of elevated levels of P.…”

“…lis capsule serotypes have been defined; however, serologic assessments of periodontitis patients suggest that additional P. gingivalis CPS-specific serotypes exist (4,20,32).…”

Deletion of a 77-Base-Pair Inverted Repeat Element Alters the Synthesis of Surface Polysaccharides in Porphyromonas gingivalis

“…Both K-antigen capsule and LPS account for the serotype specificity of a particular strain. To date, three different O-antigen serotypes and at least six K-antigen serotypes of P. gingivalis have been identified (16,17).…”

Porphyromonas gingivalis infection in gestational diabetes mellitus and survival in tobacco smokers.

“…Six different serotypes of capsules have been identified depending on capsular polysaccharide Kantigens and their capacity to generate systemic IgG antibodies [104]. Bacterial encapsulation is positively correlated with increased resistance to phagocytosis [105].…”