Mi. Gazi et al., COMPARISON OF HOST TISSUE AND BACTERIAL DIPEPTIDYL PEPTIDASES IN HUMAN GINGIVAL CREVICULAR FLUID BY ANALYTICAL ISOELECTRIC-FOCUSING, Archives of oral biology, 40(8), 1995, pp. 731-736
Earlier work has shown that gingival crevicular fluid (GCF) contains d
ipeptidyl peptidase (DPP) activities that resemble those in host tissu
e. Here, further comparisons were made with enzymes from suspected per
iodontal pathogens. Gingival tissue and GCF were collected from patien
ts with chronic periodontitis. DPP II and DPP IV fractions with acid a
nd alkaline pH optima, respectively, were separated from crude tissue
extracts by gel-filtration chromatography. Bacterial cell sonicates we
re prepared from broth cultures of reference strains. There was modera
te to strong DPP activity with Capnocytophaga spp., Porphyromonas ging
ivalis and Prevotella spp., very weak activity with Treponema denticol
a and no detectable activity with Actinobacillus actinomycetemcomitans
or Fusobacterium nucleatum. Banding patterns in GCF, tissue and bacte
rial samples were compared on substrate-impregnated overlay membranes
applied to isoelectric focusing gels. In gels washed with acid buffer,
GCF had bands corresponding to tissue DPP II. Use of an alkaline wash
ing buffer showed GCF activity which closely matched tissue DPP IV tha
t had been pretreated with neuraminidase, an enzyme found by others in
the gingival crevice. P. gingivalis gave multiple bands and several o
f these had counterparts in GCF. The apparent presence in GCF of the D
PP from P. gingivalis is consistent with the association of this organ
ism with destructive periodontitis.