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In Situ Detection of Bacteria within Paraffin-embedded Tissues Using a Digoxin-labeled DNA Probe Targeting 16S rRNA
Published on: May 21, 2015
Characterization of Aggregatibacter actinomycetemcomitans strains in periodontitis patients in Germany
Holger Jentsch1, Georg Cachovan, Arndt Guentsch
1Department of Conservative Dentistry and Periodontology, Medical Faculty, University of Leipzig, Nürnberger Str. 57, 04103 Leipzig, Germany. jenh@medizin.uni-leipzig.de
Objectives:
Aggregatibacter actinomycetemcomitans strains of serotype b and with a deletion of 530 bp in the promoter region of the leukotoxin gene (JP2 clone) are known to be associated with severe periodontitis. Our study was aimed to detect virulence genes of A. actinomycetemcomitans strains obtained from patients living in four German cities with different proportions of immigrants.
Material And Methods:
Samples were obtained from severe periodontitis patients in Frankfurt, Hamburg, Leipzig, and Jena. Those being tested positive for A. actinomycetemcomitans were analyzed for serotypes, deletion in the promoter region of the leukotoxin gene, presence of cytolethal distending toxin encoding genes (cdtA, cdtB, and cdtC) and fibril gene1(flp-1).
Results:
From all 99 A. actinomycetemcomitans-positive samples, the JP2 clone was found in two immigrants in Frankfurt. Seventy strains were tested positive for the cdtA, 52 for cdtB, and 92 for cdtC and flp-1 genes. Twenty-five strains belonged to serotype a, 22 to serotype b, 21 to serotype c, 31 to the others or could not be serotyped, respectively. The distribution of the serotypes differed between the cities. Further, differences regarding the serotypes were also significant between natives and immigrants.
Conclusions:
The JP2 clone is not spread within the Caucasian inhabitants in German cities. The serotypes distribution seems to be influenced by the numbers of immigrants in the cities.
Clinical Relevance:
Patients originated from North Africa should be especially screened for the presence of the deletion in the ltx promoter region.
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