Departmental Papers (Dental)

Document Type

Journal Article

Date of this Version


Publication Source

Journal of Medical Microbiology




Pt. 8

Start Page


Last Page





The periodontal pathogen Actinobacillus actinomycetemcomitans expresses a cytolethal distending toxin (CDT) that typically arrests the growth of eukaryotic cells at either the G0/G1 or G2/M phase of the cell cycle. It was previously found that CDT failed to arrest the growth of human periodontal ligament fibroblasts (HPLFs) when grown in pure culture. In contrast, proliferation of an oral epithelial cell line was rapidly inhibited by the toxin. In this study, the feasibility of using mixed-cell cultures and cell-specific markers to evaluate the response of oral cells, when in heterogeneous populations, to CDT was established. Proliferation of epithelial cells was rapidly inhibited and the cells were selectively eliminated in co-culture with HPLFs or cementoblasts by 24–48 h post-intoxication. Epithelial cells and HPLFs were detected and counted in co-cultures following cell-specific immunolabelling with antibodies against simian virus 40 large T antigen and the Ab-1 surface antigen, respectively. These results demonstrated that the activities of potential virulence factors, such as CDT, from periodontal pathogens can be successfully examined in mixed-cell cultures. This approach is especially relevant to infectious diseases that affect tissues with a diverse cellular composition, such as the periodontium.

Copyright/Permission Statement

© [Kang, P., Korostoff, J.,Volgin, A., Grzesik, W., and DiRienzo, J.M., 2005]. The definitive peer reviewed, edited version of this article is published in [Journal of Medical Microbiology, 54, pt.8, 2005, 10.1099/jmm.0.46077-0].

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Dentistry Commons



Date Posted: 01 March 2022

This document has been peer reviewed.