Neutrophil Migration Into the Gingival Sulcus Is Associated With Transepithelial Gradients of Interleukin‐8 and ICAM‐1

Abstract

The expression of adhesion molecules and the local production of chemotactic cytokines within the epithelium are considered to be key events in neutrophil (PMN) migration at sites of mucosal infections. In their journey toward the gingival sulcus, PMNs have been shown to selectively migrate through the junctional epithelium. Little, however, is known about the molecular mechanisms involved in this key process aimed at the control of subgingival bacterial plaque. This investigation describes the expression of IL‐8 mRNA‐positive cells and the establishment of a gradient of intercellular adhesion molecule‐1 (ICAM‐1) receptors within the junctional epithelium of clinically healthy gingiva. Expression of ICAM‐1 and IL‐8 was topographically associated with the area of PMN migration; i.e., the junctional epithelium. Levels of ICAM‐1 expression increased from the basal cells toward the surface of the junctional epithelium and thus toward areas exposed to bacterial challenges. IL‐8 mRNA‐positive cells were also present at highest density in the most superficial junctional epithelial layers. The combination of the haptotactic stimuli, resulting from the interaction of the PMN's β2 integrin receptors with the gradient of ICAM‐1 expression, and the location of IL‐8 mRNA‐positive cells, consistent with the establishment of a discrete PMN chemotactic source, may play an important physiologic role in efficiently routing PMNs to the gingival sulcus. This process contributes to the maintenance of a local host‐parasite equilibrium and to the limitation of PMN‐associated tissue damage. J Periodontol 1998;69:1139–1147.

Interactions between the Aggregatibacter actinomycetemcomitans secretin HofQ and host cytokines indicate a link between natural competence and interleukin-8 uptake

“…However, in periodontitis, this IL-8 gradient fades, debilitating the host response to potential pathogens [42,43]. In naturally competent A. actinomycetemcomitans strains capable of boosting IL-8 sequestration by linking it to DNA uptake, this process may have a role in weakening the host defense in a manner similar to that described above.…”

Activation of human gingival epithelial cells by cell-surface components of black-pigmented bacteria: augmentation of production of interleukin-8, granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor and expression of intercellular adhesion molecule 1

“…These accumulated cells might express LFA-1 on their cell surface and attach to epithelial cells via ICAM-1 and LFA-1 interaction, then in®ltrate into the gingival epithelium [8,27]. In fact, ICAM-1 and IL-8 mRNA expression are topographically associated with the area of neutrophil migration in the junctional epithelium [31]. IL-8-activated neutrophils show a respiratory burst to produce superoxide [30].…”

Impact of Dental Plaque Biofilms in Periodontal Disease: Management and Future Therapy

“…Expression of mediators such as interleukin 8 (IL-8), intercellular adhesion molecule (ICAM), E-selectin and β defensin molecules 1, 2 and 3 are required to form this neutrophil defense wall [64][65][66]. E-selectin is required for neutrophil migration from the highly vascularized gingival tissue, IL-8 is a key neutrophil chemo-attractant produced by epithelial cells, and ICAM facilitates adhesion of neutrophils to the tissue allowing formation of this wall [67,68].…”