Localization of the chemokine interleukin-8 and interleukin-8 receptors in human gingiva and cultured gingival keratinocytes

• Published in: Journal of periodontal research 2002-04, Vol.37 (2), p.154-160
• Main Authors: Sfakianakis, Andreas, Barr, Charles E., Kreutzer, Don L.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Antibodies; Biological and medical sciences; Cell Movement; Cells, Cultured; Coloring Agents; Dentistry; Endothelium, Vascular - immunology; Endothelium, Vascular - pathology; Epithelium - immunology; Epithelium - pathology; Facial bones, jaws, teeth, parodontium: diseases, semeiology; Female; Gingiva - immunology; Gingiva - pathology; Humans; Immunoenzyme Techniques; Immunohistochemistry; interleukin-8; Interleukin-8 - analysis; interleukin-8 receptors; Keratinocytes - immunology; Keratinocytes - pathology; Leukocytes - immunology; Leukocytes - pathology; Male; Medical sciences; Microcirculation - immunology; Microcirculation - pathology; Middle Aged; Muscle, Smooth, Vascular - immunology; Muscle, Smooth, Vascular - pathology; Non tumoral diseases; Otorhinolaryngology. Stomatology; periodontitis; Periodontitis - immunology; Periodontitis - pathology; Receptors, Interleukin-8A - analysis; Receptors, Interleukin-8B - analysis
• ISSN: 0022-3484; 1600-0765
• DOI: 10.1034/j.1600-0765.2002.00024.x

Interleukin‐8 (IL‐8) has been implicated in a wide variety of diseases. Previous studies have demonstrated the expression of IL‐8 in periodontal tissues, yet little is known about the exact source(s), mechanisms and factors involved in gingival expression of IL‐8. Additionally, nothing is known about the presence and distribution of IL‐8 receptors (IL‐8R) in gingival cells. Therefore it was hypothesized that, in vivo, periodontal pathogens induce IL‐8 expression from gingival keratinocytes (GK) which enhances leukocyte, microvascular endothelial cell (MVEC) and GK migration via specific IL‐8 receptors present on these cells. The objective of the present study was to determine the distribution of IL‐8 and IL‐8R in gingival tissues and cultured human GK in vitro. Standard immunohistochemical and immunocytochemical techniques were utilized in order to localize IL‐8 and its receptors CXCR‐1 and CXCR‐2 in archival gingival specimens (eight periodontitis and four non‐inflamed controls) and in cultured gingival keratinocytes. It was demonstrated that, in vivo, IL‐8 and IL‐8R were present in gingival epithelium, MVEC and leukocytes. In vitro studies verified the above results, by showing expression of IL‐8 and IL‐8R in cultured gingival keratinocytes. It is concluded that IL‐8 and IL‐8 receptors are expressed in gingival epithelium both in vivo and in vitro. This new evidence indicates that epithelium plays a critical role in the host defense against invading pathogens and that keratinocytes can actively respond to IL‐8 and other host cytokines, via specific receptors.