Localization of the chemokine interleukin-8 and interleukin-8 receptors in human gingiva and cultured gingival keratinocytes.
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.
Sfakianakis
Andreas
A
Department of Periodontology, University of Connecticut, School of Dental Medicine, Farmington 06030-3105, USA.
Barr
Charles E
CE
Kreutzer
Don L
DL
D000328:Adult; D000368:Aged; D000906:Antibodies; D002465:Cell Movement; D002478:Cells, Cultured; D004396:Coloring Agents; D004730:Endothelium, Vascular / Q000276:immunology / Q000473:pathology; D004848:Epithelium / Q000276:immunology / Q000473:pathology; D005260:Female; D005881:Gingiva / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D016209:Interleukin-8 / Q000032:analysis*; D015603:Keratinocytes / Q000276:immunology* / Q000473:pathology; D007962:Leukocytes / Q000276:immunology / Q000473:pathology; D008297:Male; D008833:Microcirculation / Q000276:immunology / Q000473:pathology; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000276:immunology / Q000473:pathology; D010518:Periodontitis / Q000276:immunology / Q000473:pathology; D023062:Receptors, Interleukin-8A / Q000032:analysis*; D023063:Receptors, Interleukin-8B / Q000032:analysis*
D000906:Antibodies; D004396:Coloring Agents; D016209:Interleukin-8; D023062:Receptors, Interleukin-8A; D023063:Receptors, Interleukin-8B