ABSTRACT
OBJECTIVE@#Calprotectin, the heterdimer of S100A8 and S100A9, is the major cytoplasmic protein of neutrophils, which is also expressed or induced in gingival epithelial cells, activated mononuclear macrophages and vascular endothelial cells. Calprotectin is intimately associated with the initiation and progression of periodontitis, but the in vivo expression patterns of calprotectin in healthy and inflamed periodontal tissue are not fully understood. To observe the expression, distribution and cellular localization of calprotectin in the samples of healthy periodontal tissues and experimental periodontitis tissues of Beagles and to explore their relationship with periodontal inflammation and possible effect.@*METHODS@#Experimental periodontitis model was established by ligation around the mandibular second molar of the Beagle dogs, while the contralateral teeth were healthy controls. Induction duration was 12 weeks, before the dogs were executed. Tissue specimens were demineralized and serial sections were made conventionally. The in vivo expression of calprotectin in the healthy and inflamed periodontal tissues were examined by immunohistochemistry. The in vitro expression of calprotectin in human primary gingival fibroblasts (GFs) and periodontal ligament (PDL) cells were detected by immunocytochemistry.@*RESULTS@#Immunohistochemistry analysis indicated that calprotectin was expressed in gingival epithelial cells and infiltrated neutrophils in the healthy periodontium within the gingival epithelium, S100A8/A9 was most strongly expressed in the junctional epithelium, followed by surface epithelium, and least expressed in the sulcular epithelium. The S100A8/A9 expression levels were sharply defined at the junction between the junctional epithelium and the sulcular epithelium. In periodontal inflammatory lesions, the expression level of calprotectin in sulcular epithelium and junctional epithelium was up-regulated than that in the healthy gingival epithelium. Calprotectin was inducibly expressed in fibroblast-like cells in gingival connective tissue and periodontal ligament tissue, microvascular endothelial cells (ECs) and bone marrow fibroblasts under inflammatory conditions. Additionally, the expression of calprotectin in primary human GFs and PDL cells was confirmed by immunnocytochemistry staining.@*CONCLUSION@#Constitutively expressed in neutrophils and gingival epithelial cells, and calprotectin might maintain the homeostasis and integrity of periodontium. Inflammation-induced expression of calprotectin in GFs, PDL cells, microvascular ECs and bone marrow fibroblasts might process anti-microbial function and promote leukocytes transmigration to defend the host against the microorganisms.
Subject(s)
Animals , Dogs , Humans , Endothelial Cells , Epithelial Attachment , Gingiva , Leukocyte L1 Antigen Complex , PeriodontiumABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of minocycline hydrochloride ointment on cell attachment and proliferation on titanium disks.</p><p><b>METHODS</b>Commercially pure (grade 4) machined titanium discs with three different kinds of surfaces (smooth, acid-etched and sandblasted combined with acid-etched) were treated with minocycline ointment for 1 week, and then cleaned in ultrasonic cleanser for 10 minutes. Surface properties were examined by scanning electron microscope (SEM) and roughness tester before and after the treatment. Surface roughness was compared by paired t test. MG-63 (human osteoblast-like osteosarcoma cell) cells were seeded on these three kinds of discs with or without minocycline treatment, and methl thiazolyl tetrazolium (MTT) was performed to investigate the attachment in the 1st day and proliferation in the 4th and 7th day. Data were analyzed by double factor analysis of variance.</p><p><b>RESULTS</b>Surface roughness before and after minocycline application was as follows, Smooth: (0.093 ± 0.025) µm, (0.086 ± 0.026) µm; Acid-etched: (1.100 ± 0.095) µm, (1.009 ± 0.196) µm; Sandblasted combined with acid-etched: (2.837 ± 0.283) µm, (2.968 ± 0.206) µm. No significant changes in roughness were found before and after minocycline application (P values were 0.118, 0.436 and 0.692). SEM examination revealed as similar surface configuration after minocycline application as before, except for some remnant of the minocycline ointment in acid-etched and sandblasted combined acid-etched groups. In MTT test, the growth of MG-63 cells in the 1 st, 4th day and 7th day was not different between groups with and without minocycline application (P values were 0.450, 0.848 and 0.835), and among three groups of different surface (P values were 0.184, 0.579 and 0.331).</p><p><b>CONCLUSIONS</b>Minocycline hydrochloride ointment did not affect the surface configuration, surface roughness or the properties for cell attachment and proliferation of titanium discs.</p>