Abstract | UNLABELLED: INTRODUCTION: MATERIALS AND METHODS: Actinobacillus actinomycetemcomitans 29-kDa outer membrane protein-specific Th1-clone cells were used to evaluate the expression of Kv1.3 (using reverse transcriptase-polymerase chain reaction [RT-PCR] and Western blot analyses) and the effects of the potassium channel blocker kaliotoxin (0-100 nM) on T-cell activation parameters ([3H] thymidine incorporation assays and ELISA) and expression of RANKL and osteoprotegerin (OPG; flow cytometry, Western blot, and RT-PCR analyses). A rat periodontal disease model based on the adoptive transfer of activated 29-kDa outer membrane protein-specific Th1 clone cells was used to analyze the effects of kaliotoxin in T-cell-mediated alveolar bone resorption and RANKL and OPG mRNA expression by gingival T-cells. Stimulated 29-kDa outer membrane protein-specific Th1 clone cells were transferred intravenously on day 0 to all animals used in the study (n = 7 animals per group). Ten micrograms of kaliotoxin were injected subcutaneously twice per day on days 0, 1, 2, and 3, after adoptive transfer of the T-cells. The control group of rats was injected with saline as placebo on the same days as injections for the kaliotoxin-treated group. The MOCP-5 osteoclast precursor cell line was used in co-culture studies with fixed 29-kDa outer membrane protein-specific Th1-clone cells to measure T-cell-derived RANKL-mediated effects on osteoclastogenesis and resorption pit formation assays in vitro. Statistical significance was evaluated by Student's t-test. RESULTS:
Kaliotoxin decreased T-cell activation parameters of 29-kDa outer membrane protein-specific Th1 clone cells in vitro and in vivo. Most importantly, kaliotoxin administration resulted in an 84% decrease of the bone resorption induced in the saline-treated control group. T-cells recovered from the gingival tissue of kaliotoxin-treated rats displayed lower ratios of RANKL and OPG mRNA expression than those recovered from the control group. The ratio of RANKL and osteoprotegerin protein expression and induction of RANKL-dependent osteoclastogenesis by the activated T-cells were also markedly decreased after kaliotoxin treatments in vitro. CONCLUSION:
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Authors | Paloma Valverde, Toshihisa Kawai, Martin A Taubman |
Journal | Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research
(J Bone Miner Res)
Vol. 19
Issue 1
Pg. 155-64
(Jan 2004)
ISSN: 0884-0431 [Print] United States |
PMID | 14753747
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Bacterial Outer Membrane Proteins
- CD3 Complex
- Carrier Proteins
- Glycoproteins
- Immunoglobulin G
- Isoenzymes
- Kcna3 protein, rat
- Kv1.3 Potassium Channel
- Lipopolysaccharides
- Membrane Glycoproteins
- Omp29 protein, Actinobacillus actinomycetemcomitans
- Osteoprotegerin
- Potassium Channels
- Potassium Channels, Voltage-Gated
- RANK Ligand
- Receptors, Cytoplasmic and Nuclear
- Receptors, Tumor Necrosis Factor
- Scorpion Venoms
- Tnfrsf11b protein, rat
- kaliotoxin
- Interferon-gamma
- Acid Phosphatase
- Tartrate-Resistant Acid Phosphatase
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Topics |
- Acid Phosphatase
(analysis)
- Adoptive Transfer
- Aggregatibacter actinomycetemcomitans
(chemistry)
- Alveolar Bone Loss
(drug therapy, immunology, physiopathology)
- Animals
- Antigen Presentation
(drug effects, immunology)
- Bacterial Outer Membrane Proteins
(immunology, pharmacology)
- Blotting, Western
- CD3 Complex
(immunology)
- Carrier Proteins
(genetics, metabolism)
- Cell Differentiation
(drug effects, immunology)
- Coculture Techniques
- Down-Regulation
(immunology, physiology)
- Female
- Gene Expression
- Glycoproteins
(genetics, metabolism)
- Immunoglobulin G
(blood)
- Interferon-gamma
(metabolism)
- Isoenzymes
(analysis)
- Kv1.3 Potassium Channel
- Lipopolysaccharides
(pharmacology)
- Lymphocyte Activation
(drug effects)
- Maxilla
(pathology)
- Membrane Glycoproteins
(genetics, metabolism)
- Osteoclasts
(immunology, physiology)
- Osteoprotegerin
- Periodontitis
(drug therapy, immunology, physiopathology)
- Potassium Channels
(drug effects, genetics, physiology)
- Potassium Channels, Voltage-Gated
(antagonists & inhibitors)
- RANK Ligand
- Rats
- Receptors, Cytoplasmic and Nuclear
(genetics, metabolism)
- Receptors, Tumor Necrosis Factor
- Scorpion Venoms
(pharmacology)
- Spleen
(cytology)
- T-Lymphocytes
(immunology, transplantation)
- Tartrate-Resistant Acid Phosphatase
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