No abstract available.
Animals ; Mice*

No abstract available.
Animals ; Mice*

OBJECTIVE: Indoleamine 2, 3-dioxygenase (IDO), an immuno suppression enzyme, is one of the initial and rate-limiting enzymes involved in the catabolism of the essential amino acid tryptophan. IDO inhibits T cell proliferation, induces T cell apoptosis, and plays a fundamental role in autoimmunity and allergy. We investigated which subtype of dendritic cells (DCs) is involved in IDO expression and the generation of regulatory T cells during the induction of oral tolerance in type II collagen-induced arthritis (CIA). METHODS: Type II Collagen was fed to DBA/1J mice before immunization. Changes in DC subtypes and induction of regulatory T cell in orally tolerized CIA mice were analyzed. Whether the effect of DC subtype was modulated by the IDO expression, was determined by flow cytometry (FACs) and confocal microscopy. RESULTS: IDO expression of CD11c+ DCs was higher in orally tolerized CIA mice than in non-tolerized CIA mice. CD11b+ DCs of the CD11c +DCs, subtype was higher in the induction of in IDO expression. Our data suggest that these IDO expressing DCs of oral tolerized mice suppressed type II collagen-specific T cell proliferation and favored the differentiation of naive CD4+ T cells into regulatory T cells. Especially, CD11c+CD11b+ DCs expressed IDO, which is known to be associated with regulatory T cell induction. CONCLUSION: We observed that oral tolerance induced the increase in IDO-expressing CD11c+CD11b+ DCs, which appeared to induce regulatory T cells. IDO-expressing CD11c+CD11b+ DCs are involved in oral tolerance, which may provide a new therapeutic approach for the treatment of rheumatoid arthritis.
Mice ; Animals

PURPOSE: Oral mucositis induced by radiotherapy to the head and neck area, is a common acute complication and is considered as the most severe symptom for cancer patients in the early stages of treatment. This study was proposed to establish the oral mucositis mouse model induced by a single dose of radiation for the facility of testing therapeutic candidates which can be used for the oral mucositis treatments. MATERIALS AND METHODS: Fifty-five BALB/c mice were divided into four groups: control, 16 Gy, 18 Gy, and 20 Gy. Oral mucositis was induced by a single dose of radiation to the head and neck using 6 MV x-Ray from linear accelerator. After irradiation, body weight and physical abnormalities were checked daily. Tongue tissues from all groups were taken on days 1, 2, 3, 5, 7, 9, and 14, respectively and H&E staining was conducted to examine morphological changes. RESULTS: Body weight dramatically decreased after day 5 in all irradiated mice. In the 16 Gy treatment group, body weight was recovered on day 14. The histology data showed that the thickness of the epithelial cell layer was decreased by the accumulated time after radiation treatment, up to day 9. Severe ulceration was revealed on day 9. CONCLUSION: A single dose of 16 Gy is sufficient dose to induce oral mucositis in Balb/C mice. Significant changes were observed in the Balb/C mice on days 7 and 9 after radiation. It is suggested that this mouse model might be a useful standard tool for studying oral mucositis induced by radiation.
Mice ; Animals

Bone resorption involves sequential stages of osteoclast precursor migration and differen-tiation of osteoclast precursors into multinucleated osteoclasts. Stromal cell derived factor (SDF)-1 is a chemotactic factor for osteoclast precursor migration. Matrix metalloproteinase (MMP)-9 is involved in migration of osteoclast precursors and activation of interleukin(IL)-1beta. Alveolar bone destruction is a characteristic feature of periodontal disease. Treponema lecithinolyticum is a oral spirochete isolated from the periodontal lesions. The effect of lipopolysaccharide(LPS) from T. lecithinolyticum on expression of SDF-1 and MMP-9 was examined in cocultures of bone marrow cells and osteblasts derived from mouse calvariae. T. lecithinolyticum LPS increased expression of MMP-9 in the coculture. Polymyxin B, an inhibitor of LPS, abolished the increase of MMP-9 mRNA expression by LPS. LPS did not increase the expression of SDF-1, IL-1beta and tumor necrosis factor(TNF)-alpha mRNA in cocultures. Prostaglandin E2(PGE2) up-regulated the expression of MMP-9 and NS398, an inhibitor of PGE2 synthesis, down-regulated the induction of MMP-9 expression by T. lecithinolyticm LPS. These results suggest that T. lecithinolytium LPS increases MMP-9 expression in bone cells via PGE2 and that the induction of MMP-9 expression by T. lecithinolyticum LPS is involved in alveolar bone destruction of periodontitis patients by the increase of osteoclast precursor migration and the activation of bone resorption-inducing cytokine.
Mice ; Animals

Bone resorption involves sequential stages of osteoclast precursor migration and differen-tiation of osteoclast precursors into multinucleated osteoclasts. Stromal cell derived factor (SDF)-1 is a chemotactic factor for osteoclast precursor migration. Matrix metalloproteinase (MMP)-9 is involved in migration of osteoclast precursors and activation of interleukin(IL)-1beta. Alveolar bone destruction is a characteristic feature of periodontal disease. Treponema lecithinolyticum is a oral spirochete isolated from the periodontal lesions. The effect of lipopolysaccharide(LPS) from T. lecithinolyticum on expression of SDF-1 and MMP-9 was examined in cocultures of bone marrow cells and osteblasts derived from mouse calvariae. T. lecithinolyticum LPS increased expression of MMP-9 in the coculture. Polymyxin B, an inhibitor of LPS, abolished the increase of MMP-9 mRNA expression by LPS. LPS did not increase the expression of SDF-1, IL-1beta and tumor necrosis factor(TNF)-alpha mRNA in cocultures. Prostaglandin E2(PGE2) up-regulated the expression of MMP-9 and NS398, an inhibitor of PGE2 synthesis, down-regulated the induction of MMP-9 expression by T. lecithinolyticm LPS. These results suggest that T. lecithinolytium LPS increases MMP-9 expression in bone cells via PGE2 and that the induction of MMP-9 expression by T. lecithinolyticum LPS is involved in alveolar bone destruction of periodontitis patients by the increase of osteoclast precursor migration and the activation of bone resorption-inducing cytokine.
Mice ; Animals

Recently there is increasing tendency of the nosocomial infection, and Pseudomonas aeruginosa is one of the most important and common pathogens causing hospital opportunistic infections with rapid emergence of resistant strain especially in immunologically compromised patients. An experimental study for the effects of polyvalent Pseudomonas vaccine was performed in an animal model of Pseudomonas sepsis on a survival rates and histopathological points of view-using ICR inbred mice. The vaccine was prepared with heat killed whole cells of the 10 representative serotypes of Pseudomonas aeruginosa, which were isolated from the Department of Microbiology, College of Medicine, Kyung Hee University and Seoul National University, and they were devided into two polyvalent vaccine groups. The animal model of the Pseudomonas sepsis was deveoped by intravenous inoculation of Pseudomonas aeruginosa (serotype F, inoculum size 100 microliter, 109 cells/ml), immediately after cutaneous burns. The results were as follows. 1) The survival rate of the immune mice was 100% and that of non-immune mice was 60%. 2) The histologic findings of lung of the non-immune mice were severe congestion (18/18 mice), hemorrhage (18/18 mice), emphysematous change (18/18 mice), thrombosis (9/18 mice), infarction (9/18 mice) and inflammation (6/18 mice) and those of the immune mice were only congestion (6/20 mice) and focal emphysematous change (2/20) from the 3 day experimental group. 3) The histologic findings of the liver in the non-immune mice were severe congestion, Kupffer cell mobilization, focal necrosis, & portal inflammation in most of them, and from 7 day experimental group there were noted infiltrations of lagre histiocytic cells in sinusoids, and those in the immune mice were only reactive change of varying degree. 4) The histologic findings of the spleen in the non-immune mice were severe reactive hyperplasia in all and ischemic necrosis in about half of them, and those in the immune mice were only reactive change. 5) The histologic findings of the heart in the non-immune mice were severe congestion and inflammation in most and in the immune mice were only occasional nonspecific congestion. 6) The histologic findings of the kidney in the non-immune mice were severe congestion in all, interstitial inflammation, acute tubular necrosis and cortical necrosis in about half of them, and those in the immune mice were only mild congestion. With the above results, we can suspect there is a significant protective effects of the polyvalent pseudomonas vaccine on the pseudomonas sepsis in ICR mice.
Mice ; Animals

Viral myocarditis is considered an important cause of dilated cardiomyopathy. At preseent, two mechanisms are known to be involved in the pathogenesis of viral myocarditis and subse-quent cardiomyopathy: viral direct toxicity and immune mediated toxicity. Some authors have reported that IL-6 influences the immunologic mechanism and the virus-induced tissue damage in myocarditis. We injected encephalomyocarditis(EMC) virus to induce viral myocarditis in ICR mice. In order to study the lymphocyte subset and IL-6 expression to clarify the immune mechanism and to demonstrate the role of IL-6 in viral induced myocardial damage. The following results were obtained: 1) In virus inoculated mice, inflammation was severest at 10 days, and some serious complications developed, indicating a possible transition to dilated cardiomyopathy. 2) On analysis of the lymphocyte subset, CD4 cells were most prevalent at 5 days and CD8 cells were most prevalent at 10 and 20 days. 3) IL-6 was significantly increased and expression of IL-6 was constant, but its intensity was strongest at 5 days. In conclusion, IL-6, produced by inflammatory cells, fibroblasts, and endothelial cells, might play an important role in myocardial damage in experimentally induced EMC viral myocarditis by its direct cytotoxicity or cytokine mediated activation of cytotoxic cells.
Mice ; Animals

No abstract available.
Animals ; Mice*

No abstract available.
Animals ; Mice*