Project/Area Number |
04807049
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
Gastroenterology
|
Research Institution | Tokyo Medical and Dental University |
Principal Investigator |
OHKUSA Toshifumi First Department of Internal Medicine M.D., 医学部, 助手 (50160445)
|
Co-Investigator(Kenkyū-buntansha) |
TOKOI Shinsuke Fitst Department of Internal Medicine, 医学部, 医員
|
Project Period (FY) |
1992 – 1993
|
Project Status |
Completed (Fiscal Year 1993)
|
Budget Amount *help |
¥2,200,000 (Direct Cost: ¥2,200,000)
Fiscal Year 1993: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 1992: ¥1,000,000 (Direct Cost: ¥1,000,000)
|
Keywords | Ulcerative Colitis / Bacterial culture of the Mucosa / Intestinal Microflora / Vero toxin / Experimental Ulcerative Colitis / Dextran Sulfate Sodium / Macrophage / Immunoglobulin / コレラ菌毒素 / 粘膜局所墓免疫 / 腸内細菌 |
Research Abstract |
We investigated interactions berween mucosal lesions and bacterial invasion in ulcerative colitis using the acridine-orange staining method. In all 16 cases of ulcerative colitis, the mucosa was found to be invaded by small rods. In 5 of 10 controls, bacteria were seen only adhering to the mucosa and no bacteria were detected in the 5 remaining cases. It is suggested that the presence of bacteria in the colonic mucosa seems to be concerned with the persistence and aggravation of the mucosal lesion of ulcerative colitis. We previously reported that numerous macrophages which phagocytosed dextran sulfate sodium were observed to have accumulated in the mucosal lesions and in the spleen in experimental ulcerative colitis induced in mice with dextran sulfate sodium. In this paper, we investigated the bacterial phagocytic abitity of macrophages which were isolated from spleens of mice treated with 3% dextran sulfate sodium for 6 months. In this model, the number of phagocytosed bacteria (Listeria monocytogenes) and the phagocytic index were significantly decreased. The phagocytic ability of splenic macrophages obtained from non-treated mice was also evaluated by incubating with dextran sulfate sodium in vitro, and adding bacteria. The number of phagocytosed bacteria and the phagocytic index were also signigicantly decreased. These observations suggest that the decrease in bacterial phagocytosis in this model by macrophages that phagocytosed dextran sulfate sodium indicates a decline of the mucosal defense system to bacteria.
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