Li Hong-Yun, Yao Yong-Ming, Shi Zhi-Guo, Dong Ning, Yu Yan, Lu Lian-Rong, Sheng Zhi-Yong
Department of Microbiology and Immunology, Postgraduate Medical College, 304th Hospital, Bejing, People's Republic of China.
Shock. 2003 Sep;20(3):257-63. doi: 10.1097/00024382-200309000-00010.
Staphylococcal enterotoxin B (SEB) is an important member of the superantigen family, which exerts a number of pathological effects in the human, as well as susceptible animals. The present study was conducted to observe the time course and tissue distribution of SEB in postburn Staphylococcus aureus infection; meanwhile, the relationship between SEB and multiple organ dysfunction was also studied. Eighty-six male Wistar rats were randomly divided into four groups as follows: normal control group (n = 10); scald control group (n = 10); postburn sepsis group (n = 50) in which rats inflicted with 20% total body surface area (TBSA) III degrees scald followed by SEB-producing S. aureus challenge were further divided into 0.5-, 2-, 6-, 12-, and 24-h subgroups, with 10 rats in each subgroup; and SEB monoclonal antibody (MAb) treatment group (n = 16) in which a dose of 4 mg/kg SEB MAb was given intravenously just before S. aureus challenge, and the rats were further divided into 2- and 6-h subgroups. It was found that after thermal injury combined with S. aureus infection, SEB was widely distributed to the liver, kidneys, lungs, and heart, exacerbating the pathophysiology of multiple organ dysfunction induced by postburn sepsis. At the same time, the gene and protein expressions of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) were also markedly upregulated in various tissues. Early treatment with SEB-specific MAb-MAb2D(1)-could markedly decrease SEB levels in plasma as well as in various tissues, and could significantly reduce the 6-h mortality rate (17.64% [3/17] vs. 55.6% [20/36], P = 0.02). These data suggested that neutralization of SEB is effective in ameliorating S. aureus sepsis and subsequent multiple organ damage, which might be attributed to its inhibitory effect on inflammatory mediator formation.
葡萄球菌肠毒素B（SEB）是超抗原家族的重要成员，可在人类以及易感动物中产生多种病理效应。本研究旨在观察SEB在烧伤后金黄色葡萄球菌感染中的时间进程和组织分布；同时，还研究了SEB与多器官功能障碍之间的关系。86只雄性Wistar大鼠随机分为四组：正常对照组（n = 10）；烫伤对照组（n = 10）；烧伤后脓毒症组（n = 50），该组大鼠先给予20%体表面积（TBSA）Ⅲ度烫伤，随后用产SEB的金黄色葡萄球菌攻击，再进一步分为0.5、2、6、12和24小时亚组，每组10只大鼠；以及SEB单克隆抗体（MAb）治疗组（n = 16），该组在金黄色葡萄球菌攻击前静脉注射4 mg/kg的SEB MAb，大鼠再进一步分为2和6小时亚组。结果发现，热损伤合并金黄色葡萄球菌感染后，SEB广泛分布于肝脏、肾脏、肺和心脏，加剧了烧伤后脓毒症诱导的多器官功能障碍的病理生理过程。同时，肿瘤坏死因子-α（TNF-α）和干扰素-γ（IFN-γ）在各组织中的基因和蛋白表达也明显上调。早期用SEB特异性MAb-MAb2D(1)治疗可显著降低血浆及各组织中的SEB水平，并可显著降低6小时死亡率（17.64%[3/17]对55.6%[20/36]，P = 0.02）。这些数据表明，中和SEB可有效改善金黄色葡萄球菌脓毒症及随后的多器官损伤，这可能归因于其对炎症介质形成的抑制作用。
