Hennessey P J, Black C T, Andrassy R J
Department of Surgery, University of Texas Medical School, Houston, Texas 77030.
JPEN J Parenter Enteral Nutr. 1991 Jan-Feb;15(1):60-4. doi: 10.1177/014860719101500160.
Transient hyperglycemia in patients receiving total parenteral nutrition may be associated with impaired immune function. The effects of short-term hyperglycemia on one aspect of antimicrobial immune function, ie, the ability of IgG to fix complement, were investigated. Aliquots of anti-human albumin, anti-horse ferritin, and anti-alkaline phosphatase were incubated for 0, 8, 16, 24, 48, and 96 hr with either 0 or 240 mg of glucose per deciliter of buffer. All samples were analyzed for the degree of glycation using a thiobarbituric acid assay, and for complement fixation ability using a microcomplement fixation assay. Significant increases in glycation over control samples were observed after only 16 hr (31 vs 15 mmol 5-hydroxymethylfurfural/mol IgG, p less than 0.01). Complement fixation was significantly altered after 48 hr of incubation (76 +/- 5% vs 90 +/- 8% total serum complement fixed by albumin/anti-albumin complex, p less than 0.03) when four of the 84 (4.7%) IgG lysine residues were glycated. It is demonstrated that a significant reduction in complement fixation by immunoglobulin occurs with elevated glucose concentrations and that this may play a clinically significant role in transiently hyperglycemic patients.
接受全胃肠外营养的患者出现的短暂高血糖可能与免疫功能受损有关。研究了短期高血糖对抗菌免疫功能的一个方面，即IgG固定补体能力的影响。将抗人白蛋白、抗马铁蛋白和抗碱性磷酸酶的等分试样在每分升缓冲液含0或240毫克葡萄糖的条件下分别孵育0、8、16、24、48和96小时。所有样品均使用硫代巴比妥酸测定法分析糖基化程度，并使用微量补体固定测定法分析补体固定能力。仅在16小时后就观察到糖基化相对于对照样品有显著增加（31对15 mmol 5-羟甲基糠醛/摩尔IgG，p小于0.01）。当84个（4.7%）IgG赖氨酸残基中的4个发生糖基化时，孵育48小时后补体固定发生显著改变（白蛋白/抗白蛋白复合物固定的总血清补体为76±5%对90±8%，p小于0.03）。结果表明，随着葡萄糖浓度升高，免疫球蛋白的补体固定能力显著降低，这可能在短暂高血糖患者中发挥临床重要作用。
