Sarvas H, Seppälä I, Kurikka S, Siegberg R, Mäkelä O
Department of Bacteriology and Immunology, University of Helsinki, Finland.
J Clin Immunol. 1993 Mar;13(2):145-51. doi: 10.1007/BF00919271.
The residence time of maternal IgG1 in the circulation of infants was measured by monitoring f-allotypic IgG1 or f-positive tetanus toxoid antibody in genetically G1mf-negative infants. G1ma-positive maternal tetanus toxoid antibody was similarly monitored in genetically a-negative infants. Blood samples were taken from infants at the age of 1-3 days, ca. 4 months, and ca. 6 months. An exponential decay at the same rate took place from age 1-3 days to 4 months and for the 2 subsequent months. The average concentration of the maternal IgG1 had dropped to ca. 10% of the 1- to 3-day value in 4 months and to ca. 3% in 6 months. The drop was due mainly to clearance but partly also to the weight increase of the child (doubling in 6 months). By correcting for the weight increase, we calculated that ca. 17 and 7% of the original maternal IgG1 was still present at ages 4 and 6 months, respectively. The average half-life of the maternal IgG1 was thus 48.4 days. The concentration of endogenous IgG1 in the cord blood was determined by studying a separate series of mother-newborn pairs. Assuming that cross-reactions of antiallotype reagents had no effect, the highest measured concentration of f-positive IgG1 in infants of f-negative mothers was 10 mg/L, half a percent of adult heterozygote values. Crossreaction may have played a role, however, and the value must be considered the upper limit of the true concentration.
通过监测基因G1mf阴性婴儿体内的f-异型IgG1或f阳性破伤风类毒素抗体，来测定母体IgG1在婴儿循环系统中的停留时间。在基因a阴性婴儿中同样监测了G1ma阳性母体破伤风类毒素抗体。在婴儿1 - 3天、约4个月和约6个月时采集血样。从1 - 3天到4个月以及随后的2个月中，均以相同速率呈指数衰减。4个月时，母体IgG1的平均浓度降至1 - 3天值的约10%，6个月时降至约3%。这种下降主要是由于清除，但部分也是由于儿童体重增加（6个月内翻倍）。通过校正体重增加，我们计算得出，在4个月和6个月时，分别仍有大约17%和7%的母体原始IgG1存在。因此，母体IgG1的平均半衰期为48.4天。通过研究另一系列母婴对来测定脐带血中内源性IgG1的浓度。假设抗异型试剂的交叉反应没有影响，f阴性母亲的婴儿中测得的f阳性IgG1的最高浓度为10 mg/L，是成人杂合子值的0.5%。然而，交叉反应可能起到了作用，该值必须被视为真实浓度的上限。
