Ambrosino D M, Black C M, Plikaytis B D, Reimer C B, Lee M C, Evatt B L, Carlone G M
Laboratory of Infectious Diseases, Dana-Farber Cancer Institute, Boston, Massachusetts.
J Pediatr. 1991 Dec;119(6):875-9. doi: 10.1016/s0022-3476(05)83036-7.
To determine whether IgG subclass concentrations differed between healthy black and white children, we measured IgG1, IgG2, IgG3, and IgG4 immunoglobulins by enzyme-linked immunosorbent assay in sera from 246 black children aged 6 to 42 months. We then compared these values with the normal values established for 664 white children aged 6 to 60 months. The IgG1, IgG2, and IgG4 subclass concentrations of the black children were lower than those for white children; many of the values were below the 95% confidence limits established for white children: 46 (19%) of 246 IgG2 values and 19 (8%) of 246 IgG4 values for black children were below the normal limits. We compared the geometric mean values for black and white children, as determined for each 6-month age grouping between 6 and 42 months of age; 367 of the 664 white children were less than 42 months of age and were included in this analysis. The geometric mean values for IgG1, IgG2, and IgG4 levels were consistently lower for black children than for white children. The differences were significant for IgG1 subclass values of those children older than 24 months and for IgG2 and IgG4 values of those children older than 18 months. No consistent differences were noted for IgG3 subclass values. We conclude that young black children have lower IgG1, IgG2, and IgG4 serum concentrations than are found in white children. If normal IgG values for white children are used, healthy black children may be erroneously classified as IgG subclass deficient. The mechanism and biologic relevance of these population differences need to be evaluated.
为了确定健康的黑人儿童与白人儿童之间的IgG亚类浓度是否存在差异，我们采用酶联免疫吸附测定法对246名6至42个月大的黑人儿童血清中的IgG1、IgG2、IgG3和IgG4免疫球蛋白进行了测量。然后，我们将这些值与为664名6至60个月大的白人儿童确定的正常值进行了比较。黑人儿童的IgG1、IgG2和IgG4亚类浓度低于白人儿童；许多值低于为白人儿童确定的95%置信限：246个黑人儿童的IgG2值中有46个（19%）和IgG4值中有19个（8%）低于正常限。我们比较了6至42个月龄之间每6个月年龄分组的黑人儿童与白人儿童的几何平均值；664名白人儿童中有367名年龄小于42个月，被纳入该分析。黑人儿童的IgG1、IgG2和IgG4水平的几何平均值始终低于白人儿童。对于24个月以上儿童的IgG1亚类值以及18个月以上儿童的IgG2和IgG4值，差异具有统计学意义。未发现IgG3亚类值有一致的差异。我们得出结论，年幼的黑人儿童血清中IgG1、IgG2和IgG4的浓度低于白人儿童。如果使用白人儿童的正常IgG值，健康的黑人儿童可能会被错误地归类为IgG亚类缺乏。这些人群差异的机制和生物学相关性需要进行评估。
