Division of Gastroenterology and Nutrition and EGID Centre, Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts, United States of America.
PLoS One. 2010 Aug 16;5(8):e12204. doi: 10.1371/journal.pone.0012204.
Elevated serum immunoglobulin (Ig) E is a diagnostic marker of immediate-type allergic reactions. We hypothesize that serum IgE does not necessarily reflect total body IgE because in vivo IgE can be bound to cell surface receptors such as FcepsilonRI and FcepsilonRII (CD23). The aim of this study was to analyze the relationships between levels of serum IgE, cell-bound IgE, and IgE-receptors on peripheral blood cells in a pediatric population.
Whole blood samples from 48 children (26 boys, 22 girls, mean age 10,3+/-5,4 years) were analyzed by flow cytometry for FcepsilonRI, CD23, and cell-bound IgE on dendritic cells (CD11c+MHC class II+), monocytes (CD14+), basophils (CD123+MHC class II-) and neutrophils (myeloperoxidase+). Total serum IgE was measured by ELISA and converted into z-units to account for age-dependent normal ranges. Correlations were calculated using Spearman rank correlation test.
Dendritic cells, monocytes, basophils, and neutrophils expressed the high affinity IgE-receptor FcepsilonRI. Dendritic cells and monocytes also expressed the low affinity receptor CD23. The majority of IgE-receptor positive cells carried IgE on their surface. Expression of both IgE receptors was tightly correlated with cell-bound IgE. In general, cell-bound IgE on FcepsilonRI+ cells correlated well with serum IgE. However, some patients carried high amounts of cell-bound IgE despite low total serum IgE levels.
CONCLUSION/SIGNIFICANCE: In pediatric patients, levels of age-adjusted serum IgE, cell-bound IgE, and FcepsilonRI correlate. Even in the absence of elevated levels of serum IgE, cell-bound IgE can be detected on peripheral blood cells in a subgroup of patients.
升高的血清免疫球蛋白 E(IgE)是速发型过敏反应的诊断标志物。我们假设血清 IgE 不一定反映全身 IgE,因为体内 IgE 可以与细胞表面受体如 FcepsilonRI 和 FcepsilonRII(CD23)结合。本研究旨在分析儿童人群中血清 IgE、细胞结合 IgE 和外周血细胞上 IgE 受体之间的关系。
通过流式细胞术分析 48 名儿童(26 名男孩,22 名女孩,平均年龄 10.3+/-5.4 岁)的全血样本,检测树突状细胞(CD11c+MHC Ⅱ+)、单核细胞(CD14+)、嗜碱性粒细胞(CD123+MHC Ⅱ-)和中性粒细胞(髓过氧化物酶+)上的 FcepsilonRI、CD23 和细胞结合 IgE。通过 ELISA 测量总血清 IgE,并转换为 z 单位以考虑年龄相关的正常范围。使用 Spearman 秩相关检验计算相关性。
树突状细胞、单核细胞、嗜碱性粒细胞和中性粒细胞表达高亲和力 IgE 受体 FcepsilonRI。树突状细胞和单核细胞也表达低亲和力受体 CD23。大多数 IgE 受体阳性细胞表面携带 IgE。两种 IgE 受体的表达与细胞结合 IgE 紧密相关。一般来说,FcepsilonRI+细胞上的细胞结合 IgE 与血清 IgE 相关性良好。然而,一些患者尽管血清总 IgE 水平较低,但仍存在大量细胞结合 IgE。
结论/意义:在儿科患者中,年龄调整后的血清 IgE、细胞结合 IgE 和 FcepsilonRI 水平相关。即使在血清 IgE 水平没有升高的情况下,也可以在一组患者的外周血细胞上检测到细胞结合 IgE。