Allergy and Clinical Immunology Section, Department of Leukocyte Biology, Division of National Heart and Lung Institute, Imperial College London, and MRC & Asthma UK Centre in Allergic Mechanisms of Asthma, London, United Kingdom; Immunomodulation and Tolerance Group, Allergy and Clinical Immunology Section, Department of Leukocyte Biology, Imperial College London, London, United Kingdom.
Allergy and Clinical Immunology Section, Department of Leukocyte Biology, Division of National Heart and Lung Institute, Imperial College London, and MRC & Asthma UK Centre in Allergic Mechanisms of Asthma, London, United Kingdom.
J Allergy Clin Immunol. 2015 Apr;135(4):913-921.e9. doi: 10.1016/j.jaci.2014.09.049. Epub 2014 Nov 22.
Immunotherapy inhibits basophil histamine release, but the assay is cumbersome, and no one has studied the effects of immunotherapy withdrawal.
Intracellular fluorochrome-labeled diamine oxidase (DAO) was used as a novel functional readout of basophil histamine release after immunotherapy. Results were compared with conventional basophil surface expression of activation markers.
Subcutaneous immunotherapy (SCIT)-treated patients (n = 14), sublingual immunotherapy (SLIT)-treated patients (n = 12), participants who completed 3 years of treatment with grass pollen sublingual immunotherapy (the SLIT-TOL group; n = 6), patients with untreated seasonal allergic rhinitis (SAR; n = 24), and nonatopic control subjects (n = 12) were studied. Intracellularly labeled DAO(+) and surface expression of CD203c(bright), CD63(+), and CD107a(+) on chemoattractant receptor-homologous molecule expressed on TH2 lymphocytes (CRTh2)-positive basophils were measured by means of flow cytometry. Serum IgG4 levels and serum inhibitory activity for IgE-allergen complex binding to B cells (IgE-FAB) and basophil histamine release were also determined.
Proportions of allergen-stimulated DAO(+)CRTh2(+) basophils were higher in participants in the SCIT, SLIT, and SLIT-TOL groups (all P < .0001) compared with those in patients in the SAR group. Similarly, there were lower proportions of CRTh2(+) basophils expressing surface CD203c(bright) (all P < .001), CD63 (all P < .001), and CD107a (all P < .01). Rhinitis symptoms were lower in the SCIT, SLIT, and SLIT-TOL groups (P < .001) compared with those in the SAR group. Serum inhibitory activity for IgE-FAB and basophil histamine release were also significantly greater in all immunotherapy groups (P < .05) compared with the SAR group.
These results support long-term clinical and immunologic tolerance during and after grass pollen immunotherapy. Intracellularly labeled DAO expression by basophils merits further investigation as a surrogate biomarker for monitoring efficacy and tolerance after immunotherapy.
免疫疗法抑制嗜碱性粒细胞释放组胺，但该检测方法繁琐，且尚未有人研究免疫疗法停止后的影响。
使用细胞内荧光标记的二胺氧化酶（DAO）作为一种新型的嗜碱性粒细胞组胺释放功能读出方法。结果与传统的嗜碱性粒细胞表面激活标志物表达进行了比较。
对接受皮下免疫治疗（SCIT）的患者（n=14）、舌下免疫治疗（SLIT）的患者（n=12）、完成 3 年花粉舌下免疫治疗（SLIT-TOL 组；n=6）、未经治疗的季节性过敏性鼻炎（SAR）患者（n=24）和非过敏对照受试者（n=12）进行了研究。通过流式细胞术测量趋化因子受体同源物表达于 TH2 淋巴细胞（CRTh2）阳性嗜碱性粒细胞内标记的 DAO（+）和表面表达 CD203c（bright）、CD63（+）和 CD107a（+）。还测定了血清 IgG4 水平和血清抑制 IgE-变应原复合物结合至 B 细胞（IgE-FAB）和嗜碱性粒细胞释放组胺的活性。
在 SCIT、SLIT 和 SLIT-TOL 组的参与者中，与 SAR 组相比，过敏原刺激的 DAO（+）CRTh2（+）嗜碱性粒细胞的比例更高（均 P<.0001）。同样，CRTh2（+）表达表面 CD203c（bright）（均 P<.001）、CD63（均 P<.001）和 CD107a（均 P<.01）的嗜碱性粒细胞比例较低。与 SAR 组相比，SCIT、SLIT 和 SLIT-TOL 组的鼻炎症状更低（P<.001）。与 SAR 组相比，所有免疫治疗组的 IgE-FAB 抑制活性和嗜碱性粒细胞释放组胺也显著更高（P<.05）。
这些结果支持花粉免疫治疗期间和之后的长期临床和免疫耐受。嗜碱性粒细胞内标记的 DAO 表达值得进一步研究，作为免疫治疗后监测疗效和耐受的替代生物标志物。
