Mark P G, Segal D B, Dallaire M L, Garman R D
ImmuLogic Pharmaceutical Corporation, Waltham, Massachusetts 02154, USA.
Clin Exp Allergy. 1996 Nov;26(11):1316-28.
In allergic individuals exposure to allergen leads to the induction of allergen-specific IgE which, upon binding to its high affinity receptors on mast cells and basophils, primes these cells for degranulation. This degranulation, a result of specific IgE/allergen-interaction, initiates the debilitating symptoms of allergy and the potentially life-threatening symptoms of anaphylaxis. The lack of symptoms following antigen encounter by non-allergic individuals is probably due to the undetectable levels of allergen-specific IgE in the plasma of non-allergic individuals.
To compare the immune responses of allergic and non-allergic individuals.
We compared the immune responses of 42 cat-allergic subjects with 16 non-cat-allergic subjects to the major cat allergen, Fel d 1. We have measured plasma immunoglobulin levels and the proliferative responses of fel d 1 primed T cell lines to Fel d 1 peptides.
While these two groups have similar levels of Fel d 1 specific IgG, only subjects in the cat-allergic group have detectable Fel d 1 specific IgE. Affinity purified Fel d 1 was used to generate T cell lines from peripheral blood mononuclear cells of these same subjects. The proliferative responses of these T cell lines to intact Fel d 1 and a set of overlapping peptides covering the entire sequence of the molecule demonstrated that the pattern of epitope recognition was similar in both groups.
Our data suggest that factors other than T cell recognition of specific epitopes are responsible for the nature of allergic immune responses generated when allergen is encountered.
在过敏个体中，接触过敏原会导致诱导产生过敏原特异性IgE，该IgE与肥大细胞和嗜碱性粒细胞上的高亲和力受体结合后，使这些细胞做好脱颗粒的准备。这种脱颗粒是特异性IgE/过敏原相互作用的结果，引发了使人虚弱的过敏症状以及可能危及生命的过敏反应症状。非过敏个体接触抗原后没有症状，可能是由于非过敏个体血浆中过敏原特异性IgE水平检测不到。
比较过敏个体和非过敏个体的免疫反应。
我们比较了42名对猫过敏的受试者和16名对猫不过敏的受试者对主要猫过敏原Fel d 1的免疫反应。我们测量了血浆免疫球蛋白水平以及经Fel d 1致敏的T细胞系对Fel d 1肽的增殖反应。
虽然这两组的Fel d 1特异性IgG水平相似，但只有猫过敏组的受试者能检测到Fel d 1特异性IgE。用亲和纯化的Fel d 1从这些受试者的外周血单核细胞中生成T细胞系。这些T细胞系对完整的Fel d 1和一组覆盖该分子整个序列的重叠肽的增殖反应表明，两组的表位识别模式相似。
我们的数据表明，当接触过敏原时，除了T细胞对特定表位的识别外，其他因素也导致了所产生的过敏免疫反应的性质。
