Gupta N, Sriramarao P, Kori R, Rao P V
Department of Biochemistry, Indian Institute of Science, Bangalore.
Int Arch Allergy Immunol. 1995 Aug;107(4):557-65. doi: 10.1159/000237099.
Allergens from the pollen of Parthenium hysterophorus (American feverfew), responsible for high incidence of allergic rhinitis, were found by immunoprint analysis to be localized on the surface of the pollen grains. The allergens were released very rapidly when extracted in vitro. The allergenic activity of the rapid (10 s) and slowly (20 h) released pollen proteins was comparable by in vivo skin test and ELISA inhibition assay. The isoelectric focusing patterns of the rapid and slowly released proteins were also identical. SDS-PAGE and Western blot analysis revealed that all the major pollen allergens with molecular weight 14, 28, 31, 37 and 45 kDa were eluted within 10 s of extraction. Periodate-Schiff staining showed that the 28, 31 and 45 kDa components of the pollen extract are glycoproteins. The pollen allergens released after different periods of extraction lost 75% of IgE binding activity when subjected to in situ sodium m-periodate oxidation under controlled conditions, while 80% of the allergenic activity was still retained after extensive proteolysis. Our results support the clinical observation of a rapid onset of symptoms of allergic rhinitis in patients sensitive to Parthenium pollen, mediated predominantly by glycoproteins.
通过免疫印迹分析发现，造成过敏性鼻炎高发的银胶菊（美国费菊）花粉中的过敏原定位于花粉粒表面。在体外提取时，这些过敏原释放得非常迅速。通过体内皮肤试验和酶联免疫吸附测定（ELISA）抑制试验可知，快速（10秒）和缓慢（20小时）释放的花粉蛋白的致敏活性相当。快速和缓慢释放的蛋白质的等电聚焦图谱也相同。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）和蛋白质免疫印迹分析显示，所有分子量为14、28、31、37和45 kDa的主要花粉过敏原在提取10秒内就被洗脱出来。过碘酸-希夫染色显示，花粉提取物中28、31和45 kDa的成分是糖蛋白。在可控条件下进行原位间碘酸钠氧化时，不同提取时间后释放的花粉过敏原失去了75%的IgE结合活性，而在广泛的蛋白水解后仍保留80%的致敏活性。我们的研究结果支持了临床上对银胶菊花粉敏感患者过敏性鼻炎症状迅速发作的观察，这主要由糖蛋白介导。
