Vallier P, Balland S, Harf R, Valenta R, Deviller P
Faculté de Médecine Alexis Carrel, Lyon, France.
Clin Exp Allergy. 1995 Apr;25(4):332-9. doi: 10.1111/j.1365-2222.1995.tb01051.x.
Considering the high occurrence of profilin as an allergen in many plant species, the assumption was made that profilin might be an allergen in Hevea brasiliensis, a member of the latex producing Euphorbiaceae family. Using IgE-binding inhibition by purified profilins we demonstrated that profilin is an IgE-binding component in the cytosolic fraction of natural latex and, to a lower extent, in the rubber fraction. Thirty-five out of 36 sera containing IgE to ragweed-profilin reacted with profilin from latex, indicating structural homologies between profilins from latex and ragweed. A large percentage (59%) of these sera were found to be positive in CAP latex assay. The preincubation of these sera with purified ragweed profilin greatly inhibited the CAP latex. Because profilin is also present in banana extract, it is likely to be involved in cross-sensitivity to banana and latex. In a group of 19 individuals allergic to latex only two had anti-profilin IgE antibodies. Profilin was barely detectable on glove extract immunoblots, whereas some sera from patients allergic to latex reacted with a 15 kDa allergen which was not profilin. Consequently, IgE antibodies to latex-profilin is a questionable factor for sensitization of occupationally-exposed patients; however, sensitization to profilin should be taken into account when interpreting the results of latex IgE antibody assays.
鉴于肌动蛋白在许多植物物种中作为过敏原的高发生率，人们推测肌动蛋白可能是巴西橡胶树（一种产乳胶的大戟科植物）中的过敏原。通过纯化的肌动蛋白抑制IgE结合，我们证明肌动蛋白是天然乳胶胞质部分中的一种IgE结合成分，在橡胶部分中的含量较低。36份含有针对豚草肌动蛋白IgE的血清中有35份与乳胶中的肌动蛋白发生反应，表明乳胶和豚草中的肌动蛋白之间存在结构同源性。发现这些血清中有很大比例（59%）在CAP乳胶检测中呈阳性。用纯化的豚草肌动蛋白对这些血清进行预孵育可大大抑制CAP乳胶检测结果。由于香蕉提取物中也存在肌动蛋白，因此它可能与对香蕉和乳胶的交叉敏感性有关。在一组19名对乳胶过敏的个体中，只有两人具有抗肌动蛋白IgE抗体。在手套提取物免疫印迹上几乎检测不到肌动蛋白，而一些对乳胶过敏患者的血清与一种15 kDa的过敏原发生反应，该过敏原不是肌动蛋白。因此，针对乳胶肌动蛋白的IgE抗体对于职业暴露患者的致敏作用是一个有疑问的因素；然而，在解释乳胶IgE抗体检测结果时应考虑对肌动蛋白的致敏情况。
