Spry C J, Tai P C, Davies J
Postgrad Med J. 1983 Mar;59(689):147-53. doi: 10.1136/pgmj.59.689.147.
Although an association between high blood eosinophil counts and endomyocardial disease has been known for nearly a hundred years, the reasons for this were not understood. Brockington, Luzzatto and Osunkoya (1970) suggested that eosinophil leucocytes, in susceptible persons, by some unknown mechanisms, cause endomyocardial damage. Evidence to support this possibility has come from three sources: (1) Clinical studies have shown that very high blood eosinophil counts, from any cause, can be associated with endomyocardial disease, and in some patients it has been possible to show that eosinophilia preceded the onset of heart disease. (2) The development of heart disease has been associated with the presence of degranulated eosinophils in the blood and tissues, including damaged endomyocardium, and raised serum levels of eosinophil granule basic proteins have been found in many of these patients. (3) Low concentrations of eosinophil secretion products (which contain these eosinophil granule basic proteins) have been found to injure isolated heart cells in vitro. Studies with purified eosinophil granule basic proteins have shown that cardiac cell damage is the result of a specific toxic effect of eosinophil cationic protein on the plasma membrane and two enzyme complexes (pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase) involved in mitochondrial respiration. These results support the suggestion that under certain conditions, eosinophils may damage the heart, leading to endomyocardial disease, and they offer new approaches for the early diagnosis and treatment of endomyocardial disease both in temperate and tropical countries.
尽管血液中嗜酸性粒细胞计数升高与心内膜疾病之间的关联已为人所知近百年，但其中的原因仍不清楚。布罗金顿、卢扎托和奥孙科亚（1970年）提出，在易感人群中，嗜酸性粒细胞通过某些未知机制导致心内膜损伤。支持这一可能性的证据来自三个方面：（1）临床研究表明，任何原因导致的血液中嗜酸性粒细胞计数极高都可能与心内膜疾病有关，而且在一些患者中已证实嗜酸性粒细胞增多先于心脏病发作。（2）心脏病的发展与血液和组织（包括受损的心内膜）中脱颗粒的嗜酸性粒细胞的存在有关，并且在许多此类患者中发现血清嗜酸性粒细胞颗粒碱性蛋白水平升高。（3）已发现低浓度的嗜酸性粒细胞分泌产物（其中含有这些嗜酸性粒细胞颗粒碱性蛋白）在体外会损伤分离的心脏细胞。对纯化的嗜酸性粒细胞颗粒碱性蛋白的研究表明，心脏细胞损伤是嗜酸性粒细胞阳离子蛋白对质膜以及参与线粒体呼吸的两种酶复合物（丙酮酸脱氢酶和2-氧代戊二酸脱氢酶）产生特定毒性作用的结果。这些结果支持了在某些情况下嗜酸性粒细胞可能损害心脏导致心内膜疾病的观点，并且为温带和热带国家心内膜疾病的早期诊断和治疗提供了新方法。
