Diamond R D, Krzesicki R, Jao W
J Clin Invest. 1978 Feb;61(2):349-59. doi: 10.1172/JCI108945.
Large forms of Candida are characteristically present in invasive lesions and are often cleared by host defenses. Therefore, an in vitro system was developed to study interactions between leukocytes and pseudohyphae. By light, phase contrast, and electron microscopic observations, in the absence of serum, neutrophils attached to and spread over the surfaces of partially ingested pseudohyphae, which then appeared damaged. Using a new assay which measured neutrophil-induced inhibition of uptake of [(14)C]cytosine by Candida, damage to Candida in the absence of serum was 53.04+/-2.96% by neutrophils from 27 normal subjects. With serum, damage to Candida increased because of opsonization by low levels of anti-Candida immunoglobulin G in normal sera. Damage to Candida was inhibited by colchicine, cytochalasin B, and 2-deoxyglucose, which interfered with spreading of neutrophils over the surfaces of Candida. Dibutyryl cyclic AMP, theophylline, and isoproterenol also inhibited damage to Candida. Hydrocortisone was inhibitory in levels (10 muM) achievable with pharmacologic doses in man. Light, fluorescence, and electron microscopy indicated that neutrophils degranulated after contact with Candida. Quantitative studies revealed only a minimal increase in specific release of lysosomal enzymes from azurophil granules, but much greater release of lysozyme from specific granules. Candida activated neutrophil oxidative microbicidal mechanisms, as shown by iodination of Candida by neutrophils, and chemiluminescence from neutrophils interacting with Candida. Unlike live Candida, killed Candida did not induce chemiluminescence, were not iodinated, and did not attach to neutrophils by microscopy. Like Candida pseudohyphae, contact between neutrophils and hyphal forms of Aspergillus and Rhizopus occurred in the absence of serum. This did not occur with Cryptococcus neoformans, an encapsulated yeast, and was low with Candida yeasts. These findings indicate that neutrophils can recognize and attach to Candida pseudohyphae, then damage the Candida. This may represent a general reaction between neutrophils and large forms of fungi. Though the size of the organisms precludes complete ingestion, neutrophil oxidative microbicidal mechanisms are activated, and preferential release of contents of specific granules appears to occur.
侵袭性病变中通常存在大型念珠菌，且往往会被宿主防御机制清除。因此，开发了一种体外系统来研究白细胞与假菌丝之间的相互作用。通过光学显微镜、相差显微镜和电子显微镜观察发现，在无血清的情况下，中性粒细胞附着在部分被吞噬的假菌丝表面并在其表面铺展，随后假菌丝出现损伤。使用一种新的检测方法来测量中性粒细胞诱导的念珠菌对[（14）C]胞嘧啶摄取的抑制作用，来自27名正常受试者的中性粒细胞在无血清情况下对念珠菌的损伤率为53.04±2.96%。有血清时，由于正常血清中低水平的抗念珠菌免疫球蛋白G的调理作用，对念珠菌的损伤增加。秋水仙碱、细胞松弛素B和2-脱氧葡萄糖可抑制对念珠菌的损伤，它们会干扰中性粒细胞在念珠菌表面的铺展。二丁酰环磷腺苷、茶碱和异丙肾上腺素也能抑制对念珠菌的损伤。氢化可的松在人体药理学剂量可达到的水平（10μM）时具有抑制作用。光学显微镜、荧光显微镜和电子显微镜观察表明，中性粒细胞与念珠菌接触后会脱颗粒。定量研究显示，嗜天青颗粒中溶酶体酶的特异性释放仅略有增加，但特异性颗粒中溶菌酶的释放则显著增加。念珠菌激活了中性粒细胞的氧化杀菌机制，如中性粒细胞对念珠菌碘化以及中性粒细胞与念珠菌相互作用产生化学发光所示。与活念珠菌不同，死念珠菌不会诱导化学发光，不会被碘化，显微镜下也不会附着在中性粒细胞上。与念珠菌假菌丝一样，在无血清情况下中性粒细胞与曲霉菌和根霉菌的菌丝形式之间也会发生接触。而对于新型隐球菌（一种有荚膜的酵母）则不会发生这种情况，对念珠菌酵母的接触率较低。这些发现表明，中性粒细胞能够识别并附着在念珠菌假菌丝上，然后损伤念珠菌。这可能代表了中性粒细胞与大型真菌之间的一种普遍反应。尽管真菌的大小使其无法被完全吞噬，但中性粒细胞的氧化杀菌机制被激活，且特异性颗粒内容物似乎会优先释放。
