Stein D K, Malawista S E, Van Blaricom G, Wysong D, Diamond R D
Evans Memorial Department of Clinical Research, Boston University Medical Center Hospital, Massachusetts, USA.
J Infect Dis. 1995 Aug;172(2):511-20. doi: 10.1093/infdis/172.2.511.
Killing of Candida albicans hyphae requires oxidant generation by neutrophils (PMNL), but it is uncertain whether hyphal killing is mediated by PMNL oxidants alone or requires contributions by granule constituents. This was assessed using U-cytoplasts (U-CYT), anucleate PMNL fragments depleted of cytoplasmic granules but retaining motility and respiratory burst activity. Granule-depleted U-CYT killed Staphylococcus aureus, but hyphae remained viable despite targeted generation of putatively fungicidal oxidants by avidly adherent U-CYT. Hyphal killing occurred by combining U-CYT with sublethal concentrations of purified PMNL granule extracts approximating those present in equivalent numbers of intact PMNL. Contributions of granule constituents were not entirely attributable to purified granule constituents with known antimicrobial activity (lactoferrin, cathepsin G, myeloperoxidase, and human neutrophil peptide defensins 1-3) individually or combined. Thus, oxidant generation by intact PMNL may be necessary but not always sufficient to mediate hyphal killing without complementary nonoxidative mechanisms.
杀灭白色念珠菌菌丝需要中性粒细胞（PMNL）产生氧化剂，但菌丝的杀灭是仅由PMNL氧化剂介导，还是需要颗粒成分的参与尚不确定。这是通过使用U-胞质体（U-CYT）进行评估的，U-胞质体是无核的PMNL片段，缺乏细胞质颗粒，但保留运动性和呼吸爆发活性。缺乏颗粒的U-CYT可杀死金黄色葡萄球菌，但尽管紧密黏附的U-CYT有针对性地产生了假定的杀真菌氧化剂，菌丝仍保持存活。将U-CYT与亚致死浓度的纯化PMNL颗粒提取物（其浓度近似于等量完整PMNL中所含的浓度）相结合可实现对菌丝的杀灭。颗粒成分的作用并不完全归因于具有已知抗菌活性的纯化颗粒成分（乳铁蛋白、组织蛋白酶G、髓过氧化物酶和人中性粒细胞肽防御素1-3）单独或联合作用。因此，完整PMNL产生氧化剂可能是介导菌丝杀灭所必需的，但若无互补的非氧化机制，往往并不足以实现菌丝的杀灭。
