Department of Oral Medicine School of Stomatology, Shandong University, Jinan, China.
J Oral Pathol Med. 2010 Feb;39(2):182-7. doi: 10.1111/j.1600-0714.2009.00811.x. Epub 2009 Jul 27.
Candida albicans is the important opportunistic fungal pathogens which can cause oral Candidiasis and even more seriously systemic infection. Apoptosis of C. albicans induced by environmental factor such as weak acid and antifungal drugs were studied recently. Illustrating the phenomenon of apoptosis in C. albicans may help us to discover new antifungal therapy by activating the fungal cells to suicide.
Two oral C. albians clinical isolates which isolated respectively from healthy host [Strain 23C: minimal inhibition concentration (MIC) is 0.125 microg/ml for Amphotericin B (AmB)] and advanced cancer patient (Strain 28A: MIC is 2 microg/ml for AmB), were induced by 1 microg/ml AmB in vitro for 200 min, and then studied the apoptosis markers using terminal deoxynucletidyltransferase-mediated dUTP nick end labeling (TUNEL) (shown by diaminobenzidine and fluorescent isothiocyanate), and the ultrastructure of cell nuclear using transmission electron microscope (TEM), quantitative analysis using flow cytometry for the rapid exposure of phosphatidylserine at the outer membrane and propodium iodide (PI) double staining. C. albicans conference strain YEM30 was used as the control strain.
With TUNEL assay and TEM, we detected the typical characteristics of apoptosis. Strain 23C (with low MIC) showed significantly higher percentage of apoptosis (19.92%) compared with Strain 28A (with high MIC) which was isolated from the cancer patient (7.29%) (P < 0.01). In addition, 7.3% of early apoptosis cells of Strain 23C can form colonies on the plates, while 15% for Strain 28A. None of the PI+ cells can form colony.
Apoptosis of oral C. albicans isolates can be induced by AmB. The feature of antifungal drug susceptibility of the oral C. albicans clinical isolates may associate with the response of apoptosis inducing.
白色念珠菌是一种重要的机会性真菌病原体，可引起口腔念珠菌病，甚至更严重的全身感染。最近研究了环境因素（如弱酸和抗真菌药物）诱导白色念珠菌凋亡的现象。阐明白色念珠菌凋亡的现象可能有助于通过激活真菌细胞自杀来发现新的抗真菌疗法。
从健康宿主中分离的 2 株口腔白色念珠菌临床分离株[最小抑菌浓度（MIC）为 0.125 μg/ml 的两性霉素 B（AmB）（菌株 23C）]和晚期癌症患者（MIC 为 2 μg/ml 的 AmB（菌株 28A）]，体外用 1 μg/ml 的 AmB 诱导 200 分钟，然后使用末端脱氧核苷酸转移酶介导的 dUTP 缺口末端标记（TUNEL）（通过二氨基联苯胺和荧光异硫氰酸酯显示）和透射电子显微镜（TEM）观察细胞核的超微结构，使用流式细胞术进行快速检测外膜磷脂酰丝氨酸暴露和碘化丙啶（PI）双重染色，对细胞进行定量分析。白色念珠菌标准菌株 YEM30 用作对照菌株。
通过 TUNEL 检测和 TEM，我们检测到了典型的凋亡特征。MIC 较低的菌株 23C（23C）（19.92%）与分离自癌症患者的 MIC 较高的菌株 28A（7.29%）相比，凋亡率明显更高（P<0.01）。此外，23C 株的 7.3%早期凋亡细胞可以在平板上形成菌落，而 28A 株为 15%。没有 PI+细胞可以形成菌落。
AmB 可诱导口腔白色念珠菌分离株凋亡。口腔白色念珠菌临床分离株的抗真菌药物敏感性特征可能与凋亡诱导反应有关。
