Université de Toulouse-3, LPSNPR (Laboratoire Pharmacochimie des Substances Naturelles et Pharmacophores Redox), Toulouse, France.
Malar J. 2010 Feb 11;9:49. doi: 10.1186/1475-2875-9-49.
The activity of promising anti-malarial drugs against Plasmodium gametocytes is hard to evaluate even in vitro. This is because visual examination of stained smears, which is commonly used, is not totally convenient. In the current study, flow cytometry has been used to study the effect of established anti-malarial drugs against sexual stages obtained from W2 strain of Plasmodium falciparum. Gametocytes were treated for 48 h with different drug concentrations and the gametocytaemia was then determined by flow cytometry and compared with visual estimation by microscopy.
Initially gametocytaemia was evaluated either using light microscopy or flow cytometry. A direct correlation (r2 = 0.9986) was obtained. Two distinct peaks were observed on cytometry histograms and were attributed to gametocyte populations. The activities of established anti-malarial compounds were then measured by flow cytometry and the results were equivalent to those obtained using light microscopy. Primaquine and artemisinin had IC50 of 17.6 microM and 1.0 microM, respectively. Gametocyte sex was apparently distinguishable by flow cytometry as evaluated after induction of exflagellation by xanthurenic acid. These data form the basis of further studies for developing new methods in drug discovery to decrease malaria transmission.
即使在体外,有前景的抗疟药物对疟原虫配子体的活性也难以评估。这是因为常用的染色涂片目视检查并不完全方便。在本研究中,使用流式细胞术研究了从恶性疟原虫 W2 株获得的性阶段对已建立的抗疟药物的作用。用不同药物浓度处理配子体 48 小时,然后通过流式细胞术和显微镜目视估计来确定配子体血症,并进行比较。
最初使用显微镜或流式细胞术评估配子体血症。直接获得了相关性(r2 = 0.9986)。在细胞仪的直方图上观察到两个明显的峰,归因于配子体群体。然后通过流式细胞术测量已建立的抗疟化合物的活性,结果与使用显微镜观察获得的结果相当。伯氨喹和青蒿素的 IC50 分别为 17.6μM 和 1.0μM。黄嘌呤酸诱导出芽后,通过流式细胞术显然可以区分配子体的性别。这些数据为开发新的药物发现方法以减少疟疾传播的进一步研究奠定了基础。