查了文献说是SYTO® 9和PI是live/dead凋亡试剂的一种,自己理解的是他之所以不同于Annexin V-FITC/PI双染细胞凋亡检测试剂盒是因为SYTO® 9和PI两者都是核酸染料,不但可以染色细菌等原核生物,而且可以染色藻类等有细胞壁的真核生物,多数SYTO® 9和PI染色都是荧光显微镜或者激光共聚焦下直观看出绿色荧光为活的,不知道能不能上流式细胞仪检测?Annexin V-FITC/PI双染细胞凋亡检测试剂是检测细胞膜完整的细胞早期凋亡的试剂这个可以上流式细胞仪我知道,但是Annexin V-FITC/PI双染不能染色带有细胞壁的藻类细胞,但是我又看到有用染料 SYTOX-Green或者SYBRgreenⅠ( SYBR)方法直接染色有细胞壁的藻类,怎么解释呢?是两种染料能直接通过细胞壁而检测细胞膜的通透性来检测细胞的死亡情况吗?那么这样一来不就有无细胞壁无所谓了吗?就不用除去细胞壁了吗?
文章:Flow cytometric analysis of phytoplankton viability following viral infection
摘要:
Two flow cytometric assays using physiological probes were used on the phytoplankton species Phaeocystis pouchetii and Micromonas pusilla to examine the assays' utility in detecting viral infections. Dead cells were detected using the membrane impermeant nucleic-acid dye SYTOX-Green, which stains algal cells that have lost their membrane integrity. Live cells were detected using the membrane permeant dye Calcein-AM, which is hydrolyzed by intracellular esterases into a green fluorescent charged form. We found that both assays are easy to use, are reproducible and can indeed be used as markers of the viability of individual phytoplankton cells following infection by viruses. Cell death rates up to 0.8 d
AnnexinⅤ是一种分子量为35-36kD的Ca依赖性磷脂结合蛋白,属于生物大分子。SYTO® 9、SYTOX-Green或者SYBR green Ⅰ都是小分子。它们通过细胞壁的能力是不同的。另外,AnnexinⅤ是与细胞膜外表面的PS结合的,细胞壁与细胞膜一般是紧密贴合的(除非质壁分离),可能会阻碍两者的结合,所以需要去除细胞壁。SYTO® 9、SYTOX-Green或者SYBR green Ⅰ都是要进入细胞内部和细胞内的核酸结合的,所以只要能通过细胞壁和细胞膜即可,细胞壁存不存在对染色结果无影响。