CellTrace™ Calcein Red-Orange, AM - Special Packaging - FAQs

View additional product information for CellTrace™ Calcein Red-Orange, AM - Special Packaging - FAQs (C34851)

16 product FAQs found

我染色两个细胞类群,一种是用CellTracker Green染料,另一种是用CellTracker Red染料,但它看起来像是红色染料的与绿色细胞之间出现了交叉。这是怎么回事?

一种可能性是染料之间的光谱渗漏。务必通过在绿光下成像红色细胞,在红光下成像绿色细胞的方式检查单色样品,对其他颜色使用最佳成像设置。如果您在对照中看到这些渗漏,那么就需要减少染料标记浓度以降低染料的亮度,或者选择那些光谱相距较远的染料。如果不是渗漏的问题,另一种可能性是细胞在染色后没有充分清洗,使得一些未结合的染料残留下来,这些染料进入后会标记其他细胞。延长清洗次数和时间应该会有帮助。

当我用钙黄绿素 AM对细胞进行染色时,细胞经过固定处理后信号就消失了,为什么?

Calcein AM扩散到细胞中,“AM”部分由细胞酯酶裂解,随后染料分子的荧光信号可以在细胞质中被观测到,但其不结合到细胞组分。这意味着它们能够为“整个细胞”染色。这也意味着染料不能通过醛类固定剂进行交联,因此染料会在固定时丢失。此外,质膜的任何干扰(例如去垢剂或胰蛋白酶处理)都会导致染料从细胞中渗漏。

我试着用CellTracker dyes或CFDA SE对我的细胞进行染色,但是没有观察到很多信号,我该怎么做?

首先,确定您是在无血清条件下进行染色的。因为血清具有酯酶活性,会过早的裂解这些染料上的AM基团,进而阻止其进入细胞。染色之后即可将细胞移回含血清培养基中。除此之外,您可以尝试增加浓度和标记时间以获得更高的强度的信号。

我想用钙黄绿素染料标记整个细胞。我可以借此跟踪我的细胞多久,我可以固定它们吗?

钙黄绿素染料扩散到细胞中,“AM”部分由细胞酯酶切割,随后可以在细胞质中观察到而未结合任何胞内成分。这意味着它们标记了“整个细胞”。但是这也意味着它们可以通过正常细胞的外排机制被泵出。有时这一过程时间很短,尤其是显示出抗药性类型的细胞,除非外排被抑制(如使用丙磺舒抑制外排)。这也意味着染料不能被醛类固定剂所交联(不同于蛋白质结合CellTracker染料),因此染料会在固定时丢失。此外,质膜的任何干扰(例如去垢剂或胰蛋白酶处理)都会导致染料从细胞中渗漏。

我试图采用CellTrace 染色剂来检测细胞增殖情况,但未看到各次细胞分裂的分离峰。我该如何优化这一实验?

用CellTrace试剂绘制出好的传代曲线的关键是在开始时均匀标记细胞,使它们在标记零点有紧密的变异系数(CV)。如果峰太宽,迭代相互重叠,一系列峰将成为一个驼峰。由于染色程度与细胞大小成正比,可以从统一的细胞群(而非淋巴细胞和粒细胞等混合的细胞群)开始标记,实现均匀的标记。细胞标记时间很短,所以您需要预先稀释染料,迅速混入你的细胞。请确保您的细胞未沉积在试管底部。实现这一点最简单的方法就是准备一份2X染色液(1×= 1-10μM),在一半体积(无血清或BSA)培养基中重悬细胞。将染料添加到细胞中并倒置几次以混合。染色过程中轻轻晃动细胞。染料孵育结束后(20分钟,37℃)即添加血清或BSA(至少1%),以清除任何残留的未反应染料。离心细胞,洗涤一遍,然后在完全培养基中重悬。经10-20分钟的脱酯化孵育后,细胞即可用于你们的实验。一定要确保有一个零点对照,因为您需要知道细胞第一次传代的时间。

流式细胞术的优势有哪些?

•可测定来自单个细胞的数据。
•可从大量细胞中获得数据,产生细胞群的丰富统计学分析结果。
•由于可测定单个细胞,能够揭示种群的异质性。
•支持多重检测,可鉴定小型亚群。
•可以快速分析数以千计的细胞。
•非常适合血液样本和其他悬浮细胞。
•数据获取后,可以多次重复分析。
•流式细胞仪文件(FCS)可以归档。

我能在流式细胞仪上进行哪些应用?

可进行多种应用,包括免疫分型、细胞周期分析、凋亡检测(如膜联蛋白V染色检测实验)、CellEvent Caspase-3/7检测、TUNEL检测、细胞活性检测、增殖检测(如CellTrace 检测和Click-iT EdU检测)、MitoProbe检测法测定线粒体电势、利用计数微球进行细胞计数。

I need a general cytoplasmic stain that does not overlap with the GFP in my cells. What do you recommend?

Calcein AM, a green dye, is typically used as a general cytoplasmic stain, but not recommended with GFP-positive cells. For GFP-expressing cells there are other colors available: Calcein Blue AM, Calcein Violet AM, and Calcein Red-Orange AM. The retention time of these dyes in live cells is dependent upon the inherent properties of the cell.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

How do I reconstitute CellTrace Calcein Red-Orange, AM (Cat. No. C34851)?

You can dissolve the dye using high-quality, anhydrous dimethylsulfoxide (DMSO) up to 1 -2 mg/mL. The acetoxymethyl ester (AM) moiety on CellTrace Calcein Red-Orange, AM is susceptible to hydrolysis when exposed to water absorbed by the DMSO. Once prepared, use the DMSO stock solutions of CellTrace Calcein Red-Orange, AM within a short time period. Aqueous working solutions containing the dye should be prepared fresh and used on the same day. The working principle of CellTrace Calcein Red-Orange, AM is very similar to Calcein, AM, cell-permeant dye (Cat. No. C1430). The protocol given in the product manual for Calcein, AM with an additional wash step is suitable. Wash cells with pre-warmed buffer (e.g. PBS, HBSS) to remove residual serum present in the culture medium, load cells with reagent in buffer, incubate from 15-45 minutes and then wash cells with medium (with or without serum). For further information please see the User Guide.

Find additional tips, troubleshooting help, and resources within our Cell Imaging Support Center.

I stained two populations of cells, one with CellTracker Green and the other with CellTracker Red, but it looks like there may be crossover of the red dye to the green cells. What is going on?

One possibility is that there is spectral bleedthrough between the dyes. Be sure to check the single-color samples by imaging the red cells in green and imaging the green cells in red, using the optimal imaging settings for the other color. If you see bleedthrough with these controls, then you will have to reduce the dye label concentration to reduce the brightness of the dyes, or choose dyes that are farther apart spectrally. If the issue isn’t bleedthrough, another possibility is that the cells were not adequately washed after staining, allowing some unincorporated dye to remain and label the other cells after they were introduced. Extending washes and wash times should help with this.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

I stained my cells with Calcein, AM, but the signal went away after I fixed my cells. Why is this?

Calcein, AM diffuses into cells, the 'AM' moiety is cleaved by cellular esterases, and then the dye molecules are observed in the cytoplasm without binding to anything. This gives a 'whole cell' stain. It also means that the dyes are not crosslinked with aldehyde-based fixation and thus will be lost upon fixation. Additionally, any disruption of plasma membrane, such as with detergents or trypsinization, will lead to leakage of the dye from the cell.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

I'm trying to stain my cells with CellTracker dyes or CFDA SE, but I'm not seeing much signal. What can I do?

First, make sure you aren’t staining in the presence of serum, since serum can have esterase activity that can prematurely cleave the AM group on these dyes, preventing entry into cells. After staining, it’s okay to return the cells to medium containing serum. After this, you can try increasing the concentration and label time to get a higher intensity.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

I like how calcein dyes label the whole cell. How long can I track my cells with them, and can I fix them?

Calcein dyes diffuse into cells, the 'AM' moiety is cleaved by cellular esterases and then are observed in the cytoplasm without binding to anything. This provides a 'whole cell' label. Calcein dyes may be pumped out by normal cellular efflux mechanisms, sometimes within a very short time, especially for cell types that may exhibit drug resistance, unless the efflux is inhibited (such as with probenecid). The dyes are not crosslinked with aldehyde-based fixation, unlike protein-binding CellTracker dyes, and thus will be lost upon fixation. Additionally, any disruption of plasma membrane, such as with detergents or trypsinization, will lead to leakage of the dyes from the cell.

Find additional tips, troubleshooting help, and resources within our Cell Tracing and Tracking Support Center.

I am trying to assay cell proliferation with a CellTrace stain, and I am not seeing separate peaks for each cell division. How can I optimize this assay?

The key to good generational profiles with CellTrace reagents is starting with cells that are evenly labeled so that they have a tight coefficient of variance (CV) when run at time zero after labeling. If the peak is too broad, the generations will overlap each other and the series of peaks will become a hump. Even labeling can be achieved by starting with a uniform cell population (not a mixture of lymphocytes and granulocytes for example) as staining will be proportional to cell size. Cells are labeled rapidly, so you want to pre-dilute the dye and mix it into your cells rapidly. Be sure that the cells are not sitting in a clump in the bottom of your tube. The easiest way to do this is to make a 2x dye solution (1x = 1-10 µM) and resuspend your cells in a half volume of medium (no serum or BSA). Add the dye to the cells and invert a few times to mix. Gently agitate the cells during staining. Once the dye incubation is over (20 min, 37 degrees C), add serum or BSA (at least 1%) to scavenge any remaining unreacted dye. Spin down cells, wash 1x, and resuspend in complete medium. After a 10-20 min incubation to undergo de-esterification, cells are ready to be set up for whatever treatment you are planning. Be sure to keep a time zero control as you need to know where the first generation ran.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

What are the advantages of flow cytometry?

-Measures data from single cells.
-Data are obtained for a large number of cells, generating a rich statistical analysis of cell populations.
-Because single cells are measured, it will reveal heterogeneity within a population.
-With the ability to multiplex, small sub-populations can be identified.
-Thousands of cells can be analyzed rapidly.
-It is ideally suited for blood samples and other cells in suspension.
-Data can be re-analyzed multiple times after acquisition.
-Flow cytometry files (FCS) can be archived.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

What kinds of applications can I run on a flow cytometer?

There are several applications, some of which include immunophenotyping, cell cycle analysis, apoptosis assays such as annexin V staining, CellEvent Caspase-3/7 assay, and TUNEL assay, cell viability, proliferation assays such as CellTrace assay and Click-iT EdU assay, measurements of mitochondrial potential with MitoProbe assays, and cell counting using counting beads.

Find additional tips, troubleshooting help, and resources within our Flow Cytometry Support Center.