Nexcelom Bioscience has launched a new application for hepatocytes for its Cellometer Vision automated cell counter that provides an automated counting method for a type of cell for which no good counting method currently exists, said Craig Weiss, vice president of marketing for Nexcelom.
The application was launched during a session at the Society for Toxicology's annual meeting, held this week in Baltimore.
Hepatocytes do not have the round morphology typical of other cell types. They are oddly shaped, and living and dead hepatocytes often appear very similar when stained with trypan blue.
In addition, they have a tendency to cluster together. Manually counting them is thus challenging, and user-to-user variability and the interpretation of results are issues.
Traditional automated systems such as flow cytometers, because of the clumpy and delicate nature of hepatocytes, would either destroy the hepatocytes or become clogged because the cells would clump together.
"What our system does is, for the first time, provide a very simple, automated way to analyze and determine the viability of primary hepatocytes," Weiss told CBA News.
He said the Cellometer Vision counts hepatocytes by dually staining them with acridine orange and propidium iodide. Acridine orange will stain the live cells and PI will stain the dead cells, and by analyzing the fluorescent image, "you can count and compare the live cells to the dead cells," said Weiss.
The modifications to the Cellometer Vision for this new application were primarily software based. "We modified the software so that it could adequately decluster and recognize the individual cells," Weiss said.
The software was also improved so that "we can overlay the fluorescence images of live cells over that of dead cells, so that you can view on the same screen what is live and what is dead, even though they are coming from two different fluorescence channels," he said. This ability to simultaneously view live and dead cells helps with the observation of the morphology.
Weiss said that the newly modified software comes standard with the machine.
Nexcelom will be launching the application in the US at first, but in the next few weeks "we will be launching this globally," Weiss said.
On My Count
The T4 and M10 are Nexcelom's basic cell counters, which were designed to automate and simplify manual counting on a hemocytometer, said Weiss. Other players in the market include the Countess from Life Technologies, Beckman Coulter's Vi-Cell, and Cedex from Roche.
Weiss said that the M10 has a slightly higher magnification than the T4 "if you are looking at really small cells, like yeast platelets and algae."
The Cellometer Vision has the same capabilities as the T4 and M10, but it also has the ability to capture a fluorescence image of that same cell sample. "You can determine the ratio of cells fluorescing positively to cells fluorescing negatively, and determine the distribution of the fluorescence intensity," Weiss said.
A population of cells can be further characterized based on their fluorescence properties.
One of the applications for which the Cellometer Vision is used include determining GFP transfection rates. In addition, any type of DNA staining "such as PI viability or calcium AM is now very easily automated," said Weiss. The Cellometer Vision shares market space with the Cellavista from Roche and Guava's EasyCyte and PCA-96 platforms.
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Users of the Cellometer Vision would be researchers whose work focuses on toxicology and ADME/tox, and those who are studying hepatocytes and the effect of compounds on hepatocytes.
"We will, from a traditional marketing standpoint, take a targeted approach to marketing this new application," such as finding out who the researchers are who are doing toxicology research, working with companies who supply hepatocytes, and giving talks, Weiss said.
In terms of future applications for the Cellometer Vision, he did not elaborate, except to say that, "Our goal is to have as many fluorescence-based cellular applications as possible available for the machine." Weiss also said that the "world's leading pharma companies" were early adopters of the hepatocyte application.