Cutting Cells

What is cell cutting?

Cell cutting summarizes techniques which enable to extract specific cells by cutting tissue, fixed cells as well as cutting living cells. Typically, target cells are identified using a microscope. Cutting cells, scientists can excise large tissue areas, for example to separate distinct structures in a tissue section. Cutting cells can also refer to single cell cutting to isolate single cells from tissue sections, cell preparations such as cytospins or smears, or to perform live cell cutting to extract single cells from cell culture.

How does cutting cells work?

Cell cutting today mainly refers to a technology termed Laser Microdissection. Before this advanced cutting cells technology had been brought to market in the early 2000s, scientists had often used scalpels to cut specific areas from tissue sections. However, this kind of tissue cutting method is not very precise even when done under a microscope by a skilled person. Laser microdissection in contrast provides a high precision technique for cutting cells. A laser is applied to cut predefined areas such as larger structures but also single cells from various sources. After cutting cells, excised pieces such as larger tissue areas as well as single cell cuts are being transferred into tubes or cell culture dishes to allow for molecular analyses or for further cultivation, respectively.

What different techniques and methods are there for cell cutting? What are the most common or popular techniques for cell cutting?

The method of choice for cutting cells mainly depends on the precision and accuracy required for downstream applications. Cutting cells using a sharp scalpel and manually excising the target cells is applied if large structures need to be separated from non-target structures. Thus, the target structure needs to be large enough to be cut manually and it needs to be easy to distinguish from non-target structures. These cutting cells techniques are suitable for tissue enrichment, but not to obtain a highly pure cell preparation. To isolate smaller target areas as well as single cells, laser microdissection will be the cutting cells method of choice. The laser cuts the selected target cells with high precision and accuracy. Thus, single cell cutting is achieved to isolate single and even rare target cells with minimum contamination from the surrounding tissue. In addition, live cell cutting is enabled without compromising the cells’ integrity and viability. Therefore, after cutting cells, isolated living cells can be subjected to sensitive molecular analyses such as transcriptomics, or they can be used to form a homogenous cell culture from mixed culture conditions. With this highly specific cutting cells technology, laser microdissection in contrast to manual scalpel scraping offers a large spectrum of possible applications in various research areas as well as in the clinics.

How do the products and solutions of MMI help me when it comes to cutting cells?

With the MMI CellCut, MMI offers a unique technology for cutting cells by precise, reliable and flexible laser microdissection. The laser MMI is applying is a low damage laser to neither harm the isolated cells nor the surrounding tissue which might be subjected to comparative analyses. Even live cell cutting can be performed using the MMI CellCut system. After cutting cells, the cells can be subjected either to any molecular analysis or to further cultivation as the cells’ integrity and viability will not be compromised by laser cell cutting. Moreover, the laser is fixed while the high-precision stage is moving during laser cell cutting to provide identical cutting results at any point of the sample and even for large target areas.

Excised target cells will be collected by the patented CapLift technology applying adhesive MMI Isolation Caps. Intriguingly, the sample is being isolated in a contact-free and contamination-free way, as the sample is sandwiched between a glass slide and a membrane slide. The membrane slide is cut together with the sample of interest. Thus, only the excised membrane adheres to the IsolationCap with the sample being attached to the opposite side of the membrane. This so-called “CapSure” technology also ensures that the samples, even tiny pieces of tissue such as single cells, are reliably collected as the IsolationCap can hold the sample in place already during laser tissue cutting thus preventing the excised tissue from being flipped away by electrostatic forces. Especially when cutting rare cells, it is essential to confirm successful cell isolation. The “CapSure” method also allows to easily collect larger tissue areas in a single piece by the adhesive IsolationCaps.

To be able to identify target cells for cutting cells, different stainings such as H&E or IHC can be applied. In addition, the MMI CellCut microscopes can be equipped with standard fluorescence filters to identify single cells very specifically via immunofluorescence. Employing the MMI CellExplorer, target cells can be detected automatically based on their fluorescence signal.

The MMI CellCut laser microdissection system for cutting cells can also be upgraded by the MMI CellEctor to pick single cells from suspension as well as with the MMI CellManipulator to trap cells and to perform force spectroscopy experiments.