Biological analyses have traditionally been conducted on cell ensembles, leading to key differences in cell proliferation and disease state between individual cells being obscured by the averaging effect of studying a group.
This has hindered the study of cancer progression and immune cell response where even though cells have similar surface markers, they have wildly varying genetic traits that affect their response to stimuli.
This has led to an increased desire for analytical methods that can be used to individually study the cells within an ensemble and gain unique insights into disease pathways.
According to Frank Feist, Executive Director of Olympus’ Advalytix business unit, one of the key hurdles for researchers wishing to conduct single cell molecular analysis has been the integration of single cell analysis systems into existing workflows.
“Advalytix has worked hard to develop the AmpliGrid system so that it slots easily into existing laboratory workflows, making it easy to analyse single cells whether they have been captured via flow sorting methods such as FACS (fluorescence-activated cell sorting), micromanipulation or laser capture microscopy (LCM),” said Feist.
Advalytix’ AmpliGrid slides contain 48 independent hydrophilic reaction sites, each surrounded by a hydrophobic circle designed to hold aqueous reaction solutions in place and stop well to well mixing.
According to Feist, sorting cells into an AmpliGrid slide leads to a placement success of over 95 per cent, compared with only 60-70 per cent when using standard 96 well microtitre plates due to electrostatic deflection of the cells before they reach the well.
The slides are made of glass, enabling researchers to check each well only contains a single cell prior to analysis using microscopy techniques that can be easily automated for high-throughput systems.
Once the cells are in the reactor cells the genomic material they contain can then be amplified before they are analysed using any number of assay technologies including qPCR (quantitative polymerase chain reaction), capillary electrophoresis (CE) and genetic sequencing.
The combination of the AmpliGrid technology with PCR amplification and analysis has enabled researcher at the University Hospital of Jena to type and profile individual circulating tumour cells that have metastasized from breast cancer tumours.
This approach is not possible using traditional techniques as enrichment of the cancer cells still leads to only one cancer cell for every 20 to 50 normal cells.
Feist highlighted how this approach is helping to differentiate cancer stem cells from cancer cells and study the differences in their genetic make-ups.
Cancer stem cells are believed to be tumour-forming stem cells that can self-renew and differentiate into multiple cell types causing relapse and metastasis even after treatment with chemotherapy.
The exact role that this distinct population of cancer cells play in the formation and proliferation of tumours is one of the most active topics in oncology at the moment.
One of the key problems involved with studying cancer stem cells is that tumours are typically heterogeneous and contain multiple cell types native to the host organ, even after metastasis has occurred.
“Rather than conducting a pooled analysis of all the cells in a tumour the AmpliGrid technology enables researchers to study the differences between the individual cells and find ways to specifically target cancer stem cells and cause tumour regression,” said Feist.
He also highlighted how the use of the AmpliGrid system can dramatically reduce reagent costs, incredibly important for high-throughput studies and in forensic laboratories that can run hundreds of thousands of samples a year.