Researchers from the Georgia Institute of Technology report that they have developed an analytical tool designed to improve the biomanufacturing process of advanced cell-based therapies.

The team says its Dynamic Sampling Platform provides a real-time analysis of cells as they are modified and grown for treatment in a bioreactor, overcoming what currently is a time-consuming, labor-intensive, and expensive process. The scientists, led by principal investigator Andrei Fedorov, PhD, published their study (“High content drug screening of primary cardiomyocytes based on microfluidics and real-time ultra-large-scale high-resolution imaging”) in Lab on a Chip, a journal of the Royal Society of Chemistry.

“High content screening (HCS) plays an important role in biological applications and drug development. Existing techniques fail to simultaneously meet multiple needs of throughput, efficiency in sample and chemical consumption, and real-time imaging of a large view at high resolution. Leveraging advances in microfluidics and imaging technology, we setup a new paradigm of large-scale, high-content drug screening solutions for rapid biological processes, like cardiotoxicity,” the investigators wrote.

“The designed microfluidic chips enable 10 types of drugs each with five concentrations to be assayed simultaneously. The imaging system has 30 Hz video rate for a centimeter field-of-view at 0.8 μm resolution. Using the HCS system, we assayed 12 small molecules through their effects on the Ca2+ ion signal of cardiomyocytes. Experimental results demonstrated the unparalleled capability of the system in revealing the spatiotemporal patterns of Ca2+ imaging of cardiomyocytes, and validated the cardiotoxicity of certain molecules.

The cell processing device has a channel as thin as human hair through which cells flow. They are captured by the cell immobilization features, rinsed, and then lysed (popped open) by applying electrical pulses. The gold on top of the device are integrated electrodes that line the channel. These electrodes apply the pulses needed for lysis. After lysis, the biochemicals flow out of the device and into the mass spectrometer for analysis. [Georgia Tech]
“We envision that this new HCS paradigm and cutting-edge platform offer the most advanced alternative to well-plate-based methods.”

“There’s a lot of excitement about these cell therapies because they really are remarkable,” said Fedorov, professor in the George W. Woodruff School of Mechanical Engineering and a member of the Petit Institute for Bioengineering and Bioscience at Georgia Tech. “They offer a complete cure. You had a disease, and now you don’t. The biomanufacturing process requires control of product safety and therapeutic potency. But there is a catch—it is very expensive.”

Fedorov and his team aim to provide insight into cell behavior and the biochemical information needed for process control. The technology they developed may lower the cost of these revolutionary treatments, making them available for a broader population of patients.

The price range for approved cell therapy products is $500,000 to $2 million per treatment, with production driving up the cost.

“You take a few cells that you’ve extracted from a patient or a donor, then modify, and grow what is considered enough, [which] right now [is] about a billion cells,” said Fedorov.

After the cells are harvested, they undergo numerous steps, including modification in a bioreactor, which typically takes about 14 days.

“Often, these treatments are only approved for patients who are near terminally ill,” continued Fedorov. “And the problem is, you don’t really know if the cells have maintained their therapeutic potency. You’re almost at the mercy of luck because the ability to fully monitor a cell’s state as it transitions through the entire process is lacking.”

The absence of suitable process analysis tools is the main bottleneck to mass-market entry for these therapeutics, pointed out Fedorov, contributing to the high cost and representing a significant gap in the biomanufacturing process.

So, he and his colleagues developed a new tool to fill that gap, and it’s about the size of a thumbnail.

Dynamic sampling platform

The biomanufacturing of these advanced cell-based therapies depends on the reliable and reproducible growth of cells and that requires vigilant monitoring and analysis of the chemical soup inside the bioreactor, where cells are multiplying.

“The conventional workflow is very manual—there’s a lot of pipetting and centrifuging, and it’s lots and lots of cells, and it takes a long time,” said Austin Culberson, lead author of the study and a PhD student in Fedorov’s lab. “So, we wondered if we could develop the technology to do it quicker.”

They did. The first generation of the Dynamic Sampling Platform focused on analyzing the biomolecules secreted by cells. It was developed in Fedorov’s lab by former PhD student Mason Chilmonczyk, now a postdoctoral researcher in the lab. Chilmonczyk and Fedorov are in the process of commercializing the technology, and they’ve written about their process analytical tool for cell manufacturing in other journals.

Chilmonczyk developed a microfabricated device that processes samples of the media—the broth of vitamins and growth factors where the cells develop. Culberson took the research a step further, creating another small device that performs an intracellular analysis. Now the team believes it has the tools to probe the chemical activity inside of cells, as well as analyze the surrounding, nutrient-rich broth swimming with cell-secreted biomarkers.

“That combination of information provides a much broader, deeper insight as to what is happening to cells in the bioreactor,” Culberson said.

According to Fedorov, “We’re looking for biomarkers, smaller molecules called metabolites. They should tell us the story of how the cell is doing—is this a good cell, is it following the right growth trajectory; is it differentiating into the appropriate type of cell, developing a capability to target disease? And at the end of the process, does it have potency, and can it be administered to a patient?”

Culberson’s micro-sized cell processing device takes in about 100 cells from the bioreactor. The cells pass through channels as thin as human hair, are then captured, rinsed of the broth, then lysed or popped open by electrical pulses.

“After lysis, we spray those biochemicals into a mass spectrometer for analysis,” said Culberson. “Our goal is to have a fully automated platform, so as you’re setting up your biomanufacturing workflow, you would install the Dynamic Sampling Platform. Then you have fully automated, real-time analysis capabilities to guide and track cell growth.”