Researchers at the Indian Institute of Technology (IIT) Bombay have developed a simple and advanced method to safely and effectively recover laboratory-grown immune cells, which may make T-cell based cancer therapy, especially CAR T-cell therapy, more effective.

In immunotherapy like CAR T-cell, T-cells (a type of immune cell) are extracted from the patient’s blood. After this, they are modified and developed in large numbers in the laboratory and then injected into the patient’s bloodstream, so that they can fight cancer cells.

Since these cells grown outside the body must be safely collected before being put back into the patient, recovering them without harming them is considered an important step in the process. The discovery of safe and effective technologies to keep cells alive and active has long been a major challenge.

“Cell recovery sounds easy on paper, but in practice it is one of the biggest challenges. If healthy cells are not recovered in sufficient numbers, they can neither be tested properly nor can they be used in therapy,” said Prakriti Tayalia, Professor, Department of Biosciences and Bioengineering, IIT Bombay.

To mimic the body’s natural environment, the research team used a special scaffold prepared through a process called ‘electrospinning’. These electrospun scaffolds are like thin mats made of very fine fibers, which look like dense fishing nets.

The researchers grew Jurkat T-cells (a human cell line used for research on T-cell biology, cancer, and HIV) within these scaffolds made of a material called polycaprolactone.

Under the microscope it was found that the cells actively entered the scaffold and became firmly trapped between the fibers. The study also revealed that when cells were extracted with an enzyme called trypsin, a large number of cells died.

In contrast, when the cells were recovered with the help of the relatively mild enzyme ‘accutase’, their survival rate was higher and their behavior was found to be similar to that of healthy T-cells. These cells continued to form clusters, a necessary process before T-cells can divide, and continued to grow well after recovery.