U.S. scientists have shown that measuring the buoyant mass of T cells can help predict patient response to immune checkpoint blockade (ICB) immunotherapy.
The team from the Massachusetts Institute of Technology (MIT) showed that measuring the buoyant mass of T cells predicted patient response more accurately than a traditional tumor mutational burden (TMB) approach.
According to the researchers, the new technique could be used not only to predict cancer cell sensitivity to treatment, but also to address the productivity of cell cultures used in gene therapy manufacturing.
“We’ve wanted to show people this is a new physical marker that predicts the fate of the T cells,” explains Jiaquan Yu, PhD, a research scientist working in microfluidic engineering and cancer immunology at MIT.
“By fate, we mean we measure the naïve state of the T cells and get an indication of how they will behave after activation.”
The team used suspended microchannel resonator (SMR) technology, a specialized instrument that uses a vibrating sensor containing a microfluidic channel to measure buoyant mass, Yu says.
The buoyant mass of the T cells is measured relative to water and from the buoyant mass, they were able to calculate the immune fitness of the cells, Yu continues. And, thus, whether they were likely to activate to fight cancer as part of treatment with ICB immunotherapy.
“For T cells, being in the heavier group suggests you’re better equipped to produce proteins,” Yu says. “And that capacity gives us an indication of the fitness of the cells and their ability to respond after activation.”
The team was able to test the performance of the technique in a clinical study of 28 patients with melanoma receiving ICB, Yu explains. And, in that study, they were able to prove that measuring buoyant mass was more effective than TMB at predicting treatment response.
“People are underestimating simple non-molecular signatures, such as mass, volume, and density, as we’re all focused on biomarkers focused on genes and RNA,” Yu says.
“What we’re showing here is that mass gives a result that integrates a lot of information.”