Study: Microfluid Platform Can Help Screen Novel DLBCL Therapies

A scientist working with microfluidic devices

Image credit: Наталья Евтехова - stock.adobe.com

A new report suggests a microfluid platform could be a meaningful tool to screen potential new therapies for diffuse large B-cell lymphoma (DLBCL).

The study was based on an evaluation using the R-CHOP (rituximab [Rituxan] plus cyclophosphamide, hydroxydaunomycin, Oncovin [vincristine sulfate], and prednisone) chemotherapy regimen. The report was published in Cell Death & Disease.

R-CHOP has long been the standard of care for DLBCL. However, up to half of patients will relapse, so additional therapies are needed, said the study authors. Unfortunately, developing and testing new therapies is costly and challenging. One reason for the difficulty, they said, is that current in vitro screening models are 2D and therefore fail to accurately reflect the real-world 3D arrangement of DLBCL in a cancerous lymph node.

“Treatments that appear highly effective in vitro frequently do not translate to in vivo models or clinical success,” they said. “Utilizing 3D in vitro models to better recreate the metastatic lymph node microenvironment is therefore logical to better screen potential treatments for DLBCL before dedicating resources to in vivo models.”

Most of the previous attempts to develop a 3D model have had significant shortcomings, the authors said. But they believe their new approach can succeed.

“To create an improved platform for culturing and testing DLBCL, we applied our previously demonstrated droplet-based microfluidic spheroid model,” they wrote. “This device combines 1000 droplet docking sites with an alginate-based hydrogel to create aqueous-in-oil droplets laden with cells that can be cross-linked, continuously perfused, and imaged on-chip.”

They said one important feature of this platform is the continuous perfusion, which allows for the delivery of relevant nutrients and treatment conditions.

“In addition, this device allows for both real-time monitoring on-chip as well as downstream analysis through recollection of cells and continuous collection of secretions from the device’s array outlet,” they said.

To assess the platform, they used primary human DLBCL along with primary natural killer (NK) cells, treating them with rituximab, CHOP, or a combination of both. They said they chose to add NK cells because they can function independently of antigen-presenting cells and they are the most prominent immune cells in the DLBCL microenvironment.

The authors evaluated several criteria, including cellular viability in response to treatment, rheological properties, and cell surface marker expression levels to see if their results would match what would be expected in vivo. They also measured changes in cellular secretions and transcriptomics.

“Our results showed complex changes in phenotype and transcriptomic response to treatment stimuli, including numerous metabolic and immunogenic changes,” they said. “These findings support this model as an optimal platform for the comparative screening of novel treatments.”

Moreover, they said said their model helps explain problems with traditional plate assays. For instance, they said the level of efficacy observed when samples were treated with rituximab alone was much higher in their plate assays than what has been seen in clinical data.

“These results may be influenced by the drastically reduced expression of CD20 in spheroids compared to expression seen in DLBCL cells taken directly from culture…” they said. “Ultimately, these findings suggest a traditional plate assay produces data that contradicts clinical responses and is less reproducible than our 3D model.”

The investigators said their findings are important because they suggest that it could be possible to more accurately screen and tailor potential novel immunotherapies with results that are much more reliable than current 2D models.

“Given the extensive variety of novel therapies and combinatorial approaches for treating lymphoma, enhanced models for early screening are essential to expedite and improve the quality of early drug,” they said.

Reference

Sullivan MR, White RP, Dashnamoorthy Ravi, et al. Characterizing influence of rCHOP treatment on diffuse large B-cell lymphoma microenvironment through in vitro microfluidic spheroid model. Cell Death Dis. Published online January 9, 2024. doi:10.1038/s41419-023-06299-6