Rosette-induced separation of T cells by acoustophoresis

Abstract

Breakthrough cell therapies for the treatment of cancers require the separation of specific cells, such as T cells, from the patient's blood. Current cell therapy processes rely on magnetic separation, which adds clinical risk and requires elevated manufacturing controls due to the added foreign material that constitutes the magnetic beads. Acoustophoresis, a method that uses ultrasound for cell separation, has demonstrated label-free enrichment of T cells from blood, but residual other lymphocytes limit the ultimate purity of the output T cell product. Here, to increase the specificity of acoustophoresis, we use affinity reagents to conjugate red blood cells with undesired white blood cells, resulting in a cell–cell complex (rosette) of increased acoustic mobility. We achieve up to 99% purity of T cells from blood products, comparable to current standards of magnetic separation, yet without the addition of separation particles.

Microparticles with tunable, cell-like properties for quantitative acoustic mechanophenotyping

“…Interestingly, the average NK acoustic contrast was statistically greater than the low-migration cells from the two white blood cell experiments, when assuming the same size for all lymphocyte subtypes. This agrees with recently reported results on acoustic migration of lymphocyte subpopulations, where NK cells experienced greater acoustic mobility compared to T and B lymphocytes 25 .…”

Red blood cell rosetting enables size-based separation of specific lymphocyte subsets from blood in a microfluidic device

“…22 A more recent study (published during revision of this article) used RBC rosetting to improve the separation efficiency of an acoustophoresis device, which was able to separate T cells from mononuclear cell leukapheresis units with purity of ∼85% and recovery of ∼67% at a flow rate of 0.1 mL min −1 . 23 The RESIZE separation method offers several important advantages: (1) the desired lymphocyte subset is separated via 'negative selection' and therefore the cells of interest are unaffected, maintaining high viability and minimal activation after the separation process. (2) The method achieves competitive separation purity (60-90%) and recovery (>80%) at a flow rate that is at least 5-fold higher than demonstrated in the previous studies.…”