Multiparametric biophysical profiling of red blood cells in malaria infection

Abstract

Biophysical separation promises label-free, less-invasive methods to manipulate the diverse properties of live cells, such as density, magnetic susceptibility, and morphological characteristics. However, some cellular changes are so minute that they are undetectable by current methods. We developed a multiparametric cell-separation approach to profile cells with simultaneously changing density and magnetic susceptibility. We demonstrated this approach with the natural biophysical phenomenon of Plasmodium falciparum infection, which modifies its host erythrocyte by simultaneously decreasing density and increasing magnetic susceptibility. Current approaches have used these properties separately to isolate later-stage infected cells, but not in combination. We present biophysical separation of infected erythrocytes by balancing gravitational and magnetic forces to differentiate infected cell stages, including early stages for the first time, using magnetic levitation. We quantified height distributions of erythrocyte populations—27 ring-stage synchronized samples and 35 uninfected controls—and quantified their unique biophysical signatures. This platform can thus enable multidimensional biophysical measurements on unique cell types.

Automated Recognition of Plasmodium falciparum Parasites from Portable Blood Levitation Imaging

“…Levitation Suspension of Blood Cells in a Microscale Environment: The magnetic levitation platform, as pictured in Figure 1B,C, was a compact device that levitates cells in a prepared solution, shown to be capable of separating various cell types such as cancer cells from blood cells, including cultured ring-stage P. falciparum-infected RBCs from uninfected RBCs as shown in a previous work. [42,63] The solution was prepared with saponin (for lysis) and non-cytotoxic chelated gadolinium ions (for levitation) in phosphate buffered saline (PBS) solution. The cells were suspended in this solution as in Figure 1B, with further reagents added per experimental needs, within a square channel in the magnetic field created between two permanent magnets.…”

Basic Principles and Recent Advances in Magnetic Cell Separation

“…While we have focused our attention here on the widely explored fields of CTCs and pathogen detection, there are many other applications related to magnetic separation, such as detection of malaria-infected cells [288][289][290][291][292], peripheral blood lymphocytes sorting in different T cell subsets for immunotherapy [293,294], cell counting for disease…”

“…While we have focused our attention here on the widely explored fields of CTCs and pathogen detection, there are many other applications related to magnetic separation, such as detection of malaria-infected cells [288][289][290][291][292], peripheral blood lymphocytes sorting in different T cell subsets for immunotherapy [293,294], cell counting for disease monitoring [295], as well as phenotypic cell sorting. The Kelley group has developed several microfluidic devices for high-throughput analysis based on the MagRC concept (see Section 4.2.2).…”

Multi-Omics Analysis of Magnetically Levitated Plasma Biomolecules

“…Magnetic levitation of diamagnetic materials/objects in paramagnetic solutions is a well-documented density-based analysis and separation technique that has been used for a wide range of biological applications from cell sorting and tissue engineering to bone regeneration and self-assembly of living materials. (Abrahamsson et al 2020;Baday et al 2019;Deshmukh et al 2021;Durmus et al 2015;Gao et al 2022;Ozefe and Arslan Yildiz 2020;Parfenov et al 2020a;Parfenov et al 2020b;Puluca et al 2020;Sözmen and Arslan-Yıldız 2022;Tasoglu et al 2013;Tasoglu et al 2015;Tocchio et al 2018;Yang et al 2019) However, this technique cannot levitate nanoscale biomolecules (e.g., plasma proteins), at least in part, due to i) the Brownian motion effect, and ii) the instability of the biomolecules arising from their interactions with high concentrations of conventional paramagnetic salts (e.g., GdCl3 and MnCl2). (Ashkarran and Mahmoudi 2021) , (Ashkarran et al 2020b) To overcome these limitations, we recently introduced superparamagnetic iron oxide nanoparticles (SPIONs), constituting a novel paramagnetic liquid that is able to minimize Brownian motion and reliably/reproducibly levitate plasma biomolecules.…”