Simulating malaria-infected blood in arterial flow to quantify changes in cell margination and immune suppression*

Malaria stiffens and reshapes red blood cells (RBCs), which changes the cell distribution in the vasculature. When the RBC distribution is disrupted, the ability of white blood cells and platelets to sample the endothelium wall is impeded, and the body’s immune response is affected. In order to study the effect of malaria infection on cell margination and immune suppression, we simulated artery flow as a dense cell suspension using HemoCell, an open-source immersed boundary-lattice Boltzmann method (IB-LBM) code. 

First, we characterized the single RBC cell behavior under tensile and shear force with validation against optical tweezer and flow cytometry data. The characterization established a representative cell for the three stages of the malaria asexual reproduction cycle. Second, we ran dense suspensions of cells with physiologically relevant length and time scales. We analyzed the margination while varying Reynolds number, channel shape, cell type, and disease progression. Our analysis can provide insight into disease severity and what interventions best target the infection.