Effect of cancer-induced hemodynamic changes on single leukocyte dynamics in a venule using the Object-in-Fluid (OIF) module.

This study investigates how cancer-induced alterations affect blood flow properties and the dynamics of a single leukocyte with modified mechanical characteristics, compared to a healthy leukocyte, within a venule. Simulations were performed using the ESPResSo package with the Object-in-Fluid (OIF) module. Cell mechanics were modeled with a spring-network membrane, and fluid-structure interactions were handled via force coupling. Base fluid parameters, including viscosity and hematocrit for breast cancer patients, were taken from experimental and clinical data reported in the literature, and the Navier-Stokes equations were solved under laminar flow at low Reynolds numbers. The results show that cancer-induced softening increases leukocyte deformability, enlarges the contact region, and enhances adhesion stability, thereby promoting prolonged wall attachment compared to a healthy leukocyte. Conversely, due to greater deformation and reduced cross-stream height, the cancer-affected leukocyte produces a weaker hydrodynamic obstruction, leading to a smaller reduction in peak flow velocity and a milder modification of wall shear rate. These findings indicate that cancer-driven biomechanical changes exert a dual effect on leukocyte-wall interactions, simultaneously facilitating adhesion while diminishing local hemodynamic perturbations. Overall, the study highlights the utility of OIF simulations for investigating leukocyte dynamics and hemodynamics in venules with cancer-affected blood flow.