An Agent-Based Model of Monocyte Differentiation into Tumour-Associated Macrophages in Chronic Lymphocytic Leukemia

Monocyte-derived macrophages help maintain tissue homeostasis and defend the organism against pathogens. In tumors, recent studies have uncovered complex macrophage populations, including tumor-associated macrophages, which support tumorigenesis through cancer hallmarks such as immunosuppression, angiogenesis or matrix remodeling. In the case of chronic lymphocytic leukemia, these macrophages are known as nurse-like cells and they protect leukemic cells from spontaneous apoptosis contributing to their chemoresistance. We propose an agent-based model of monocyte differentiation into nurse-like cells upon contact with leukemic B cells in vitro . We performed patient-specific model calibrations using cultures of peripheral blood mononuclear cells from patients. Using our model, we were able to reproduce temporal survival dynamics of cancer cells in a patient-specific manner and to identify patient groups related to distinct macrophage phenotypes. Our results show a potentially important role of phagocytosis in the polarization process of nurse-like cells and in promoting cancer cells’ enhanced survival.