Modelling Neutrophils’ Response to Various Levels of Insults

Abstract

Neutrophils are one of the key players in the human innate immune system. Depending on the level of insult, neutrophils are activated and could either go into apoptosis or necrosis. Apoptosis or programmed death of neutrophils poses benefits to the human body through anti-inflammatory effects. Necrosis, on the other hand, triggers the rupture of the cell, spilling all of its contents in the surrounding tissue thus aggravating the level of inflammation as it already is. This, however indirectly triggers the recruitment of more activated neutrophils into the site of inflammation. Despite the risk on the body, the human innate immune system still chooses to do so. We model this delicate balance between apoptosis and necrosis as the innate immune system in order to resolve inflammation through game theory coupled with cellular automata motivated by the idea that one part of the body centered at a neutrophil is playing a game, much like a rational individual, with another part of the body, based on payoffs proportional to the initial concentration of inflammation triggering moieties. We show that the body prefers apoptosis with decreasing inflammation triggering moieties (ITMs) concentration. However, as the concentration of ITMs increases, the body shifts its equilibrium to necrosis.