In Silico Study of Formation and Collapse of T-Killer Cell Synapse Mediated by Receptor Recycling and Actin Network

T-killer cells of the immune system eliminate virus-infected and tumorous cells through direct cell to cell interactions. Reorientation of the killing apparatus inside the T-killer cell to the interface with the target cell ensures specificity of the immune response. Several research works were reported to explain the mechanism of reorientation but the most adversary situation, when the cell's initial orientation is complete opposite to the desirable direction, always left skepticism toward the suggested mechanism. We have constructed a computational model that incorporate T-killer cell receptor dynamics and all the possible mechanical properties which involve not only intrinsic physiology of T-killer cell but also the synapse formation with target cell. The model studies show that the actin network nucleation and degradation is a crucial part in the T-killer cell synapse formation. Furthermore, the role of actin network provides a safety feature for the T-cell reorientation mechanisms by allowing T-cells to detach from the target cell when they are stranded in situations in which reorientation is not available. Our computational model also provides insights into the actin network near the T-cell synapse including retrograde flow development.