Figure 4 Lifestyle and environmental factors affect the immune system to trigger and/or perpetuate multiple sclerosis Figure 4 | Lifestyle and environmental factors affect the immune system to trigger and/or perpetuate multiple sclerosis. Depicted here are lifestyle and environmental factors that can affect immune system function, which can lead to neuroinflammatory attack on the CNS and eventually lead to multiple sclerosis. APC, antigen-presenting cells; Ab, antibody; C, complement; CMV, cytomegalovirus; EBV, Epstein–Barr virus; GM-CSF, granulocyte monocyte colony stimulating factor; myelin-Ag, myelin antigens; NO, nitric oxide; ROS, reactive oxygen species; TC, T cytotoxic cell; TGF-β, transforming growth factor β; TH, T helper cell; TNF, tumour necrosis factor; TS, T suppressor cell. Olsson, T. et al. (2016) Interactions between genetic, lifestyle and environmental risk factors for multiple sclerosis Nat. Rev. Neurol. doi:10.1038/nrneurol.2016.187