Graphical representation of antiviral SARS-Coronavirus 2 immunity. B: B lymphocyte; CTL: cytotoxic; T lymphocyte; IFN: interferon; Ig: immunoglobulin; IL: interleukin; MHC: major histocompatibility class; NFκB: nuclear factor kappa-light- chain- enhancer of activated B cells; NK: natural killer cell; Th: helper T lymphocyte; TLR: Toll-like receptor; TNF: tumour necrosis factor