Figure 2.

Simplified outline of immune responses in malaria and infections. Innate immune response in both malaria and COVID-19 begins with involving antigen-presenting cells, macrophages, dendritic cells and natural killer cells resulting in a sharp blowout of pro-inflammatory cytokines including IL-6, TNF and IFN promoted to inhibit pathogen proliferation. These pro-inflammatory cytokines are regulated by anti-inflammatory cytokines such as IL-10 and TGF-b to reduce the severity and increase the ability of tissues to tolerate inflammatory damage. CD8+ TC lymphocytes, including memory cells, recognize pathogen epitopes and cross-reactive epitopes from related pathogens leading to the effective killing. Antibodies are produced to prevent the pathogen from invasion of infected cells and the cytoadherence which could result in opsonization and subsequent phagocytosis. IgG is the major antibody that prompts this cascade of immune reactions.