Role of C–C chemokine receptor type 5 in pathogenesis of malaria and its severe forms

Malaria is a mosquito-borne disease caused by Plasmodium parasites, responsible for a significant impact on public health in several tropical and sub-tropical countries. The majority of infection cases are classified as uncomplicated malaria, causing mild symptoms such as fever and headache. However, the disease may progress to severe malaria and death if the infection is not properly treated. Furthermore, malaria poses a major concern for children, pregnant women and immunosuppressed individuals. Exacerbated inflammation is characteristic of severe malaria cases. The C–C chemokine receptor type 5 (CCR5) is an important molecule for leukocyte migration and regulation of inflammation. Although widely known as an HIV-1 co-receptor, CCR5 also affects the susceptibility and progression of autoimmune and inflammatory diseases. There is evidence supporting the participation of CCR5 in malaria manifestations, with the evaluation of CCR5 gene expression levels suggested as a marker to monitor malaria severity. Certain genetic variants in the CCR5 gene affect CCR5 expression, potentially altering CCR5-mediated inflammatory responses during malaria infection. However, the complex influences of CCR5 on malaria remain underexplored. Therefore, this review examines and updates the role of CCR5 in various contexts of malaria infection, including uncomplicated malaria, Plasmodium/HIV co-infection, pregnancy and severe (cerebral) malaria.