Naturally Acquired Immunity (NAI)

Abstract

Abbreviations ADCC Antibody-dependent cellular cytotoxicity ADCI Antibody-dependent cellular inhibition CTL Cytotoxic T lymphocytes DC Dendritic cells GPI Glycosylphosphatidylinositol IFN-g Interferon gamma Ig Immunoglobulin IL Interleukin MBC Memory B cells MHC Major histocompatibility complex NAI Naturally acquired immunity NK Natural killer PBMC Peripheral blood mononuclear cell PfSPZ Plasmodium falciparum sporozoites PRBC Parasitized red blood cell SM Severe malaria T FH Thymus follicular helper TGF Tumor growth factor TLR Toll-like receptors TNF Tumor necrosis factor Treg T regulatory Synonyms Definitions Naturally acquired immunity (NAI) refers to the capacity of individuals living in malaria endemic areas to develop an adaptive immunity against Plasmodium infection and disease with age and exposure that protects them against the negative effects caused by the pathogen (Doolan et al. 2009). The pattern of NAI has been better characterized for the most pathogenic species of human malaria, Plasmodium falciparum, which will be the main focus of this encyclopedia chapter. The rate of acquisition and the efficacy of NAI at different ages are dependent upon the intensity and seasonality of the malaria transmission, whereby development of effective NAI mostly occurs in areas of heavy and continuous transmission , generally within sub-Saharan Africa. In these settings, the main epidemiological manifestations of NAI include a reduction in the frequency of deaths and severe malaria (SM) cases that are confined to very young children (mostly age under 1-2 years) and the reduction in the # Springer Science+Business Media LLC 2018 P. G. Kremsner, S. Krishna (eds.), Encyclopedia of Malaria, https://doi.