Profile of Natural Killer (NK) Cells in Simple Malaria in Adults

Abstract

Justification: In the problematic of protection against severe forms of malaria, premunition has often been mentioned as a protective factor acquired in adults at the cost of multiple infections for several years. Exploration of the cellular component of anti-parasite immunity in uncomplicated malaria will provide comparisons of evidence that, despite relative protection, 2 to 3% of adults living in the endemic zone are victims of severe malaria. Main objective: The objective was to evaluate the role of the innate cellular response in susceptibility to uncomplicated malaria in subjects older than 15 years. Patients and Methods: It was a prospective study with descriptive and analytical purpose that took place at Koumassi General Hospital for simple malaria patients and the NBTC for witnesses. All blood samples were analyzed in the Immunology and Hematology Laboratory of CHU de Cocody. It included 50 patients (25 patients with malaria and 25 witnesses) of both sexes, over a 3-month period. The samples carried were processed in the said-laboratory. Results: The average age of our patients was 35 years. The mean of NK cells were 45 cells/mm3 in patients and 154.64 cells/ mm3 in witness persons. The risk of not seeing a simple malaria when the number of NK cells is high was 9.03. The PPV was 88.88% and the NPV was 62.6%. The mean parasitemia in patients was 1840 trophozoites/μL. The influence of NK cells on parasitemia was undetermined with a PPV at 1% and a NPV at 39.13%. Conclusion: Susceptibility to simple malaria is a multifactorial phenomenon in which the immune response plays a central role. The evolution towards this clinical state will have to be studied with all the other cellular actors to better appreciate the role of NK cells during its evolution.