Methylene Blue Treatment of Fatal Cerebral Malaria and Identification of Potential Blood Biomarkers

Cerebral malaria (CM) is a severe complication caused by Plasmodium falciparum infection, leading to persistent neurological impairments in survivors. To understand the complex mechanisms and investigate advanced diagnostic and treatment strategies targeting human CM, we utilize Plasmodium coatneyi-infected male rhesus macaques, a non-human primate model closely resembling P. falciparum infection in humans. Through differential gene expression analysis, our study demonstrates methylene blue's efficacy in reversing the detrimental effects of infection on the brainstem. Furthermore, by comparing our brainstem dataset from P. coatneyi-infected Macaca mulatta with two additional transcriptomic datasets (P. coatneyi-infected M. mulatta blood and P. falciparum-infected human blood), we identify nine genes associated with CM severity. Most of these genes are expressed in neutrophils, indicating their potential as blood biomarkers for diagnosing P. falciparum-induced fatal CM. This research highlights the necessity for new CM treatments and reveals promising biomarkers that could improve diagnosis and prognosis in affected individuals. Overall design: To investigate cerebral malaria biomarkers, we established P. coatneyi (Hackeri strain) infections in Macaca mulatta. Upon cerebral malaria induction, infected macaques were treated with either 6 mg/kg, 10 mg/kg or 17 mg/kg methylene blue. At study endpoint, the organ tissues (brainstem, thalamus, cerebellum, heart, kidney, and liver) of uninfected group (Pcoat-MB-), infected-untreated group (Pcoat+MB-), and infected-treated group (Pcoat+MB+) were harvested for RNA-seq.