BackgroundMalaria is still a major health problem in sub-Saharan Africa and south-east Asia, but research on malaria in low-income countries can be a challenge due to the lack of laboratory equipment. In addition, severe malaria mainly affects very young children, which limits the amount of blood available for research purposes. Thus, there is a need for protocols that yield a maximum of information from a minimum amount of blood, which are operable in basically equipped laboratories.ResultsA protocol for tandem B and T helper (Th) cell isolation directly from whole blood, and a freezer-independent sample preservation method compatible with the warm and humid climate of malaria regions was established and validated. The protocol thereby circumvents the need of high-technology centrifuges and unimpeachable power supply for peripheral blood mononuclear cell isolation. Both purity and yield are excellent. Depending on the expression level of the genes of interest, between 2 and 5 ml of blood are adequate for reliable qRT-PCR results from both B and Th cells of healthy paediatric donors as well as paediatric malaria patients.ConclusionThis protocol for high purity high yield B cell and Th cell isolation and sample storage for subsequent qRT-PCR analysis from a minimal amount of blood is contrivable with basic equipment and independent of continuous power supply. Thus, it is likely to be of avail for many scientists performing malaria research in rural institutes or hospitals, and thus in countries where malaria is most prevalent.

Endemic Burkitt lymphoma (eBL) is characterized by an oncogenic IGH/c-MYC translocation and Epstein-Barr virus (EBV) positivity, and is epidemiologically linked to Plasmodium falciparum malaria. Both EBV and malaria are thought to contribute to eBL by inducing the expression of activation-induced cytidine deaminase (AID), an enzyme involved in the IGH/c-MYC translocation. AID/apolipoprotein B mRNA editing catalytic polypeptidelike (AID/APOBEC) family enzymes have recently emerged as potent mutagenic sources in a variety of cancers, but apart from AID, their involvement in eBL and their regulation by EBV and P. falciparum is unknown. Here, we show that upon inoculation with EBV, human B cells strongly upregulate the expression of enzymatically active APOBEC3B and APOBEC3G. In addition, we found significantly increased levels of APOBEC3A in B cells of malaria patients, which correlated with parasite load. Interestingly, despite the fact that APOBEC3A, APOBEC3B, and APOBEC3G caused c-MYC mutations when overexpressed in HEK293T cells, a mutational enrichment in eBL tumors was only detected in AID motifs. This suggests that even though the EBV-and P. falciparum-directed immune response triggers the expression and activity of several AID/APOBEC members, only the upregulation of AID has oncogenic consequences, while the induction of the APOBEC3 subfamily may primarily have immunoprotective functions.