Direct contact between Plasmodium falciparum and human B-cells in a novel co-culture increases parasite growth and affects B-cell growth

Malaria Journal

Mats Wahlgren¹  Sreenivasulu B. Reddy¹  Francesca Chiodi¹  Frank Heuts¹  Noemi Nagy¹  Laszlo Szekely¹  Caroline Rönnberg²  Kristina E. M. Persson³  Allan Lugaajju⁴ 

[1] Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden;Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden;Department of Clinical Microbiology, Karolinska University Hospital, Huddinge, Stockholm, Sweden;Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden;Department of Laboratory Medicine, Skåne University Hospital, Lund University, Lund, Sweden;Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden;Makerere University, Kampala, Uganda;

关键词: Malaria;    Plasmodium falciparum;    B-cell;    Human;    Culture;   

DOI  :  10.1186/s12936-021-03831-x

来源: Springer

【 摘 要 】

BackgroundPlasmodium falciparum parasites cause malaria and co-exist in humans together with B-cells for long periods of time. Immunity is only achieved after repeated exposure. There has been a lack of methods to mimic the in vivo co-occurrence, where cells and parasites can be grown together for many days, and it has been difficult with long time in vitro studies.Methods and resultsA new method for growing P. falciparum in 5% CO2 with a specially formulated culture medium is described. This knowledge was used to establish the co-culture of live P. falciparum together with human B-cells in vitro for 10 days. The presence of B-cells clearly enhanced parasite growth, but less so when Transwell inserts were used (not allowing passage of cells or merozoites), showing that direct contact is advantageous. B-cells also proliferated more in presence of parasites. Symbiotic parasitic growth was verified using CESS cell-line and it showed similar results, indicating that B-cells are indeed the cells responsible for the effect. In malaria endemic areas, people often have increased levels of atypical memory B-cells in the blood, and in this assay it was demonstrated that when parasites were present there was an increase in the proportion of CD19 + CD20 + CD27 − FCRL4 + B-cells, and a contraction of classical memory B-cells. This effect was most clearly seen when direct contact between B-cells and parasites was allowed.ConclusionsThese results demonstrate that P. falciparum and B-cells undoubtedly can affect each other when allowed to multiply together, which is valuable information for future vaccine studies.

【 授权许可】

CC BY