Provide Human Reticulocytes for in vitro Culturing of Malaria Parasites

The parasite Plasmodium vivax, transmitted by the Anopheles mosquito, is the second major cause of malaria worldwide. Research focusing on P. vivax has been hindered by lack of a practical continuous culture system as the parasite preferentially invades young erythrocytes (reticulocytes), which are difficult to obtain routinely and in high enough numbers. To address this critical need, ChromoLogic, LLC proposed and developed genetically engineered cells bearing the features of artificial reticulocytes (ArtRet) so as to provide the Army with surrogate cells that are capable of being invaded by the P. vivax malaria and ensure long term culturing of the parasite. The ArtRet prototype system was able to combine the construction and production of lentiviral vectors with transduction of four different erythroleukemic cell lines for delivery of certain genes that confers phenotypes that render them more desirable for invasion and growth of the parasite. Fluorescence-activated cell sorting of cells based on reporter gene expression allowed enrichment of transduced populations. Thus this proof-of-concept has demonstrated success criteria in the feasibility of producing log9 to log10 surrogate host cells capable of continuous and consistent self-renewal and bearing essential phenotypes that allow cost-effective maintenance of the blood-stage P. vivax parasite in culture.