In vitro cultivation of Babesia duncani (Apicomplexa: Babesiidae), a zoonotic hemoprotozoan, using infected blood from Syrian hamsters (Mesocricetus auratus)
Human babesiosis, a tick-borne disease similar to malaria, is most often caused by the hemoprotozoans Babesia divergens in Europe, and Babesia microti and Babesia duncani in North America. Babesia microti is the best documented and causes more cases of human babesiosis annually than all other agents combined. Although the agents that cause human babesiosis are considered high-risk pathogens in transfusion medicine, federally licensed diagnostics are lacking for B. duncani in both the USA and Canada. Thus, there has been a need to develop and validate diagnostics specifically for this pathogen. In this study, B. duncani (WA1 isolate) was cultivated in vitro from Syrian hamster (Mesocricetus auratus) infected blood. We hypothesized HL-1 media with supplements would result in B. duncani propagating at higher levels in culture than supplemented M199 similar to the medium the parasite was originally cultivated with in 1994. We were unable to recreate Thomford’s cultivation results with the M199 medium but supplemented HL-1 medium was able to successfully establish continuous culture. We further hypothesized that RBC from species other than hamsters would support B. duncani in vitro. However, rat, mouse, horse, and cow RBC did not support continuous culture of the parasite. Culture stocks of B. duncani were deposited at BEI Resources and are now commercially available to the scientific community to further research. The cultured parasite developed in this study was instrumental in the adaptation of B. duncani continuous culture to human RBC.
KeywordsBabesia duncani Human babesiosis Transfusion Tick-borne disease Percentage of parasitized erythrocytes (PPE)
Compliance with ethical standards
All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. All procedures performed in studies involving animals were in accordance with the ethical standards of Texas A&M University at which the studies were conducted.
Conflict of interest
The authors declare that they have no conflict of interest.
- Abraham A, Brasov I, Thekkiniath J, Kilian N, Lawres L, Gao R, DeBus K, He L, Yu X, Zhu G, Graham M, Liu X, Molestina R, Ben Mamoun C (2018) Establishment of a continuous in vitro culture of Babesia duncani in human erythrocytes reveals unusually high tolerance to recommended therapies. J Biol Chem 293(52):19974–19981. https://doi.org/10.1074/jbc.AC118.005771 CrossRefGoogle Scholar
- Canning EU, Winger CM (1987) Babesiidae.In: Taylor AER, Baker JR (Eds.) In vitro methods for parasite cultivation. Academic Press, London, pp199–299Google Scholar
- Centers for Disease Control and Prevention (CDC) (2015) 2013 Data archive. https://www.cdc.gov/parasites/babesiosis/data-statistics/2013.html. Accessed 7 Nov 2018
- Centers for Disease Control and Prevention (CDC) (2016) 2012 Data archive. https://www.cdc.gov/parasites/babesiosis/data-statistics/2012.html. Accessed 7 Nov 2018
- Conrad PA, Kjemtrup AM, Carreno RA, Thomford J, Wainwright K, Eberhard M, Quick R, Telford SR, Herwaldt B (2006) Description of Babesia duncani n.sp. (Apicomplexa: Babesiidae) from humans and its differentiation from other piroplasms. Int J Parasitol 36(7):779–789. https://doi.org/10.1016/j.ijpara.2006.03.008 CrossRefGoogle Scholar
- Herwaldt BL, Montgomery S, Woodhall D, Bosserman EA (2012) Babesiosis surveillance – 18 states, 2011. CDC Morbidity and Mortality Weekly Report 61(27):505–509 https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6127a2.htm. Accessed 7 Nov 2018
- Herwaldt BL, Gray EB (2016) Surveillance for Babesiosis – United States, 2014 annual summary. https://www.cdc.gov/parasites/babesiosis/resources/babesiosis_surveillance_summary_2016.pdf. Atlanta, Georgia: U.S. Department of Health and Human Services, CDC. Accessed 7 November 2018
- Innes RJ (2013) Odocoileus hemionus. In: Fire effects information system, [online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). https://www.fs.fed.us/database/feis/animals/mammal/odhe/all.html. Accessed 8 November 2018
- Swei A, O’Connor KE, Couper LI, Thekkiniath J, Conrad PA, Padgett KA, Burns J, Yoshimizu MH, Gonzales B, Munk B, Shirkey N, Konde L, Ben Mamoun C, Lane RS, Kjemtrup A (2019) Evidence for transmission of the zoonotic apicomplexan parasite Babesia duncani by the tick Dermacentor albipictus. Int Journ Parasitol 49:95–103. https://doi.org/10.1016/j.ijpara.2018.07.002 CrossRefGoogle Scholar
- Thomford JW, Conrad P, Telford SR, Mathiesen D, Bowman BH, Spielman A, Eberhard ML, Herwaldt BL, Quick RE, Persing DH (1994) Cultivation and phylogenetic characterization of a newly recognized human pathogenic protozoan. J Infect Dis 169(5):1050–1056. https://doi.org/10.1093/infdis/169.5.1050 CrossRefGoogle Scholar
- Texas A&M University System (TAMUS) (2011) The tick app for Texas and the southern region. http://tickapp.tamu.edu/ticks/wintertick.html. Accessed 9 Nov 2018
- United States Food and Drug Administration (USFDA) (2016) Fatalities reported to FDA following blood collection and transfusion: annual summary for fiscal year 2015. http://wayback.archive-it.org/7993/20171114162532/https://www.fda.gov/downloads/BiologicsBloodVaccines/SafetyAvailability/ReportaProblem/TransfusionDonationFatalities/UCM518148.pdf. Accessed 7 Nov 2018
- United States Food and Drug Administration (USFDA) (2017) Fatalities reported to FDA following blood collection and transfusion: annual summary for fiscal year 2016. https://www.fda.gov/downloads/BiologicsBloodVaccines/SafetyAvailability/ReportaProblem/TransfusionDonationFatalities/UCM598243.pdf. Accessed 7 Nov 2018