Babesia equi (Laveran 1901) 1. Development in horses and in lymphocyte culture.
Abstract: The vertebrate development of Babesia equi from infected Hyalomma marginatum in Morocco was investigated in vitro and in vivo. It was demonstrated that the sporozoites of B. equi initiate a phase of exo-erythrocytic schizogony in lymphocytes both in vitro and in vivo. On the other hand, sporozoites did not invade erythrocytes in vitro. The complete vertebrate life cycle of B. equi was simulated in vitro, from the invasion of lymphocytes by sporozoites, to the development of macro- and microschizonts, the invasion of erythrocytes by merozoites, and the subsequent intra-erythrocytic schizogony. In the equine host, macro- and microschizonts were detected in lymph node biopsies during the febrile phase on days 12 to 14 after application of ticks. As a result, the taxonomic position of B. equi appears to be uncertain.
Publication Date: 1981-12-01 PubMed ID: 7345686
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- Journal Article
Summary
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This research studies how Babesia equi, a protozoan parasite, develops in horses and in laboratory cultures of lymphocytes. The researchers discovered that the parasite goes through a phase of development within lymphocytes before moving on to infect red blood cells, and that this lifecycle can be replicated in the lab.
Background of the Study
- The research focuses on Babesia equi, a protozoan parasite that is transmitted by ticks and infects horses, causing a disease known as equine piroplasmosis.
- B. equi is known to develop within the host’s erythrocytes or red blood cells, but the early phases of its lifecycle and the mechanisms by which it invades the erythrocytes remained unclear.
Methodology
- The researchers utilized both in vitro (in a test tube or other artificial environment) and in vivo (in a living organism) approaches to study the development of B. equi.
- The test subjects were horses that were infected by Hyalomma marginatum ticks from Morocco, known to carry B. equi.
- In addition, the team also cultured lymphocytes, a type of white blood cell, in the laboratory and introduced B. equi sporozoites into the culture.
Findings
- The study demonstrated that B. equi sporozoites initially infect lymphocytes, initiating a phase of schizogony, or asexual multiplication, in these cells both in vitro and in vivo.
- Contrary to prior assumptions, the sporozoites did not invade erythrocytes directly in the in vitro settings.
- The researchers were able to simulate the entire lifecycle of B. equi, from sporozoite invasion of lymphocytes, development of macro- and microschizonts (various stages in the life cycle of some sporozoan protozoa), invasion of erythrocytes by merozoites (another stage of the parasite), and subsequent schizogony within the erythrocytes.
- In horses, macro- and microschizonts were found in lymph node biopsies during the febrile phase of the disease, which occurred 12 to 14 days after the ticks were applied.
Implications
- The findings challenge established knowledge about the lifecycle and taxonomic classification of B. equi.
- As sporozoites initially infect lymphocytes and convert into the next life stages within these cells before invading erythrocytes, this may have implications for the diagnosis, treatment, and control of equine piroplasmosis.
- The discovery that the entire life cycle of the protozoan can be simulated in vitro also opens up new avenues for further research into B. equi and related parasites.
Cite This Article
APA
Schein E, Rehbein G, Voigt WP, Zweygarth E.
(1981).
Babesia equi (Laveran 1901) 1. Development in horses and in lymphocyte culture.
Tropenmed Parasitol, 32(4), 223-227.
Publication
Researcher Affiliations
MeSH Terms
- Animals
- Babesia / growth & development
- Babesiosis / parasitology
- Horse Diseases / parasitology
- Horses / parasitology
- Host-Parasite Interactions
- Lymphocytes / parasitology
Citations
This article has been cited 18 times.- Schnittger L, Ganzinelli S, Bhoora R, Omondi D, Nijhof AM, Florin-Christensen M. The Piroplasmida Babesia, Cytauxzoon, and Theileria in farm and companion animals: species compilation, molecular phylogeny, and evolutionary insights. Parasitol Res 2022 May;121(5):1207-1245.
- Bishop RP, Kappmeyer LS, Onzere CK, Odongo DO, Githaka N, Sears KP, Knowles DP, Fry LM. Equid infective Theileria cluster in distinct 18S rRNA gene clades comprising multiple taxa with unusually broad mammalian host ranges. Parasit Vectors 2020 May 19;13(1):261.
- Jalovecka M, Hajdusek O, Sojka D, Kopacek P, Malandrin L. The Complexity of Piroplasms Life Cycles. Front Cell Infect Microbiol 2018;8:248.
- Guidi E, Pradier S, Lebert I, Leblond A. Piroplasmosis in an endemic area: analysis of the risk factors and their implications in the control of Theileriosis and Babesiosis in horses. Parasitol Res 2015 Jan;114(1):71-83.
- Tian ZC, Liu GY, Yin H, Luo JX, Guan GQ, Luo J, Xie JR, Shen H, Tian MY, Zheng JF, Yuan XS, Wang FF. RPS8--a new informative DNA marker for phylogeny of Babesia and Theileria parasites in China. PLoS One 2013;8(11):e79860.
- Ramsay JD, Ueti MW, Johnson WC, Scoles GA, Knowles DP, Mealey RH. Lymphocytes and macrophages are infected by Theileria equi, but T cells and B cells are not required to establish infection in vivo. PLoS One 2013;8(10):e76996.
- Kappmeyer LS, Thiagarajan M, Herndon DR, Ramsay JD, Caler E, Djikeng A, Gillespie JJ, Lau AO, Roalson EH, Silva JC, Silva MG, Suarez CE, Ueti MW, Nene VM, Mealey RH, Knowles DP, Brayton KA. Comparative genomic analysis and phylogenetic position of Theileria equi. BMC Genomics 2012 Nov 9;13:603.
- Kampen H, Poltz W, Hartelt K, Wölfel R, Faulde M. Detection of a questing Hyalomma marginatum marginatum adult female (Acari, Ixodidae) in southern Germany. Exp Appl Acarol 2007;43(3):227-31.
- Samuel T, Böse R. The 18 kDa antigen of Theileria equi is a specific but less abundant protein also expressed by parasites cultured in vitro. Vet Res Commun 2001 Apr;25(3):169-78.
- Homer MJ, Aguilar-Delfin I, Telford SR 3rd, Krause PJ, Persing DH. Babesiosis. Clin Microbiol Rev 2000 Jul;13(3):451-69.
- d'Oliveira C, van der Weide M, Jacquiet P, Jongejan F. Detection of Theileria annulata by the PCR in ticks (Acari:Ixodidae) collected from cattle in Mauritania. Exp Appl Acarol 1997 May;21(5):279-91.
- Knowles DP Jr, Kappmeyer LS, Perryman LE. Specific immune responses are required to control parasitemia in Babesia equi infection. Infect Immun 1994 May;62(5):1909-13.
- Zapf F, Schein E. The development of Babesia (Theileria) equi (Laveran, 1901) in the gut and the haemolymph of the vector ticks, Hyalomma species. Parasitol Res 1994;80(4):297-302.
- Zapf F, Schein E. New findings in the development of Babesia (Theileria) equi (Laveran, 1901) in the salivary glands of the vector ticks, Hyalomma species. Parasitol Res 1994;80(7):543-8.
- Zweygarth E, Just MC, de Waal DT. Continuous in vitro cultivation of erythrocytic stages of Babesia equi. Parasitol Res 1995;81(4):355-8.
- Rehbein G, Zweygarth E, Voigt WP, Schein E. Establishment of Babesia equi-infected lymphoblastoid cell lines. Z Parasitenkd 1982;67(1):125-7.
- Gupta KK, Gupta N, Kumar S, Srivastava M, Kumar P. Equine piroplasmosis: an emerging tick-borne threat to equine health. Trop Anim Health Prod 2026 Jan 5;58(1):29.
- Matulis G, Potter AM, Lilak AA, Pecor DB, Rodriguez D, Wood L, Cerimele R, Stone K, Cleary NG, Butler K, Linton YM, von Fricken ME. A compilation of ticks and tick-borne pathogen distributions in seven countries within North and West Africa from 1901 to 2022: a systematic literature review. Parasit Vectors 2025 Dec 4;19(1):13.
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