This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ueti, M. W. Articles by Knowles, D. P. Search for Related Content PubMed PubMed Citation Articles by Ueti, M. W. Articles by Knowles, D. P.

Expression of Equi Merozoite Antigen 2 during Development of Babesia equi in the Midgut and Salivary Gland of the Vector Tick Boophilus microplus

Program in Vector-Borne Diseases, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington 99164-7040,¹ Animal Disease Research Unit, USDA Agricultural Research Service, Pullman, Washington 99164-6630²

Received 15 May 2003/ Returned for modification 19 August 2003/ Accepted 29 August 2003

Equi merozoite antigens 1 and 2 (EMA-1 and EMA-2) are Babesia equi proteins expressed on the parasite surface during infection in horses and are orthologues of proteins in Theileria spp., which are also tick-transmitted protozoal pathogens. We determined in this study whether EMA-1 and EMA-2 were expressed within the vector tick Boophilus microplus. B. equi transitions through multiple, morphologically distinct stages, including sexual stages, and these transitions culminate in the formation of infectious sporozoites in the tick salivary gland. EMA-2-positive B. equi stages in the midgut lumen and midgut epithelial cells of Boophilus microplus nymphs were identified by reactivity with monoclonal antibody 36/253.21. This monoclonal antibody also recognized B. equi in salivary glands of adult Boophilus microplus. In addition, quantification of B. equi in the mammalian host and vector tick indicated that the duration of tick feeding and parasitemia levels affected the percentage of nymphs that contained morphologically distinct B. equi organisms in the midgut. In contrast, there was no conclusive evidence that B. equi EMA-1 was expressed in either the Boophilus microplus midgut or salivary gland when monoclonal antibody 36/18.57 was used. The expression of B. equi EMA-2 in Boophilus microplus provides a marker for detecting the various development stages and facilitates the identification of novel stage-specific Babesia proteins for testing transmission-blocking immunity.

This article has been cited by other articles:

• Ueti, M. W., Reagan, J. O. Jr., Knowles, D. P. Jr., Scoles, G. A., Shkap, V., Palmer, G. H. (2007). Identification of Midgut and Salivary Glands as Specific and Distinct Barriers to Efficient Tick-Borne Transmission of Anaplasma marginale. Infect. Immun. 75: 2959-2964 [Abstract] [Full Text]  
• IKADAI, H., SASAKI, M., ISHIDA, H., MATSUU, A., IGARASHI, I., FUJISAKI, K., OYAMADA, T. (2007). MOLECULAR EVIDENCE OF BABESIA EQUI TRANSMISSION IN HAEMAPHYSALIS LONGICORNIS. Am J Trop Med Hyg 76: 694-697 [Abstract] [Full Text]  
• Ueti, M. W., Palmer, G. H., Kappmeyer, L. S., Statdfield, M., Scoles, G. A., Knowles, D. P. (2005). Ability of the Vector Tick Boophilus microplus To Acquire and Transmit Babesia equi following Feeding on Chronically Infected Horses with Low-Level Parasitemia. J. Clin. Microbiol. 43: 3755-3759 [Abstract] [Full Text]