Gluck Center > Directory > Gluck Faculty >Howe, DK
Daniel K. Howe, Ph.D.
Gluck Equine Research Center
My research interests are focused on molecular studies of the Coccidia, which are a very significant group of protozoan pathogens that includes the human parasite Toxoplasma gondii and the domestic animal parasites Neospora spp., Eimeria spp., and Sarcocystis spp. Our particular emphasis is on Sarcocystis neurona, the primary causative agent of equine protozoal myeloencephalitis (EPM).
EPM is one of the most common neurologic diseases of horses in North America. It is also one of the more enigmatic equine disorders that continues to be difficult to accurately diagnose, prevent, and treat. A primary objective for my research program is to resolve deficiencies in molecular data on Sarcocystis neurona, and to utilize this information to improve our ability to understand and control EPM.
To help define the molecular composition of S. neurona, we have conducted an expressed sequence tag (EST) sequencing project that has produced over 15,000 partial gene sequences from two different EPM isolates of S. neurona. An additional 6000+ sequences have been generated from the closely-related parasite Sarcocystis falcatula. The S. neurona sequence data can be accessed at the URL http://compbio.dfci.harvard.edu/tgi/cgi-bin/tgi/gimain.pl?gudb=s_neurona.
We are currently exploring the sequence information produced by the S. neurona EST project to discover important parasite genes. Thus far, this approach has allowed us to identify and characterize a gene family of major parasite surface antigens, which we designated as SnSAGs, and several parasite secretory antigens. We are now investigating the biological characteristics of these proteins to gain insight into their role as parasite virulence factors.
Additionally, we have designed enzyme-linked immunosorbent assays (ELISAs) based on the S. neurona surface antigens. These SnSAG ELISAs will accurately detect S. neurona antibodies in equine serum and cerebrospinal fluid, thereby providing tests that reliably identify animals exposed to S. neurona. Additionally, these assays are being used as research tools to assess equine immune responses during parasite infections and the progression to neurologic disease.
Maxwell H.Gluck Equine Research Center
Department of Veterinary Science, University of Kentucky
Lexington, Kentucky 40546-0099
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