University of Illinois Veterinary Student Summer Research Training Program
2008 Mentor Profile
Carol Maddox
Associate Professor,
Pathobiology/Veterinary Diagnostic Laboratory
Project Description:
“Environmental Exposure to Pathogenic Leptospira Serovars"
C.W. Maddox, N. Jung, and S. Lanka - Veterinary Diagnostic Laboratory
For several years we have been successfully using a qPCR technique to detect Leptospira in urine of clinically ill canines with hepatic or kidney disease. How these infections are acquired is often in question. We have explored several risk factors, among them exposure to standing water such as retention ponds or lakes in newer housing developments. However, identifying pathogenic serovars among the mixture of Leptospires and high numbers of other bacteria in water samples has been difficult. Research to identify serovar specific biomarkers that would enable us to genotypically distinguish between the 7 common pathogenic serovars would enable us to obtain important information regarding epidemiology of Leptospirosis and vaccine development. A combination of bioinformatics and hybridization assays could be used to identify target sequences to aid in differentiating between Leptopsira strains.
"Design of Streptococcus Vaccines Using Virulence Gene Sequences"
C.W. Maddox, S. Patterson, P. Hoien-Dalen and L. Borst - Pathobiology
Molecular methods have been used to evaluate virulence genes of Streptococcus equi and Streptococcus zooepidemicus. Discrete deletion mutations have been produced by cloning PCR generated mutated genes. These mutated genes are introduced back into the Strep virulence genes by means of homologous recombination, using temperature sensitive shuttle vectors. Using these deletion mutants, we can investigate the impact of single virulence factors on disease. Initially, recombinants are been screened using a novel zebrafish model of infection to identify possible means of attenuation. Thus far, deletion mutants in the capsule (hasA), superoxide dismutase (sodA), and m-like protein (szp) have been engineered and shown to significantly increase survival time in the zebrafish model. Promising recombinants will next be evaluated in an intranasal mouse model of Streptococcus infection. Humoral responses to potential vaccine candidates can be evaluated and challenge studies performed to assess protective responses to vaccination with attenuated strains.
Dr. Maddox's biosketch page
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