Application of antibodies to recombinant heat shock protein 70 in immunohistochemical diagnosis ofmycobacterium avium subspecies paratuberculosisin tissues of naturally infected cattle.
BACKGROUND
Detection ofMycobacterium avium subspecies paratuberculosis(MAP) infection is key to the control of Johne's disease. Immunohistochemistry is one of the methods of detection of MAP infection in tissues. However, unavailability of commercial antibodies that can detect the organism is a limiting factor for the use of immunohistochemistry. This study was aimed at developing an immunohistochemistry method to diagnose MAP in infected tissues using antibodies against MAP recombinant heat shock protein 70kd.


RESULTS
MAP Heat shock protein 70 gene was amplified and cloned into an expression vector, Champion pET-SUMO, then expressed inE coli, purified and used to produce polyclonal rabbit antibodies against the Heat shock protein. Immunohistochemistry was performed in 35 MAP infected tissues with anti-HSP70 polyclonal antibodies. All 35 MAP infected tissues were positive for MAP within macrophages, epithelioid cells and giant cells either in clumps or singly as individual bacilli. No positive staining was seen in the three uninfected normal tissues and in MAP infected tissues where primary antibodies were substituted with PBS or pre-immune serum from the same rabbit.


CONCLUSIONS
Anti-HSP70 produced in this study offers an opportunity for improved diagnosis, screening of MAP in animal tissues and in studies on the pathogenesis of MAP.
College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda.
Julius Boniface
JB
Okuni
College of Health Sciences, Makerere University, P.O. Box 7072, Kampala, Uganda.
David Patrick
DP
Kateete
College of Health Sciences, Makerere University, P.O. Box 7072, Kampala, Uganda.
Moses
M
Okee
College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda.
Anna
A
Nanteza
College of Health Sciences, Makerere University, P.O. Box 7072, Kampala, Uganda.
Moses
M
Joloba
College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, P.O. Box 7062, Kampala, Uganda.
Lonzy
L
Ojok
HSP70; Immunohistochemistry; Johne’s disease; Mycobacterium avium subspecies paratuberculosis