Localization of a 56-kDa antigen that is present in multiple developmental stages of Neospora caninum.
The purpose of the present study was to characterize the intracellular distribution of a native Neospora caninum 56-kDa protein that is recognized by sera from N. caninum-infected dairy cattle. The complementary DNA coding for this protein was expressed in Escherichia coli as a polyHis fusion protein to which antiserum was prepared and used to localize the antigen in N. caninum tachyzoites and bradyzoites. By sodium dodecylsulfate-polyacrylamide gel electrophoresis and immunoblotting, antirecombinant Nc56 serum recognized a major 56-kDa protein and 2 minor (43 and 39 kDa) proteins of N. caninum tachyzoites. Antiserum to recombinant 56-kDa protein showed this antigen to be present in both N. caninum tachyzoites and bradyzoites/cysts as detected by immunofluorescence staining. Immunoelectron microscopy revealed the 56-kDa antigen to be present in the apical end of both tachyzoites and bradyzoites and possibly extracellularly secreted by tachyzoites.
Jenkins
Mark
M
Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, Agricultural Research Service, United States Department of Agriculture, Beltsville, Maryland 20705, USA. mjenkins@anri.barc.usda.gov
Soares
Rodrigo
R
Murphy
Charles
C
Hemphill
Andrew
A
O'Handley
Ryan
R
Dubey
J P
JP
D000818:Animals; D000953:Antigens, Protozoan / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D015152:Blotting, Northern / Q000662:veterinary; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis; D003048:Coccidiosis / Q000175:diagnosis / Q000662:veterinary; D018076:DNA, Complementary / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel / Q000662:veterinary; D005260:Female; D005455:Fluorescent Antibody Technique / Q000662:veterinary; D007106:Immune Sera / Q000276:immunology; D015151:Immunoblotting / Q000662:veterinary; D008018:Life Cycle Stages / Q000276:immunology; D051379:Mice; D016253:Microscopy, Immunoelectron / Q000662:veterinary; D018688:Neospora / Q000276:immunology* / Q000648:ultrastructure; D015800:Protozoan Proteins / Q000032:analysis* / Q000235:genetics / Q000276:immunology; D012333:RNA, Messenger / Q000737:chemistry; D011817:Rabbits
D000953:Antigens, Protozoan; D018076:DNA, Complementary; D007106:Immune Sera; D015800:Protozoan Proteins; D012333:RNA, Messenger