Internal image rabbit anti-idiotypic antibody detects sheep antibodies to the bluetongue virus core protein VP7.
BACKGROUND
Rabbit polyclonal anti-idiotypic antibodies (anti-Id) were generated against three murine monoclonal antibodies (MAbs) specific for the group-specific antigen VP7 of bluetongue virus (BTV) by the sequential immunization method. It was demonstrated by serological tests that part of the anti-Id possesses the characteristics of internal image anti-Id. By affinity purification against the individual MAbs, the internal image anti-Id, designated RAb2-A, was isolated and identified as specific for the MAb, M1875.


OBJECTIVE
To examine the ability of RAb2-A to detect sheep anti-VP7 antibodies by recognition of the common idiotype (Idx).


METHODS
Affinity-purified RAb2-A IgG, along with VP7, was applied on the solid-phase of ELISA plate and the membrane for Western blot analysis to detect anti-VP7 antibodies from sheep that were immunized with VP7 or were experimentally infected with BTV. An inhibition ELISA was employed to determine whether sheep anti-VP7 and M1875 recognize the same or similar epitope(s).


RESULTS
RAb2-A recognised the Idx on anti-VP7 antibodies from sheep that were either immunized with VP7 or experimentally infected with BTV. Specificity of the reaction was confirmed by the observation that RAb2-A did not react with normal sheep serum or sheep antibodies against epizootic haemorrhagic disease of deer virus, a bluetongue-related disease virus in the Orbivirus genus.


CONCLUSIONS
The ability of RAb2-A to detect anti-VP7 antibodies through recognition of the Idx suggests that RAb2-A can be used as a probe to detect anti-BTV antibodies.
Lin
M
M
Virology Section, Animal Diseases Research Institute, Nepean, Ontario, Canada.
Zhou
E M
EM
D000818:Animals; D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral / Q000032:analysis*; D000956:Antigens, Viral / Q000276:immunology*; D001820:Bluetongue virus / Q000276:immunology*; D051379:Mice; D011817:Rabbits; D012756:Sheep; D014758:Viral Core Proteins / Q000276:immunology*
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D000956:Antigens, Viral; D014758:Viral Core Proteins; C066862:VP7 protein, orbivirus