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Health9Bovine toll-like receptor 9: A comparative analysis of molecularstructure, function and expressionCorresponding AuthorGriebel, P.J.Vaccine and Infectious DiseaseOrganizationCollaboratorsBrownlie, R.Vaccine and Infectious DiseaseOrganizationManuja, A.Vaccine and Infectious DiseaseOrganizationNichani, A.Vaccine and Infectious DiseaseOrganizationMookherjee, N.University of British ColumbiaPopowych, Y.Vaccine and Infectious DiseaseOrganizationMutwiri, G.Vaccine and Infectious DiseaseOrganizationHecker, R.QIAGENVeterinary Immunology and Immunopathology (2005) Vol. 108 p. 11-16.Toll-like receptors (TLR), located on cell surfaces, are among the importantmolecules that alert the immune system to the presence of infection. Firstdiscovered about 10 years ago, 11 mammalian TLR have now been identified.Each is capable of recognizing unique molecular patterns associatedwith foreign organisms. Binding of these molecular sequences to the TLRinitiates the immune response through the release of cytokines and theactivation of immune cells. One of the TLR (TLR9) has been found to recognizeand bind short DNA segments referred to as CpG, commonly presentin bacteria and viruses. Numerous studies of TLR9-CpG binding in miceand humans have demonstrated that synthetic DNA fragments containingCpG can be used to stimulate the immune system in a variety of clinicalconditions. The objective of this study was to compare bovine TLR9 withthat found in mice and humans, to assess whether the beneficial effects ofTLR9-CpG binding in other species might be applied to cattle. Analysis ofthe bovine gene coding for TLR9 synthesis revealed close similarity to thatin humans. Binding to similar CpG-containing DNA fragments provokedoptimal immune cell activation in both species. The characteristics of bovineTLR9 had less in common with that found in mice.10Evaluation of the stability of Ostertagia ostertagi ELISA microtitreplates over time using cow milk samplesCorresponding AuthorSithole, F.University of AlbertaCollaboratorsDohoo, I.R.Atlantic Veterinary CollegeMarkham, F.Atlantic Veterinary CollegeSanchez, J.Atlantic Veterinary CollegeStryhn, H.Atlantic Veterinary CollegeKeefe, G.P.Atlantic Veterinary CollegeVeterinary Parasitology (2005) Vol. 133 p. 329-337.Ostertagia ostertagi is a stomach worm, a gastrointestinal parasite of cattle.Signs of infection include watery diarrhea, progressive weight loss, weakness,rough coat, and reduced appetite. Although fecal egg counts havebeen used to estimate worm burdens, this method has proven unreliable.A better measure is based on an enzyme-linked immunosorbent assay(ELISA) capable of detecting O. ostertagi antibodies in blood serum andmilk. However, one of the reagents commonly used in the ELISA procedure(bovine serum albumin: BSA) requires that the microtitre plates used in theassay must be kept frozen before use. This is an inconvenience when platesneed to be transported. Therefore, the objective of this study was to examinealternatives to the use of BSA in combination with either monoclonalor polyclonal anti-bovine antibody reagents. Two alternatives to BSA wereidentified which are stable for prolonged periods at ambient temperature.Use of one of these, in combination with the monoclonal anti-bovine antibodyreagent, was found to yield the best results.Health 67