Alterations in Humoral Immune Response to Bovine Leukaemia Virus Antigens in Cattle with Lymphoma

Abstract

SUMMARYSera collected from cattle with enzootic bovine lymphoma (EBL) were compared to sera from clinically normal bovine leukaemia virus (BLV)-infected cattle for immunoglobulin concentration and for antibodies detecting BLV proteins tested using three different viral isolates. Monoclonal antibodies to bovine immunoglobulin isotypes were used in Western blot analysis to identify isotype reactivity to specific viral antigens. IgG titres to BLV were determined by ELISA. Serum immunoglobulin (G1, G2 and M) concentrations were assessed by radial immunodiffusion. Although EBL was associated with reduced total immunoglobulin production, sera from cattle with EBL had significantly (P< 0-001) higher specific IgG titres and produced antibodies against a greater and more varied number of BLV proteins than did sera from clinically normal BLV-infected cattle. Variations were consistent within groups of cattle and did not depend on the viral isolate used.

Comparison of Agar Gel Immunodiffusion Test, Enzyme‐linked Immunosorbent Assay and Western Blotting for the Detection of BLV Antibodies

“…This observation is relevant, stressing Thc WB dcscribed in this work showed a high sensitivity. In accordancc with Hunger et al (1994), Heeney et al (1988), Ristau et al (1988) and Walker et al (1987) the p24 protcin was the most important BLV-antigen concerning sensitivity and specificity of the assay. The WB has the advantages of easy proof of specificity (appearance of the p24-band).…”

Expression of bovine leukemia virus protein p24 in Escherichia coli and its use in the immunoblotting assay.

“…However, the use of an appropriate BLV antigen seems to be crucial for the usefulness of this method [14]. The discrepancy between the results obtained in the conventional serological and in the Western blot assays regarding the gp51-binding antibodies has been reported previously [15,16]. Although in sera from the infected animals the reaction with gag-related protein p24 is very clear, the reaction against gp51 may be weaker or absent.…”

Enzyme-Linked Immunosorbent Assays Using the Recombinant gp51 and p24 of Bovine Leukemia Virus for Immunodetection of the Disease

“…Other authors reports that high sensitivity tests are able to detect anti-p24 antibodies before the appearance of anti-gp51 antibodies; and the anti-p24 antibodies could be an equal or greater degree than anti-gp51 [3] [10]. The immunoglobulin isotype in the immune response varies according to the stages of LEB disease, in asymptomatic animals IgM and IgG1 anti p24 and gp51were detected, whereas the detection of IgA occurs in animals with lymphoma [11].…”