Use of synthetic peptides to map sequential epitopes recognized by monoclonal antibodies on the bovine leukemia virus external glycoprotein

Abstract

Six sequential epitopes (A, B, B', D, D', E) were previously defined on the bovine leukemia virus (BLV) envelope glycoprotein gp51 by their reactivity with monoclonal antibodies. A panel of synthetic peptides covering almost the entire sequence of gp51 was tested in enzyme-linked immunosorbent assays in order to localize these epitopes. E was shown to be included in peptide 142-161 (MCF4), B and B' in peptide 195-205, D and D' in peptide 218-237 (MCF6), and A in peptide 249-268 (MCF7). These results extend and confirm previous observations suggesting that the sequential epitopes recognized by our battery of monoclonal antibodies are located in the carboxylic half of BLV gp51.

Identification of functional sites on bovine leukemia virus envelope glycoproteins using structural and immunological data

“…It is quite likely that inhibition of a function depending on oligomerization plays a role in infectivity. Curiously enough, it has been demonstrated that one overlapping peptide (peptide 142 -161) contains the sequential site E, defined by a non-neutralizing mAb [37]. However, this site was previously suspected to be important for oligomerization since mAbE presents the external glycoprotein gp5 1 in a quasi-native configuration, as obtained with the total gp51-gp30 complex [38].…”

Iodoacetamide treatment of bovine leukemia virus glycoprotein gp51 enhances the Western blotting reactivity of anti‐peptide antibodies

“…ELISA antibody titers obtained with the 27 peptides mentioned above were reported in previous papers [1,2] and some are recalled in Table I for a few illustrative purposes. From Table I and Fig.…”

“…Previous studies [1,2] and more recent observations with new anti-peptide antibody systems indicated that only two regions of gp51 are well recognized by rabbit anti-peptide sera in classical WB. The first region is the carboxylic end of the protein (peptide 255-268) [1]; the second (142-161) corresponds to a putative hinge between the NH2 and COOH moieties of gp51 [2].…”

“…The first region is the carboxylic end of the protein (peptide 255-268) [1]; the second (142-161) corresponds to a putative hinge between the NH2 and COOH moieties of gp51 [2]. Both regions seem to be particularly accessible even on the native envelope protein.…”

Analysis by Sodium Dodecyl Sulfate Polyacrylamide gel Electrophoresis and Western Blot of Nonspecific and Specific Viral Proteins Frequently Detected in Different Antigen Preparations of Bovine Leukemia Virus

“…The localization of the other main BLV protein, the envelope glycoprotein gp51, is more difficult because it undergoes denaturing and thus loses its natural conformation and presentation of the epitopes before and during the electrophoresis process. 1,6,10,18,28 Nevertheless, a number of bands in the range of 60-80 kD have been observed. Gp51 has been detected by WB in the 50-60 kD range in 6 different antigen preparations using an anti-gp51 monoclonal antibody.…”