Production of mouse monoclonal antibody against Streptococcus dysgalactiae GapC protein and mapping its conserved B-cell epitope

Res Vet Sci. 2015 Feb:98:39-41. doi: 10.1016/j.rvsc.2014.11.005. Epub 2014 Nov 11.

Abstract

Streptococcus dysgalactiae (S. dysgalactiae) GapC protein is a protective antigen that induces partial immunity against S. dysgalactiae infection in animals. To identify the conserved B-cell epitope of S. dysgalactiae GapC, a mouse monoclonal antibody 1E11 (mAb1E11) against GapC was generated and used to screen a phage-displayed 12-mer random peptide library (Ph.D.-12). Eleven positive clones recognized by mAb1E11 were identified, most of which matched the consensus motif TGFFAKK. Sequence of the motif exactly matched amino acids 97-103 of the S. dysgalactiae GapC. In addition, the epitope (97)TGFFAKK(103) showed high homology among different streptococcus species. Site-directed mutagenic analysis further confirmed that residues G98, F99, F100 and K103 formed the core of (97)TGFFAKK(103), and this core motif was the minimal determinant of the B-cell epitope recognized by the mAb1E11. Collectively, the identification of conserved B-cell epitope within S. dysgalactiae GapC highlights the possibility of developing the epitope-based vaccine.

Keywords: Epitope; GapC; Homology; Phage display; Streptococcus dysgalactiae.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Monoclonal / immunology*
  • Antibodies, Monoclonal / metabolism
  • Antigens, Bacterial / immunology*
  • Bacterial Proteins / immunology*
  • Epitopes, B-Lymphocyte / analysis
  • Epitopes, B-Lymphocyte / immunology*
  • Mice*
  • Molecular Sequence Data
  • Species Specificity
  • Streptococcal Infections / immunology
  • Streptococcal Infections / prevention & control
  • Streptococcal Infections / veterinary
  • Streptococcal Vaccines / immunology
  • Streptococcus / classification
  • Streptococcus / immunology*
  • Streptococcus Phages / immunology

Substances

  • Antibodies, Monoclonal
  • Antigens, Bacterial
  • Bacterial Proteins
  • Epitopes, B-Lymphocyte
  • GapC protein, Streptococcus
  • Streptococcal Vaccines