Cloning antifungal single chain fragment variable antibodies by phage display and competitive panning elution.

Department of Biochemistry, Niigata University of Pharmacy and Applied Life Sciences, Japan.
Analytical Biochemistry (Impact Factor: 2.58). 09/2009; 395(1):16-24. DOI: 10.1016/j.ab.2009.08.003
Source: PubMed

ABSTRACT Phage display and two competitive panning elution conditions were used to isolate Candida-specific single chain fragment variable (scFv) antibodies. An scFv phage library constructed from splenic lymphocytes of mice immunized by idiotypic vaccination with an HM-1 killer toxin (HM-1)-neutralizing monoclonal antibody (nmAb-KT) was used for panning against Candidaalbicans membrane fraction (CaMF). Key steps were specific elution conditions to separately release the bound phages with original antigen HM-1+HM-1 peptide 6 and CaMF. The positive phages were screened by using enzyme-linked immunosorbent assay, and after nucleotide sequencing, clone expression, and purification, clone scFv-C1 was selected for detailed characterization. The scFv-C1 showed IC(50) values for cell growth against various Candida species and Saccharomyces cerevisiae as 2.40 to 6.40microM and 2.20microM, respectively. By using surface plasmon resonance analysis, the scFv-C1 had a K(d) value of 3.09x10(-11)M to nmAb-KT, indicating a 260-fold higher affinity than for HM-1. These results showed the generated scFv-C1 mimicking HM-1-binding affinity to nmAb-KT and in vitro antifungal activity. We believe that the effectiveness of the competitive panning elution method and antigen-specific recombinant scFv antibodies obtained in this study are excellent candidates for antimycotic drugs.

1 Bookmark
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We reported previously competitive panning elution with PBS (pH 7.0) that contains HM-1 killer toxin (HM-1) and Candida albicans membrane fraction (CaMF) to release phages bound with CaMF as an antigen. Here, as an alternative strategy, we isolated high-binding affinity recombinant single-chain fragment variables (scFvs) with in vitro anti-fungal activity from an scFv phage library. The competitive panning elution contained acidic, neutral and basic pH buffers with original antigen HM-1 or HM-1 peptide 6 used to release phages bound with HM-1-neutralizing monoclonal antibody (nmAb-KT). For neutral pH eluted conditions, 87.5% of clones showed high-binding affinity against nmAb-KT by using ELISA, but was 16% and 26% for acidic and basic eluted conditions, respectively. After nucleotide sequencing, we obtained seven different anti-idiotypic antibodies from the different selection procedures. The clone expression and purification by using a HisTrap HP column, showed that clones scFv S3, S4 and S7 had in vitro antifungal activity against Saccharomyces cerevisiae, Candida albicans. The purified scFvs showed strong binding affinity with nmAb-KT by using ELISA. These results showed that changing the buffer pH with competing elements plays important role in elution of bound phages to targeted antigen and also in identification of positive scFv phages.
    Journal of Biochemistry 05/2010; 147(5):723-33. · 3.07 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Aspergillus fumigatus causes the highly lethal form of invasive aspergillosis (IA). In the present study to develop a novel anti-fungal drug for protection against invasive disease, we identified a single chain fragment variable (scFv) antibody (scFv AF1) by panning against A. fumigatus membrane fraction (AMF) or HM-1 killer toxin (HM-1) neutralizing monoclonal antibody (nmAb-KT) as antigen. The key step was elution of bound phages with phosphate buffered saline (PBS) at pH 7.0 containing AMF. The specificity of soluble scFv AF1 antibody to antigens was verified by ELISA, which specifically binds to both AMF and nmAb-KT. After nucleotide sequencing, clone expression and purification by HisTrap HP affinity column, scFv AF1 showed in vitro anti-fungal activity against A. fumigatus. By SPR analysis it showed high binding affinity to nmAb-KT (K(d)=5.22×10(-11) M). The method used to isolate scFv AF1 was a new method and we believe that it will be applicable to isolate the specific scFv against any kind of membrane protein of yeast or fungus.
    Journal of immunological methods 01/2011; 366(1-2):60-8. · 2.35 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Phage display is a powerful technique in medical and health biotechnology. This technology has led to formation of antibody libraries and has provided techniques for fast and efficient search of these libraries. The phage display technique has been used in studying the protein-protein or protein-ligand interactions, constructing of the antibody and antibody fragments and improving the affinity of proteins to receptors. Recently phage display has been widely used to study immunization process, develop novel vaccines and investigate allergen-antibody interactions. This technology can provide new tools for protection against viral, fungal and bacterial infections. It may become a valuable tool in cancer therapies, abuse and allergies treatment. This review presents the recent advancements in diagnostic and therapeutic applications of phage display. In particular the applicability of this technology to study the immunization process, construction of new vaccines and development of safer and more efficient delivery strategies has been described.
    Human vaccines & immunotherapeutics. 12/2012; 8(12).


Available from
May 26, 2014