Format

Send to

Choose Destination
J Biotechnol. 2017 Sep 10;257:118-121. doi: 10.1016/j.jbiotec.2016.12.010. Epub 2016 Dec 15.

Immunomagnetic separation of human myeloperoxidase using an antibody-mimicking peptide identified by phage display.

Author information

1
Department of Bionanotechnology, Graduate School, Hanyang University-ERICA, Ansan 15588, Republic of Korea.
2
Department of Bionanotechnology, Graduate School, Hanyang University-ERICA, Ansan 15588, Republic of Korea. Electronic address: eklee@hanyang.ac.kr.

Abstract

Phage display biopanning is a powerful in vitro selection process for screening and identifying peptides that bind to a target protein of interest. With the aim of replacing antibodies in immuno-diagnostic applications, we identified peptides whose binding characteristics mimicked those of anti-human myeloperoxidase (hMPO), a biomarker for acute cardiac diseases. Based on ELISA results from four phage clones, we selected and chemically synthesized a 12-mer peptide (SYIEPPERHRHR). Quartz crystal microbalance and surface plasmon resonance analyses revealed that the molar binding equilibrium ratio of the synthesized peptide was 0.023, approximately 43-fold lower than that of the anti-hMPO antibody. The dissociation constant (Kd) was 57nM, which was comparable to that of the native antibody (83nM). Next, we biotinylated the peptide at its N-terminus and attached the biotinylated peptide to the surface of streptavidin-coated magnetic particles to assess its ability to selectively capture hMPO. The binding equilibrium data were similar to the previous analyses; specifically, around 0.021mol peptide bound to 1mol of hMPO. Antigen capture was found to be selective and to be relatively little influenced by the presence of human serum albumin (HSA), an abundant constituent of serum. Our work demonstrates the potential of immunomagnetic isolation to achieve selective capture of a low-concentration antigen from complex solutions such as serum.

KEYWORDS:

Antibody-mimicking peptide; Binding affinity; Human myeloperoxidase; Immuno-binding; Magnetic particle; Phage display

PMID:
27989733
DOI:
10.1016/j.jbiotec.2016.12.010
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center