Phage display for identification of serum biomarkers of traumatic brain injury

Abstract

Background The extent and severity of traumatic brain injuries (TBIs) can be difficult to determine with current diagnostic methods. To address this, there has been increased interest in developing biomarkers to assist in the diagnosis, determination of injury severity, evaluation of recovery and therapeutic efficacy, and prediction of outcomes. Several promising serum TBI biomarkers have been identified using hypothesis-driven approaches, largely examining proteins that are abundant in neurons and non-neural cells in the CNS. New Method An unbiased approach, phage display, was used to identify serum TBI biomarkers. In this proof-of-concept study, mice received a TBI using the controlled cortical impact model of TBI (1 mm injury depth, 3.5 m/s velocity) and phage display was utilized to identify putative serum biomarkers at 6h postinjury. Results An engineered phage which preferentially bound to injured serum was sequenced to identify the 12-mer ‘recognizer’ peptide expressed on the coat protein. Following synthesis of the recognizer peptide, pull down, and mass spectrometry analysis, the target protein was identified as glial fibrillary acidic protein (GFAP). Comparison with Existing Methods and Conclusions GFAP has previously been identified as a promising TBI biomarker. The results provide proof of concept regarding the ability of phage display to identify TBI serum biomarkers. This methodology is currently being applied to serum biomarkers of mild TBI.

Peptide Phage Display: Molecular Principles and Biomedical Applications

“…PD technology was used to identify serum-associated traumatic brain biomarkers, such as glial fibrillary acidic protein, allowing the severity of brain injury damage to be detected and for recovery and therapeutic efficiency predictions to be made. 63 Additionally, PepC7 may act as highly selective peptide ligand that is specific for the brain vascular receptors in in vivo analysis and could be adapted for use in a drug delivery system in the brain. 64 A great deal of research in other medical and health fields have utilized PD technology.…”

Phage‐Enabled Nanomedicine: From Probes to Therapeutics in Precision Medicine

“…[138] Peptides that could preferentially bind the serum biomarkers for brain injury were selected using an M13 phage Ph.D.-12 phage library. The presence of injured brain serum biomarkers could then be determined through enzyme-linked immunosorbent assay (ELISA).…”

“…To further demonstrate the versatility of phage-inspired techniques for detecting biomarkers,Ghoshal et al were able to use phage display for the identification of serum biomarkers of traumatic brain injury. [138] Peptides that could preferentially bind the serum biomarkers for brain injury were selected using an M13 phage Ph.D.-12 phage library.The presence of injured brain serum biomarkers could then be determined through enzyme-linked immunosorbent assay (ELISA). Thet est compared non-injured brain serum to injured brain serum.…”

“…This protein has been previously shown to be ap romising biomarker of traumatic brain injury. [138] Thea nimal model used was C57BL/6 mice.T his technology has implications for helping to determine the extent and severity of traumatic brain injuries or distinguish them from more mild concussions.…”

Uncovering temporally sensitive targeting motifs for traumatic brain injury via phage display

“…Phage display, a powerful screening technique to uncover protein-protein interactions, has been applied to biomarker discovery in various cancers and more recently, neurological conditions such as Alzheimer's disease and stroke [15][16][17][18][19]. This technique utilizes libraries of biological motif-displaying bacteriophages that are then screened against target antigens.…”