Clinically related protein-peptide interactions monitored in real time on novel peptide chips by surface plasmon resonance imaging.
BACKGROUND
Developing rapid, high-throughput assays for detecting and characterizing protein-protein interactions is a great challenge in the postgenomic era. We have developed a new method that allows parallel analysis of multiple analytes in biological fluids and is suitable for biological and medical studies.


METHODS
This technology for studying peptide-antibody interactions is based on polypyrrole-peptide chips and surface plasmon resonance imaging (SPRi). We generated a chip bearing a large panel of peptide probes by successive electro-directed copolymerizations of pyrrole-peptide conjugates on a gold surface.


RESULTS
We provide evidence that (a) the signal produced by antibody binding is highly specific; (b) the detected signal specifically reflects the antibody concentration of the tested solution in a dose-dependent manner; (c) this technique is appropriate for analyzing complex media such as undiluted sera, a novelty with respect to previous techniques; and (d) correlation between classic ELISA results and the SPRi signal is good (P = 0.008). We also validated this system in a medical model by detecting anti-hepatitis C antibodies in patient-derived sera.


CONCLUSIONS
Because of its characteristics (easy preparation of the peptide chip; high-throughput, label-free, real-time detection; high specificity; and low background), this technology is suitable for screening biological samples and for large-scale studies.
Cherif
Boutheina
B
Laboratoire d'Immunochimie, Commissariat à L'Energie Atomique-Grenoble/Départment Réponse et Dynamique Cellulaire, Institut National de la Santé et de la Recherche Médicale U548, Université J. Fourier, Grenoble, France.
Roget
André
A
Villiers
Christian L
CL
Calemczuk
Roberto
R
Leroy
Vincent
V
Marche
Patrice N
PN
Livache
Thierry
T
Villiers
Marie-Bernadette
MB
D001666:Binding Sites, Antibody; D002624:Chemistry, Clinical; D006046:Gold; D016174:Hepacivirus / Q000276:immunology; D018937:Hepatitis C Antibodies / Q000737:chemistry*; D006801:Humans; D010455:Peptides / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D040081:Protein Array Analysis / Q000295:instrumentation / Q000379:methods*; D025941:Protein Interaction Mapping; D011758:Pyrroles / Q000737:chemistry*; D011994:Recombinant Proteins / Q000737:chemistry; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000737:chemistry; D020349:Surface Plasmon Resonance
D018937:Hepatitis C Antibodies; D010455:Peptides; D011108:Polymers; D011758:Pyrroles; D011994:Recombinant Proteins; D012710:Serum Albumin, Bovine; C067635:polypyrrole; D006046:Gold