title: Rapid and sensitive detection of cytokines using functionalized gold nanoparticle-based immuno-PCR, comparison with immuno-PCR and ELISA.
abstract: Reliable and simple methods are required for detection of low concentrations of cytokines and some other proteins in complex biological fluids. This is especially important when monitoring the immune responses under various physiological and pathophysiological conditions in vivo or following production of these compounds in in vitro systems. Cytokines and other immunologically active molecules are being predominantly detected by enzyme-linked immunosorbent assays (ELISA) and newly also by immuno-polymerase chain reactions (iPCR). New simplified variants of iPCR have recently been described where antibodies are connected with multiple DNA templates through gold nanoparticles (Au-NPs) to form a new class of detection reagents. In this study we compared functionalized Au-NP-based iPCR (Nano-iPCR) with standard ELISA and iPCR for the detection of interleukin (IL)-3 and stem cell factor (SCF). The same immunoreagents (IL-3- and SCF-specific polyclonal antibodies and their biotinylated forms) were used throughout the assays. The obtained data indicate that both Nano-iPCR and iPCR are superior in sensitivity and detection range than ELISA. Furthermore, Nano-iPCR is easier to perform than the other two methods. Nano-iPCR was used for monitoring changes in concentration of free SCF during growth of mast cells in SCF-conditioned media. The results show that growing cultures gradually reduce the amount of SCF in supernatant to 25% after 5 days. The combined data indicate that Nano-iPCR assays may be preferable for rapid detection of low concentrations of cytokines in complex biological fluids.
authors.affiliation: Laboratory of Signal Transduction, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, CZ-14220 Prague 4, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Potůčková
authors.forename: Filip
authors.initials: F
authors.lastname: Franko
authors.forename: Monika
authors.initials: M
authors.lastname: Bambousková
authors.forename: Petr
authors.initials: P
authors.lastname: Dráber
mesh_terms: D000818:Animals; D000906:Antibodies; D002478:Cells, Cultured; D016207:Cytokines / Q000032:analysis* / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D006046:Gold; D007118:Immunoassay / Q000379:methods* / Q000706:statistics & numerical data; D007202:Indicators and Reagents; D007377:Interleukin-3 / Q000032:analysis / Q000276:immunology; D008407:Mast Cells / Q000276:immunology; D053768:Metal Nanoparticles; D051379:Mice; D036103:Nanotechnology; D016133:Polymerase Chain Reaction / Q000379:methods* / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity; D019089:Stem Cell Factor / Q000032:analysis / Q000276:immunology
chemical_list: D000906:Antibodies; D016207:Cytokines; D007202:Indicators and Reagents; D007377:Interleukin-3; D019089:Stem Cell Factor; D006046:Gold