Abstract
Purpose: :
Measurement of cytokine or antibody concentrations in the aqueous humor is of interest in a variety of eye diseases (e.g. corneal graft rejection, uveitis), but is limited by the small volume achievable. Therefore, the aim was to establish a new method for detecting up to more than 20 clinically relevant cytokines or antibodies in a volume of less than 100 ml.
Methods: :
We used a new 3 D protein biochip platform based on microstructured surface-attached polymer networks. In contrast to conventional multiparametric immunoassays, the sensitivity could be enhanced with this non-competitive ELISA on-chip technology. In the first run we tested the detection of 20 cytokines in parallel. The sensitivity and specificity were estimated in aqueous humor.
Results: :
Seventeen of the 20 cytokines (IL-2, -4, -6, -8, -12, -13, -17, -23, IFN gamma, TNF alpha, TGF beta 2, FasL, CCL2, Angiopoietin-1, VEGF, GM-CSF, PDGF) were detectable simultaneously for a broad range of relevant concentrations in a proportional manner. The results obtained from salt solution and aqueous humor were comparable respectively. There was no cross-reaction and no inhibition between the different antibodies and cytokines used.
Conclusions: :
Detection of 20 or more cytokines in a volume of less than 65 ml of aqueous humor is possible with this novel 3 D chip technology, which is a great advantage in simultaneous multiparametric screening of aqueous humor. In addition to that, the biochip gives information about the composition of the cytokine content in the aqueous humor depending on different eye diseases.
Keywords: clinical research methodology • cytokines/chemokines • anterior chamber