J.M. Obliosca, D. Patel, Y. Xu, C. Tison
Luna Innovations Incorporated,
Keywords: In vitro diagnostic assay, multiplex detection, surface plasmon resonance imaging, atopic dermatitis, cytokines, patient serum, limited sample volume
Summary:Atopic dermatitis (AD) is a recurring inflammatory skin condition that affects 30% of children and 10% of adults in both developed and developing countries. AD, which affects more than 30 million people in the US, is characterized by dry skin, intense pruritis, and poses negative impacts on the quality of life of children and their families. Therapeutic interventions such as corticosteroids, UV therapy and the immunosuppressant macrolides require comprehensive understanding of cytokines that are secreted by the immune cells involved in the complex immunologic pathways of AD. Strategies that allow rapid and precise monitoring of immunologic status associated with disease prevention, remission, progression and treatment are therefore highly desired. Current assays for AD including ELISA, ELISpot, real-time PCR and bead-based techniques are often laborious, expensive, have a bias in enzymatic labeling, and frequently require a relatively large sample volume as each biomarker of interest is tested individually. Additionally, the availability of biofluids collected from pediatric and immune-suppressed individuals are often inadequate for several tests needed to yield conclusive findings. This lack of rapid, multiplex, low volume assays makes immune monitoring for clinical decision-making (especially on critically ill patients) impractical. Without such assays, immune monitoring is even virtually impossible for infants and neonates. Luna has developed a nanoSPRi (nanoenhanced Surface Plasmon Resonance imaging)-based immunosensing platform (termed nanoSPRiSA) to realize multiplex identification of a number of cytokines from significantly reduced sample volume necessary to assess signaling pathways and disease progression state of AD. Luna’s nanoSPRiSA includes a pre-assembled sensing chip with all necessary surface activation reagents and protocols for detecting biomarkers for AD serum cytokines. The system uses surface plasmon resonance imaging for the rapid detection of AD serum cytokines with multiplex screening of up to 400 samples spots of a panel of biomarkers using limited amount (40 uL) of AD patients’ serum samples. The platform consists of a proprietary blocking and chip activation reagent kit that nearly eliminates non-specific binding from biofluid samples and a nanoenhancer to enable ultrasensitive detection at pg/mL levels with a large linear range. The system allows monitoring of real-time binding kinetics and simultaneous detection of a panel of biomarkers without the use of enzymes and fluorescent dye labels. These highly notable features of Luna’s sparing assay allow elimination of drawbacks typically encountered on ELISA, ELISpot, PCR and bead-based techniques. This diagnostic capability being developed by Luna is a platform technology, and upon successful implementation for AD, could be reconfigured for the study of a wide variety of pathologies/diseases and other sample matrices.