TOI-IGRA: A Fingertip Blood Biosensing Technology for Decentralized Quantification of Pathogen-Specific T-Cell...

Area of Science:

• Immunology
• Diagnostic assay development
• Point-of-care testing

Background:

• T-cell immune responses are crucial for adaptive immunity and tuberculosis (TB) diagnosis.
• Conventional Interferon-γ Release Assays (IGRAs) require significant venous blood volumes and lengthy processing, limiting their use in resource-limited settings.
• There is a need for rapid, minimally invasive, and decentralized T-cell functional assays.

Purpose of the Study:

• To develop and validate a novel fingertip blood-based T-cell functional assay, TOI-IGRA, as an alternative to conventional IGRA.
• To assess the diagnostic performance of TOI-IGRA for TB.
• To explore the versatility of the TOI-IGRA platform for other pathogens and antibody detection.

Main Methods:

• Development of the Tip Optofluidic Immunoassay (TOI) platform for T-cell functional assays.
• Utilizing minimal capillary blood (15-25 μL) for TOI-IGRA.
• Clinical validation in TB patients comparing TOI-IGRA with standard IGRA.

Main Results:

• Fingertip blood yielded comparable T-cell functional results to venous blood.
• TOI-IGRA demonstrated diagnostic performance equivalent to standard IGRA in TB patients.
• The platform showed potential for assessing T-cell responses to SARS-CoV-2 and concurrent antibody detection.

Conclusions:

• TOI-IGRA provides a rapid, minimally invasive, and efficient method for T-cell functional assessment using fingertip blood.
• This assay is suitable for decentralized diagnostics, immune surveillance, and personalized vaccine monitoring.
• The TOI-IGRA platform offers a versatile solution for various diagnostic and monitoring applications.