A Streamlined, Label-Free Real-Time 50% Tissue Culture Infectious Dose (TCID50) Assay using Impedance for Automated...

Area of Science:

• Virology
• Biotechnology
• Cell Biology

Background:

• Traditional viral titer assays like plaque and TCID50 are time-consuming and subjective.
• These methods often require staining or labeling, introducing variability and limiting real-time analysis.
• Capturing dynamic virus-cell interactions is challenging with static, endpoint measurements.

Purpose of the Study:

• To develop and validate a streamlined, objective, and real-time method for measuring viral titer (TCID50).
• To overcome the limitations of traditional assays by utilizing impedance-based technology.
• To enable noninvasive monitoring of cytopathic effects (CPE) without the need for labels.

Main Methods:

• Developed a TCID50 assay using impedance-based technology for real-time CPE measurement.
• Validated the assay with GFP-labeled adenovirus (Adv-GFP) in HEK293A cells and influenza A virus (IAV) in MDCK cells.
• Employed automated software for TCID50 calculation using the Reed-Muench formula.

Main Results:

• The impedance-TCID50 assay provided objective and noninvasive real-time measurements of CPE.
• TCID50 values for influenza A virus correlated well with conventional crystal violet staining methods.
• The assay demonstrated efficiency and precision in virus quantification across different cell models.

Conclusions:

• Impedance-based technology offers a streamlined and efficient alternative for viral titer measurement.
• This novel assay enhances insights into viral dynamics and supports advanced virological research.
• The technology has potential for expanded clinical applications in diagnostics and drug development.