The science
In this video for Spear Bio, we explain how neutralizing antibodies block viruses from entering host cells, playing a crucial role in immune defense. Traditional testing methods require live virus cultures and specialized labs, limiting scalability and consistency. Spear Bio’s NAB-Sure™ test, powered by the SPEAR DNA proximity immunoassay platform, overcomes these challenges with a novel mechanism.
The test uses the SARS-CoV-2 S1 protein and the human ACE2 receptor, each tagged with unique DNA sequences. When they come into proximity, a DNA extension reaction occurs—unless neutralizing antibodies are present, which block the process and reduce the signal. This method delivers superior sensitivity compared to gold-standard cell-based assays, allowing analysis from small blood or dried blood spot samples. Compatible with qPCR instruments and liquid handling devices, NAB-Sure™ offers a scalable, reliable, and easy-to-use solution for monitoring immune response.
Learn more at spear.bio.
