A virus NT was performed in a biosafety level 3 laboratory to determine the titers. A SARS-CoV-2 enzyme-linked immunosorbent assay (ELISA) was designed to detect neutralizing antibodies in the serum, based on the binding affinity of SARS-CoV-2 viral protein 1viral protein 2 to antibodies. ELISA results viral protein 12, generated comparable neutralizing antibody titers. The results analyzed by spline regressiontwo-variable generalized additive model precisely reflected the real NT value. Our method can serve as a surrogate to quantify neutralizing antibody titer.

The invention provides a glycan-masking and/or glycan-unmasking hemagglutinin, wherein the glycosylation site(s) is added on globular headremoved on stem. The glycan-masking and/or glycan-unmasking hemagglutinin may induce neutralizing antibody against influenza virus,cross-reactive protection against different virus. The invention also provides a method for manufacturing these antigens.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infected human cell through ACE2. This study is developing a Pd nano-thin film electrode for electrochemical impedance spectroscopy. This invention can quantify neutralize antibody too. The detection platform can be used to screen 1 microliter anti-virus infection drug sample within 21 mins. Compare to SPR standard, our invention only needs 1/10000 concentration of ACE2reaction volume is ~1/30 than SPR. This invention can be adapted in detection of cancer markers,other emergency infection diseasestherapeutic drugs, too.