covid-19 ASSAYS and studies

– Efficacy assay using either Vero E6 or Calu-3 cells

– Looks at 50% effective concentration (EC₅₀) of the drug against SARS-CoV-2. 

SARS-CoV-2 48hr neutralization assays for antibodies to determine reduction of plaques and viral measurements.

PRNT

– Plaques are visualized and counted using an ELISPOT instrument

– Plaque counts are fitted to a dose-response curve and plaque reduction neutralization test titers (PRNT) expressed in terms of conventional 50% PRNT end-point titers.

ELISA

– For each well, the inhibition of virus by neutralizing antibodies is calculated as the percentage of reduction of the absorbance value in respect of the virus control

– The neutralizing antibody titer is defined as the reciprocal dilution that caused 50% reduction of the absorbance value of the virus control (50% A450 reduction)

– Clinical signs such as body weight loss, although no mortality

– Viral load in nasal washes and blood

– Routes of dosage admin include intranasal, inhaled (inhalation), and intraperitoneal

-Virus detection in various tissues

References for this model: iitri.org/covid-19-syrian-hamster-model/

– Favorable model for looking at effects solely in upper respiratory tract

– Infection model only, no clinical signs

– Viral load and shedding in nasal washes

– Routes of dosage admin include intranasal, intraperitoneal, inhaled (inhalation), and intravenous 

References for this model: IITRI ferret studies

– K18-hACE2 transgenic mouse model

Clinical signs such as body weight loss, mortality

– Viral load in nasal washes

Dose range-finding data for the hACE2- transgenic mouse model