Titration of Human Coronaviruses, HCoV-229E and HCoV-OC43, by an Indirect Immunoperoxidase Assay
Calculation of infectious viral titers represents a basic and essential experimental approach for virologists. Classical plaque assays cannot be used for viruses that do not cause significant cytopathic effects, which is the case for strains 229E and OC43 of human coronavirus (HCoV). An alternative indirect immunoperoxidase assay (IPA) is herein described for the detection and titration of these viruses. Susceptible cells are inoculated with serial logarithmic dilutions of samples in a 96-well plate. After viral growth, viral detection by IPA yields the infectious virus titer, expressed as “tissue culture infectious dose” (TCID50). This represents the dilution of a virus-containing sample at which half of a series of laboratory wells contain replicating virus. This technique is a reliable method for the titration of HCoV in biological samples (cells, tissues, or fluids).
Key Wordshuman coronavirus HCoV-229E HCoV-OC43 cell and tissue samples titration immunoperoxidase assay TCID50
This work was supported mainly by grant MT-9203 from the Canadian Institutes of Health Research (Institute of Infection and Immunity).
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