TABLE 1.
Summary of IFA, Western blotting, ELISA, and HKU1 virus neutralization studies of mouse monoclonal antibodies to HKU1 S glycoprotein
| Antibody and assay | mHKUS-1 | mHKUS-2 | mHKUS-3 | mHKUS-4 | mHKUS-5 | mHKUS-6 |
|---|---|---|---|---|---|---|
| IFAa | ||||||
| HKU1 S | ++++ | + | ++ | ++++ | + | + |
| SARS S and infection | − | − | − | − | − | − |
| MHV S and infection | − | − | − | − | − | − |
| MERS S | − | − | − | − | − | − |
| BCoV infection | − | − | − | − | − | − |
| 229E infection | − | − | − | − | − | − |
| NL63 infection | − | − | − | − | − | − |
| Westernb | ||||||
| S14-294aa | ++++ | − | − | − | − | − |
| S295-755aa | + | − | − | − | − | − |
| ELISAc | ||||||
| HKU1 Secto | ++++ | ++++ | ++++ | ++++ | ++++ | ++++ |
| S14-755aa | ++++ | ++++ | ++++ | ++++ | ++++ | ++++ |
| S14-673aa | ++++ | ++++ | ++++ | ++++ | ++++ | ++++ |
| S14-534aa | ++++ | − | − | − | − | − |
| S14-443aa | ++++ | − | − | − | − | − |
| S14-294aa | ++++ | − | − | − | − | − |
| S295-755aa | + | ++++ | ++++ | ++++ | ++++ | ++++ |
| S295-673aa | + | ++++ | ++++ | ++++ | ++++ | ++++ |
| Neutralizationd | − | ++++ | ++++ | − | − | − |
For IFA, ++++ indicates that the percentage of virus antigen-positive cells was equal to or greater than 20%; +++, between 10 and 20%; ++, between 5 and 10%; +, between 1 and 5%; −, no positive cells. For HKU1 S, MHV S, SARS S, and MERS S infection, cells were transduced with plasmids encoding the membrane-anchored S proteins of these viruses. For SARS, MHV, BCoV, 229E, and NL63 infection, cells expressing the appropriate virus receptor proteins were infected with the indicated virus.
For Western blotting, ++++ indicates very strong signal; +++, strong signal; ++, weak signal; +, very weak signal; −, no signal.
For ELISA, ++++ indicates positive signal at 1:4,096 dilution of MAb or further; +++, positive signal at dilution between 1:256 and 1:4,096; ++, positive signal at dilution between 1:4 and 1:256; +, positive signal from undiluted or 1:4 dilution of hybridoma supernatant; −, no signal with undiluted hybridoma supernatant.
For neutralization, ++++ indicates greater than 100-fold inhibition of HKU1 virus infection, corresponding to the amount of viral RNA detected by real-time PCR in released virus at 48 hpi; +++, 10- to 100-fold inhibition; ++, 5- to 10-fold inhibition; +, 2- to 5-fold inhibition; −, no inhibition.