FIG 1.

Impact of Spike protein cytoplasmic tail truncation on LV and VSV vectors. (A) Transduction of HeLa-ACE2 cells by equal volumes of unconcentrated vector supernatants of LV-GFP or VSV-Luc vectors, pseudotyped with full-length (S) or truncated (SΔ18) Spike proteins. Shown are means and standard deviations from 3 independent vector stocks. *, P < 0.05, unpaired t test, one-tail. (B) Spike protein incorporation into vector particles, analyzed by Western blotting using antibodies against the Spike S2 subunit and vector particle components p24 (LV) and M (VSV). Full-length Spike (S) and S2 subunit are indicated. (C) Genomic copy number for indicated vectors. Shown are means and standard deviations from 3 independent vector stocks.