TABLE 2.

Cross-competition of Ad serotypes by purified knob proteins^a

Sero- type	Inhibitionb by:
	A (F12K)	B (F3K)	C (F2K)	D (F9K)	E (F4K)	F
						F41LK	F41SK
Ad12	+++	−	+++	+++	+++	+++	−
Ad3	−	+++	−	−	−	−	−
Ad2	+++	−	+++	+++	+++	+++	−
Ad9	++	−	++	++	++	++	−
Ad4	+++	−	+++	+++	+++	+++	−
Ad41	+++	−	+++	+++	+++	+++	−

^aApproximately 10⁶ A549 cells (human lung carcinoma cells) were preincubated for 1 h in 250 μl of PBS plus 2 μg of purified fiber knob protein per ml at 37°C. The cells were chilled for 10 min, and ³H-labeled serotypes were added and incubated for 1 h at 4°C. The cells were washed twice. The pellet was taken up in 100 μl of PBS, added to scintillation cocktail, and counted directly. 

^b+++, >95% inhibition; ++, 40 to 60% inhibition; −, no inhibition.