TABLE 1.

Quantitative internalization assay results for VZV gE and gI

Incubation time (min)a	gI aloneb				gI with gEc				gE aloned				gE with gIe
	Radioactivity		Internalization		Radioactivity		Internalization		Radioactivity		Internalization		Radioactivity		Internalization
	cpmf	Corrected cpmg	%h	% (mean ± SD)i	cpm	Corrected cpm	%	% (mean ± SD)	cpm	Corrected cpm	%	% (mean ± SD)	cpm	Corrected cpm	%	% (mean ± SD)
0 (without trypsin)	35,235	33,272	100	100	34,936	33,655	100	100	34,942	33,607	100	100	27,026	25,912	100	100
0 (with trypsin)	1,963	0	0	0	1,281	0	0	0	1,335	0	0	0	1,114	0	0	0
15	16,206	14,243	42.8	43.3  ±  0.8	20,874	19,593	58.2	58.4  ±  0.9	11,686	10,351	30.8	30.7  ±  0.5	15,236	14,122	54.5	55.2  ±  0.9
30	17,344	15,381	46.2	46.3  ±  0.7	21,656	20,375	60.5	60.5  ±  0.5	11,961	10,626	31.6	31.9  ±  1	15,806	14,692	56.7	56.8  ±  0.6
45	17,580	15,617	46.9	47.3  ±  0.7	22,019	20,738	61.6	61.8  ±  0.9	12,197	10,862	32.3	32.5  ±  0.5	16,013	14,899	57.5	57.3  ±  0.8
60	17,644	15,681	47.1	47.4  ±  0.6	21,786	20,505	60.9	61.1  ±  0.8	11,780	10,445	32.1	32.2  ±  0.5	15,858	14,744	56.9	56.9  ±  0.9

^aThe cells were incubated for the time indicated at 37°C following incubation with antibody during the endocytosis assay. The cells were either left untreated or were treated with trypsin, which removes all the surface proteins, before (0 min) or after the incubation times indicated at 37°C. The proteins which were left after trypsin treatment represented the internalized protein. 

^bThe VZV gI gene was transfected into HeLa cells, and the gI protein was precipitated with anti-gI MAb 6B5. 

^cThe VZV gI gene and the VZV gE gene were transfected into HeLa cells, and the gE:gI complex was precipitated with MAb 6B5. 

^dThe VZV gE gene was transfected into HeLa cells, and the gE protein was precipitated with anti-gE MAb 3B3. 

^eThe VZV gE gene and the VZV gI gene were transfected into HeLa cells, and the gE:gI complex was precipitated with MAb 3B3. 

^fThe radioactivity of each protein in counts per minute was determined with an Instantimager. 

^gThe radioactivity of each protein was corrected by subtracting the background radioactivity measured in the control sample (incubation time, 0 min; with trypsin). 

^hThe percentage of protein internalized was determined by dividing the corrected counts per minute at each time point by the corrected counts per minute of the total protein present on the surface at the beginning of the assay (time, 0 min; without trypsin), and multiplying this value by 100. 

ⁱThese values represent data collected for this experiment and three additional independent experiments conducted in a similar manner, as described in Materials and Methods.