Novel Chemokine-Based Immunotoxins for Potent and Selective Targeting of Cytomegalovirus Infected Cells

Table 2

Cell killing activity of the FTPs.

	US28 exp. cells		CX3CR1 exp. cells		Selectivity
	log IC50  ± SD	IC50 [nM]	log IC50  ± SD	IC50 [nM]	US28 versus CX3CR1
CX3CL1-FTP	−10.6 ± 0.52	0.026	−9.6 ± 0.45	0.25	10
K14E-FTP	−10.5 ± 0.25	0.029	−8.0 ± 0.22	11	380
F49A-FTP	−10.6 ± 0.24	0.028	−7.8 ± 0.15	14	513
F49L-FTP	−11.1 ± 0.41	0.008	−8.7 ± 0.24	2.2	275
F49E-FTP	−9.6 ± 0.47	0.27	−7.5 ± 0.30	32	117
F49A-FTP 2	−10.3 ± 0.08	0.051	−7.8 ± 0.30	16	309
F49A-FTP 3	−9.8 ± 0.16	0.15	−7.6 ± 0.20	25	162
F49A-FTP 4	−9.8 ± 0.06	0.17	−7.6 ± 0.30	25	151
F49A-FTP 5	n.a.		n.a.		—
F49A-FTP 6	−9.5 ± 0.20	0.34	−7.5 ± 0.10	32	93
F49A-FTP 7	−11.3 ± 0.24	0.005	−9.5 ± 0.49	0.35	66

log IC50 values are estimated from a partial curve.
IC50 value estimated from 3–6 experiments.