Figure 1
a: FACS analysis. FA8H1 binding in HCC cell lines is shown as a bold line. Background staining (shown in dashed line) was obtained using sonicated precipitation of E. coli TOP10F′ as a negative control. b: Specific binding assay of 131I-FA8H1 in five HCC cell lines. Cells were suspended in 0.2% BSA-PBS and split into two groups. One group was incubated with 131I-FA8H1 (designated as TB, total binding) at a final concentration of 10 μg/ml for 1 h in a 37 °C water-bath. Cells were washed twice and spun at 3,000 rpm for 10 min, then were read with a gamma reader and shown as counts per minute (CPM). Another group was incubated with the presence of a 200-fold molar excess of 131I-labelled unlabeled cFab to determine the nonspecific binding as the blank (NSB, nonspecific binding). The various specific bindings of 131I-FA8H1 in these five cell lines from lowest to highest were SMMC-7721, SK-HEP-1, HepG2, QCY-7701 and BEL-7402. c: Serial biodistribution of 131l-labeled anti-VEGFR2 cFab in nude mice bearing BEL-7402 (high expression of VEGFR2) tumors (n = 6 at each time point). At 24 h, 18.31% (±1.31) of injected activity was found in the tumors at the peak, whereas blood activity had already fallen to 9.57% (±0.46) and levels in other normal tissues were even lower. At 48 h, there was good retention of activity within tumors at 17.05% (±1.28) of injected activity, whereas blood activity was further fallen to 4.28% (±0.22).
