Fig 1: Secondary antibody crosslinking does not confer IMV-M cytotoxicity in hepatic cell lines. (A) Increasing the secondary antiserum:IMV-M ratio modestly enhances IMV-M cytotoxicity toward OVCAR-3 cells at intermediate ratios, whereas higher ratios reduce activity, defining an optimal enhancement range. (B) IMV-M does not induce cytotoxicity in hepatic cell lines. (C) and (D) IMV-M does not induce cytotoxicity in hepatic cell lines across the entire tested range of secondary antiserum:IMV-M ratios. Cells were treated with IMV-M ± polyclonal rabbit antihuman IgG1 Fc (Sino Biological 10702-T16), and cytotoxicity was assessed by CellTiter-Glo. Data are presented as mean ± SD (n = 3). Student’s unpaired t-test was used for the ELISA experiments. The difference between the positive (+IMV-M) and control (no IMV-M) groups in (B) was highly significant for OVCAR-3 cells (P < .01) and not significant (P > .05) for HepG2 and Hep3B cells.