FIGURE 1.
Comparison of mean IgM (left)/IgG (middle) binding and CDC (right) of baboons (n = 72) to GTKO, GTKO/β4GalNT2KO, and TKO pig PBMCs. On the y axis, the dotted line represents the cut-off values (IgM [rGM] 1.2, IgG [rGM] 1.1, CDC 6.4%) below which there is no binding or cytotoxicity, as previously described.10 The red lines indicate the mean values. (*P < 0.05, **P < 0.01; ns = not significant). Most baboons have low levels of IgM and IgG binding to GTKO/β4GalNT2KO PBMCs, and approximately 50% have a low levels of CDC to these cells. CDC, complement-dependent cytotoxicity; GTKO, α1,3-galactosyltransfearse gene-knockout; TKO, triple-knockout.