Fig. 1:

IgM levels (mean ± SD) of anti-self A/B blood group (auto) antibodies, anti-A/B-Incompatible blood group (anti-AB-I) antibodies, and anti-galactose-α1,3-galactose (Gal) antibodies, in naïve baboons (n=6). There were undetectable IgM levels of anti-AB-I blood group antibodies, and anti-Gal antibodies at one month of age in naïve infant baboons, comparable with anti-self (optical density<0.2). Thereafter, anti-AB-I IgM increased slowly and anti-Gal IgM rose more rapidly with increasing age. (Reprinted with permission from Dons et al. 2012.)