Pre-existing anti-polyethylene glycol antibodies in pregnant women and newborns

Pre-existing anti-polyethylene glycol (PEG) antibodies represent risk factors for reduced efficacy and increased adverse reactions in seropositive individuals, but neither the seropositivities, nor levels nor influencing factors have been investigated in pregnant women or newborns. Herein, maternal and cord blood samples were respectively collected from 256 pregnant women and corresponding 256 newborns at the Women's Hospital, Zhejiang University School of Medicine in China for further determination of pre-existing anti-PEG antibodies, along with questionnaire interviews, demographic and clinical data collections. Our data showed that the seropositivities of total anti-PEG antibodies, anti-PEG IgG1 and IgG2, anti-PEG IgM, and coexistence of anti-PEG IgM and IgG were 19.14%, 2.34%, 7.03%, 10.94% and 1.17%, respectively, in pregnant women, and 5.47%, 2.73%, 2.73%, 0% and 0%, respectively, in newborns. Anti-PEG IgG3, IgG4 and IgE were undetectable in all blood samples. Median anti-PEG IgG1, IgG2 and IgM concentrations were 273.88 ng/mL, 748.35 ng/mL and 175.07 ng/mL, respectively, in pregnant women. Median anti-PEG IgG1 and IgG2 concentrations were 207.92 ng/mL and 336.52 ng/mL, respectively, in newborns. Interestingly, in-depth statistical analyses revealed that maternal age, take-out food consumption and cosmetic use were influencing factors of maternal anti-PEG antibodies, while newborn anti-PEG antibodies were affected by maternal age and cosmetic use. These seroepidemiological characteristics raise concerns over the clinical use of PEGylated drugs in pregnant women and newborns, and provide valuable insight into the induction of risky pre-existing anti-PEG antibodies.