Mechanisms of maternally conferred protection in a neonatal mouse model 3862

Abstract Description Bordetella pertussis (Bp), the etiological agent of whooping cough, is known to cause respiratory illness in infants. Although vaccines are available, newborns aren’t recommended to receive them until at least 2 months of age, leaving them vulnerable to severe infections. To combat this, expecting mothers are recommended to get booster pertussis vaccine between 27-36 weeks’ gestation. While maternal vaccinations result in decreased pertussis-related hospitalization in newborns, the mechanisms behind this protection has yet to be defined. Using a neonatal murine model, we show that maternal vaccination confers rapid protection in the lungs of neonates through the transfer of maternal immune components. By studying the immunocompetent offspring of immunodeficient dams vaccinated against Bp, we show that maternal B and T cells are required for maternal vaccines to protect neonates. By blocking the transfer of Bp specific antibodies to offspring, we demonstrate that maternal antibodies are not the only mechanism of protection conferred to offspring. Instead, we demonstrate that Bp-specific CD4+ T cells are required in combination with efficient antibody transfer to result in protection. Better understanding of the mechanisms by which maternal vaccination protects vulnerable neonates will inform the development of this relatively new vaccination strategy. Funding Sources NIH AI142678, NIH AI139449 and NIH AI182884 Topic Categories Mucosal and Regional Immunology (MUC)