Bordetella pertussis booster vaccine responses in pregnant women primed with whole-cell vaccine

ZURITA, EUGENIA; BOTTERO, DANIELA; MARTIN AISPURO, PABLO; PSCHUNDER, BERNARDA; WLASIUK, A; AZCARRIAGA, P.; GOMEZ, F; TORO, ROSANA; FEDELE, GIORGIO; HOZBOR, DANIELA

Simposio; 13th International Bordetella Symposium; 2022

Pertussis is a highly contagious respiratory disease that affects most severely to the infant population in risk from severe disease and death. The resurgence of pertussis in recent years has forced to review and implement new strategies for disease prevention. One of the short-term strategies has been the introduction of maternal immunization during the pregnancy. Argentina has been a pioneer in implementing this strategy. The aim of the present work was to evaluate the immune response induced by maternal immunization both in the mother and the newborns. For this matter, blood samples from pregnant women with or without maternal immunization, umbilical cord and kids from different ages were collected in San Roque Gonnet Hospital and processed to characterize the humoral and cellular immune response against pertussis. A total of 103 samples were collected, including 44 samples from pregnant women, 24 cord blood and 35 samples of kids between 1m and 11 years of age. We found that total IgG against PT was detectable in pregnant women with less than 2 months since immunization (266 ± 86,95) in comparison with non-vaccinated mothers (163 ± 56,15). Three months after vaccination more than 70% of the women were able to produce IFN in response to PT in comparison to non-vaccinated mothers (25%), and IL-17 (55% in vaccinated mothers vs 17% in non-immunized). In concordance, in cord blood from vaccinated mothers after 2 months we found high titters of total IgG (435,1 ± 66,88) and a Th1/Th17 cellular immune response (IFN: 32,08 ± 10,12, IL-17: 6,18 ± 0,91).Regarding to the kids samples we found that both humoral and cellular immune responses against PT were higher on eleven-year-old kids who had recently been boostered with aP, in comparison with younger kids that had only been vaccinated with whole cell vaccine (primary schedule).These results seem to agree with the ones reported previously by Sette et all (2018) showing that aP boost in the context of whole cell priming induces a Th1/Th17 cellular immune response. This was evidence both in the context of kids and vaccinated mothers, showing that aP boost is a good strategy to elicit a good Th1/Th17 response that con confer protection to newborns.