Understanding more about maternal vaccination and neonatal immunity to improve vaccine induced protection in early life
File(s)
Author(s)
Zhong, Ziyun
Type
Thesis
Abstract
Neonates are more susceptible to infectious diseases and often have worse disease outcomes. Influenza virus, Respiratory Syncytial Virus (RSV) and Streptococcus agalacticae (Group B Streptococcus: GBS) are three major pathogens associated with neonatal infections. Maternal and neonatal vaccination are two promising strategies to protect this vulnerable population.
Maternal influenza vaccination has been clinically proven to be effective in protecting both the mothers and newborns. However, the limited half-life of antibody response reduces the effectiveness of protection in infants leaving them highly susceptible to infection. More understanding of the complete picture of how the timing of maternal vaccination affects the antibody responses in both the mothers and their newborns is required. One objective of this study was to evaluate influenza specific antibody after vaccination at different stages of pregnancy in the mothers and their newborns. Maternal immunisation led to significantly more antibody in the infant blood, the highest antibody concentration was found in newborns when maternal vaccination was carried out 5-24 weeks before delivery.
Neonatal vaccination is an alternative option. However, neonates have different immune features compared to adults, including restricted functionality of the innate immune response and limited immune memory. Since these features play an essential role in shaping the subsequent direction of the vaccine induced response, studying the neonatal innate response to infections in comparison to adults may be instrumental to future neonatal vaccine development. Therefore, the other objective of this study was to investigate the neonatal innate immune response to influenza, RSV and GBS. Neonatal innate immune responses to viral and bacterial infection were characterised and compared, following by the study of innate immune cell phenotypes and the corresponding chemokine expression. Viral infection induced a different immune response pattern compared to bacterial infection. Interestingly, neonates display similar overall immune profiles when compared with adults, with the exception of the chemokine responses.
These studies provide immunological underpinning for the future development of effective maternal and neonatal vaccines.
Maternal influenza vaccination has been clinically proven to be effective in protecting both the mothers and newborns. However, the limited half-life of antibody response reduces the effectiveness of protection in infants leaving them highly susceptible to infection. More understanding of the complete picture of how the timing of maternal vaccination affects the antibody responses in both the mothers and their newborns is required. One objective of this study was to evaluate influenza specific antibody after vaccination at different stages of pregnancy in the mothers and their newborns. Maternal immunisation led to significantly more antibody in the infant blood, the highest antibody concentration was found in newborns when maternal vaccination was carried out 5-24 weeks before delivery.
Neonatal vaccination is an alternative option. However, neonates have different immune features compared to adults, including restricted functionality of the innate immune response and limited immune memory. Since these features play an essential role in shaping the subsequent direction of the vaccine induced response, studying the neonatal innate response to infections in comparison to adults may be instrumental to future neonatal vaccine development. Therefore, the other objective of this study was to investigate the neonatal innate immune response to influenza, RSV and GBS. Neonatal innate immune responses to viral and bacterial infection were characterised and compared, following by the study of innate immune cell phenotypes and the corresponding chemokine expression. Viral infection induced a different immune response pattern compared to bacterial infection. Interestingly, neonates display similar overall immune profiles when compared with adults, with the exception of the chemokine responses.
These studies provide immunological underpinning for the future development of effective maternal and neonatal vaccines.
Version
Open Access
Date Issued
2017-12
Date Awarded
2019-02
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Tregoning, John
Kampmann, Beate
Publisher Department
Department of Medicine
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Master of Philosophy (MPhil)