Here, Tdap booster doses overcame an initially observed blunting effect caused by high maternal antibody levels (95, 96). Approaches seeking to bypass the process of blunting are nowadays tested, such as alternative vaccination routes and the simultaneous injection of antigen-specific IgM or agents that stimulate the production of interferon- along with the vaccine (68). a large number of pre-and postconceptional vaccine trials have been carried out to test and confirm this concept. We here highlight novel insights arising from recent research endeavors on the influence of prenatal maternal vaccination against pathogens that can pose a threat for newborns, such as measles, pertussis, rubella and influenza A. We delineate pathways involved in the transfer of specific maternal antibodies. We also discuss the consequences for childrens health and long-term immunity resulting from an adjustment of prenatal vaccination regimes. Keywords: maternal vaccination, measles, rubella, pertussis, influenza, FcRn, blunting, breastfeeding Early Life Immunity and Time Windows Permitting Pathogen Threats for Neonates After birth and during their first months of life, human newborns are not yet equipped with a fully matured immune system (1, 2). Hence, they are highly susceptible to infectious pathogens, such as measles, pertussis, rubella, and influenza. These pathogens can cause a severe course of disease in neonates and infants, which may even be fatal (3C5). The availability of safe and immunogenic vaccines against infectious diseases, i.e., the combined measles-mumps and rubella vaccine, does not mitigate this threat to neonatal health, as the vaccines contain living pathogen components; hence, their use is not recommended to be administered to children under the age of 12 months. Similarly, the vaccination with the combined tetanus-diphtheria-pertussis (Tdap) vaccine and the inactivated influenza vaccines (IIV) is Pseudouridimycin not recommended until 2 or 6 months of age, respectively (6, 7). These restrictions to vaccination leave a pivotal gap of neonatal immunity against these pathogens until routine immunization can be administered (8). This gap in immunity is C at least in part C covered by the active, transplacental transfer of maternal pathogen-specific antibodies. Mothers convey passive immunity to their newborns through the transplacental transfer of antibodies, hereby providing a shield for the infant from pathogen-mediated diseases (1, 9). The amount of transferred antibodies can differ between individuals and is mainly dependent on maternal antibody concentrations (10, 11). Based on this natural immunity mediated by the mother, maternal vaccination strategies during pregnancy are vividly discussed. Such strategies could increase maternal antibody concentrations, enhance the levels of transplacental antibody transfer and, in consequence, the degree of passive immunity for the neonate (12). In the light of the recent outbreaks of vaccine-preventable diseases such as Pseudouridimycin measles even in countries with high vaccine Pseudouridimycin coverage, the topic of immunization has received significant attention by medical professionals and the lay community. Measles infection has caused more than 140,000 deaths globally in 2018, most of them among children under five years of age (13). Promoting the immunity of newborns via maternal vaccination holds the potential to become an effective and low-cost approach to prevent neonatal morbidity and mortality caused by communicable diseases (14C16). In the present article, we comprehensively discuss recent research studies on maternal vaccination against common childhood infections such as pertussis, influenza, measles, and rubella. We further highlight pathways involved in the transplacental transfer of antibodies as well as mechanisms through which neonatal immunity can be improved irrespective of maternal antibodies (Figure 1). Open in a separate window FIGURE 1 Overview of maternal immunity and recommended vaccinations before, during and after pregnancy as well as consequences for maternal and childrens health. Observations From Vaccination Studies Against Tetanus, Diphtheria and Pertussis During Pregnancy A number of recent studies confirm that vaccination with the combined tetanus, diphtheria, and acellular pertussis vaccine (Tdap) can be recommended during pregnancy, since vaccine trials carried out on a large scale and in various countries have generally demonstrated its safety and immunogenicity in mothers and their infants (Table 1). The World Health Organization (WHO) reports a Rabbit polyclonal to IL13 96% reduction of death by neonatal tetanus through implementation of recommended elimination practices from 1988 to 2015, including the vaccination of pregnant women (17). Similarly, the burden of diphtheria disease has been reduced (18). Unfortunately, comparable achievements have not been made with regard to pertussis elimination. Outbreaks of whooping cough have recently been occurring worldwide, exposing young infants to a particularly high risk of severe infections. Thus, we here mainly discuss studies that focus on the outcome of pertussis vaccination in pregnant women. TABLE 1 Overview of studies and.
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