High SARS-CoV-2 antibody levels after three consecutive BNT162b2 booster vaccine doses in nursing home residents.

Background: As older age and having certain comorbidities can influence humoral responses to vaccination, we studied antibody responses after the COVID-19 booster campaigns in nursing home (NH) residents.

Methods: In a two year longitudinal study with Dutch NH residents (n = 107), aged 50 years and over, we monitored antibody responses in serum prior to and after vaccination with a third, fourth BNT162b2 (wild-type; WT), and a BNT162b2 bivalent (WT/OMI BA.1) fifth vaccine.

Association of baseline cytokines with antibody concentrations after diphtheria-tetanus-acellular pertussis booster vaccination in Finnish children.

Background: Despite extensive vaccinations, pertussis remains endemic and epidemic in multiple countries. The persistence of cases can be partly attributed to the significant individual variation in vaccine responses. This study evaluated the association of baseline cytokines (before booster vaccination) on antibody concentrations to Tdap-vaccine antigens.

A literature review and evidence-based evaluation of the Dutch national immunisation schedule yield possibilities for improvements.

National Immunisation Programmes (NIPs) develop historically. Its performance (disease incidences, vaccination coverage) is monitored. Reviewing the schedule as a whole could inform on further optimisation of the programme, i.

Health characteristics associated with persistence of SARS-CoV-2 antibody responses after repeated vaccinations in older persons over time: the Doetinchem cohort study.

Background: Older persons elicit heterogeneous antibody responses to vaccinations that generally are lower than those in younger, healthier individuals. As older age and certain comorbidities can influence these responses we aimed to identify health-related variables associated with antibody responses after repeated SARS-CoV-2 vaccinations and their persistence thereafter in SARS-CoV-2 infection-naïve and previously infected older persons.

Method: In a large longitudinal study of older persons of the general population 50 years and over, a sub-cohort of the longitudinal Doetinchem cohort study (n = 1374), we measured IgG antibody concentrations in serum to SARS-CoV-2 Spike protein (S1) and Nucleoprotein (N).

Repeated COVID-19 mRNA vaccination results in IgG4 class switching and decreased NK cell activation by S1-specific antibodies in older adults.

Background: Previous research has shown that repeated COVID-19 mRNA vaccination leads to a marked increase of SARS-CoV-2 spike-specific serum antibodies of the IgG4 subclass, indicating far-reaching immunoglobulin class switching after booster immunization. Considering that repeated vaccination has been recommended especially for older adults, the aim of this study was to investigate IgG subclass responses in the ageing population and assess their relation with Fc-mediated antibody effector functionality.

Results: Spike S1-specific IgG subclass concentrations (expressed in arbitrary units per mL), antibody-dependent NK cell activation, complement deposition and monocyte phagocytosis were quantified in serum from older adults (n = 38-50, 65-83 years) at one month post-second, -third and -fifth vaccination.