Biology subjects

Visser, L. G.

Publications and source records attributed to Visser, L. G..

2 recordsLinked to original sources

bioRxiv2025

Immuno-functionomics reveals geographical variation and a role for TLR8 in mRNA vaccine responses

The innate immune system plays a pivotal role in pathogen defense via pattern recognition receptor sensing, initiating responses upon infection or vaccination. Understanding its functional capacity is crucial for deciphering correlates of vaccine efficacy and understanding responses to infection. In this study, we developed a holistic approach to study immune function, generating >3100 readouts across 16 cell types, 18 pattern recognition receptors and 11 produced cytokines using spectral flow cytometry. To explore geographical variation, we studied the immune system of Europeans, urban, and rural Indonesians. We found differences in immune responses, such as increased IL1{beta} production in rural Indonesians and impaired IFN{gamma} production by innate lymphocytes after TLR8 stimulation. In Europeans vaccinated with mRNA-1273, baseline IFN{gamma} production by innate lymphocytes correlated with SARS-CoV-2 Spike-specific immune responses. In vitro mRNA vaccine stimulation also induced IFN{gamma} production, which was TLR8-dependent and reduced in rural Indonesians. This study highlights functional immune diversity and TLR8s potential role in mRNA vaccine responses. SummaryWe developed an approach to study the function capacity of the immune system, exploring geographical variation and mRNA vaccine responses. This revealed TLR8s potential role in responding to mRNA vaccines, and an impairment in this pathway in rural Indonesians.

immunology↗

bioRxiv2024

Bivalent COVID-19 vaccines boost the capacity of pre-existing SARS-CoV-2-specific memory B cells to cross-recognize Omicron subvariants

Bivalent COVID-19 vaccines comprising ancestral Wuhan-Hu-1 (WH1) and the Omicron BA.1 or BA.5 subvariant elicit enhanced serum antibody responses to emerging Omicron subvariants. We characterized the memory B-cell (Bmem) response following a fourth dose with a BA.1 or BA.5 bivalent vaccine, and compared the immunogenicity with a WH1 monovalent fourth dose. Healthcare workers previously immunized with mRNA or adenoviral vector monovalent vaccines were sampled before and one-month after a monovalent, BA.1 or BA.5 bivalent fourth dose COVID-19 vaccine. RBD-specific Bmem were quantified with an in-depth spectral flow cytometry panel including recombinant RBD proteins of the WH1, BA.1, BA.5, BQ.1.1, and XBB.1.5 variants. All recipients had slightly increased WH1 RBD-specific Bmem numbers. Recognition of Omicron subvariants was not enhanced following monovalent vaccination, while both bivalent vaccines significantly increased WH1 RBD-specific Bmem cross-recognition of all Omicron subvariants tested by flow cytometry. Thus, Omicron-based bivalent vaccines can improve recognition of descendent Omicron subvariants by pre-existing, WH1-specific Bmem, beyond that of a conventional, monovalent vaccine. This provides new insights into the capacity of variant-based mRNA booster vaccines to improve immune memory against emerging SARS-CoV-2 variants.

immunology↗