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bioRxiv · 10.1101/2020.08.13.250274

Maternal schistosomiasis impairs offspring IL-4 production and B cell expansion

Abstract

Maternal helminth infections are a global public health concern and correlate with altered infant immune responses to some childhood immunizations, but a mechanistic understanding of how maternal helminth infection alters the cellular immune responses of offspring is lacking. Here we establish a model of maternal Schistosoma mansoni infection in dual IL-4 reporter mice. We find that offspring born to mothers infected with S. mansoni have impaired production of IL-4 during homoeostasis, and following immunization with a Tetanus-Diphtheria vaccine. We identified that iNKT cells are the dominant source of IL-4 during early life homeostasis, and that diminished IL-4 production was associated with both reduced B cell and follicular dendritic cell responses. These defects were maintained long-term, affecting memory B and T cell responses. Single-cell RNASeq analysis of immunized offspring identified egg antigen-dependent reductions in B-cell cell cycle and proliferation-related genes. These data reveal that maternal infection leads to long-lasting defects in the cellular responses to heterologous antigens and provide vital insight into the influence of maternal infection on offspring immunity.

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Cortes-Selva, D., Gibbs, L., Ekiz, H. A., Rajwa, B., Fairfax, K. C.. 2020-08-14. Maternal schistosomiasis impairs offspring IL-4 production and B cell expansion. https://doi.org/10.1101/2020.08.13.250274

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