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Linterman, M. A.

Publications and source records attributed to Linterman, M. A..

3 recordsLinked to original sources

The memory B cell response to influenza vaccination is impaired in older persons

Influenza imparts an age-related increase in mortality and morbidity. The most effective countermeasure is vaccination; however, vaccines offer modest protection in older adults. To investigate how ageing impacts the memory B cell response we tracked haemagglutinin specific B cells by indexed flow sorting and single cell RNA sequencing in twenty healthy adults administered the trivalent influenza vaccine. We found age-related skewing in the memory B cell compartment six weeks after vaccination, with younger adults developing haemagglutinin specific memory B cells with an FCRL5+ "atypical" phenotype, showing evidence of somatic hypermutation and positive selection, which happened to a lesser extent in older persons. We confirmed the germinal center ancestry of these FCRL5+ "atypical" memory B cells using scRNASeq from fine needle aspirates of influenza responding human lymph nodes and paired blood samples. Together, this study shows that the aged human germinal center reaction and memory B cell response following vaccination is defective. SummaryImmune responses to vaccination wane with age. Using single cell RNA sequencing of influenza vaccine specific B cells, this study delineates changes in B cell memory generation, antibody mutation and their subsequent selection in older persons.

immunology

A booster dose enhances immunogenicity of the COVID-19 vaccine candidate ChAdOx1 nCoV-19 in aged mice

The spread of SARS-CoV-2 has caused a global pandemic that has affected almost every aspect of human life. The development of an effective COVID-19 vaccine could limit the morbidity and mortality caused by infection, and may enable the relaxation of social distancing measures. Age is one of the most significant risk factors for poor health outcomes after SARS-CoV-2 infection, therefore it is desirable that any new vaccine candidates should elicit a robust immune response in older adults. Here, we test the immunogenicity of the adenoviral vectored vaccine ChAdOx1 nCoV-19 (AZD-1222) in aged mice. We find that a single dose of this vaccine induces cellular and humoral immunity in aged mice, but at a reduced magnitude than in younger adult mice. Furthermore, we report that a second dose enhances the immune response to this vaccine in aged mice, indicating that a primeboost strategy may be a rational approach to enhance immunogenicity in older persons.

immunology

Intrinsic defects in lymph node stromal cells underpin poor germinal center responses during aging

The failure to generate enduring humoral immunity after vaccination is a hallmark of advancing age. This can be attributed to a reduction in the germinal center response, which generates long-lived antibody-secreting cells that provide protection against (re)infection. Despite intensive investigation into the effect of age on the lymphoid compartment, the primary cellular defect that causes impaired germinal centers in aging has not been identified. Herein we demonstrate that aging reduces the capacity of germinal center-associated stromal cells to respond to vaccination. Heterochronic parabiosis and mathematical modeling demonstrate that a poor stromal cell response limits the size of the germinal center. This study reveals that age-associated defects in stromal cells are a significant barrier to efficacious vaccine responses in older individuals.

immunology