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Biology subjects

Provine, N.

Publications and source records attributed to Provine, N..

3 recordsLinked to original sources

Distinct transcriptional states of draining lymph node T cells following influenza vaccination in individuals with underrepresented ancestries

The transcriptional and cell repertoire changes of lymph node (LN) T cells following influenza vaccination have been under-investigated across different ethnicities. Draining (dLN) and non-draining (ndLN) axillary LN cells from 17 participants with genotypically varied African or Asian ancestry (ISRCTN13657999) were collected by fine needle aspiration (FNA) before, 5 days and 42 days after adjuvanted influenza vaccination and analysed by single-cell RNA-sequencing (scRNA-seq). The early dLN transcriptional profile and cellular dynamics were distinct from the ndLN; BACH2 expressing T cells were highly induced, exhibiting stem-like and unique quiescence signatures. Proliferating T follicular helper cells (Tfh) were enriched in dLN and Th1-like Tfh predominated with highly induced transcriptional changes. The BACH2+ T cell state and Th1-like Tfh cells, transcriptionally distinct from germinal centre (GC) T cells, were co-localised with LAMP3+ dendritic cells in the T cell zone of publicly available LN datasets, a region that was also distinct from GC Tfh niches. Together, these findings indicate that the induction of a robust, proliferative, and transcriptionally diverse Tfh response, alongside a discrete subset of BACH2+ T cells, represents a marked feature of the early T cell zone immune response to adjuvanted influenza vaccine in the dLN.

immunology↗

Neurodegenerative fluid biomarkers are enriched in human cervical lymph nodes

In animal models, brain neurodegeneration biomarkers drain into cervical lymph nodes (CLNs). If this occurred in humans, CLNs may provide a readily accessible source of these biomarkers, draining the site of primary pathology. We tested this hypothesis in discovery and validation cohorts using ultrasound-guided fine needle aspiration (FNA). We measured amyloid-beta 40 and 42, phospho-Tau-181, glial-fibrillary-acidic-protein, and neurofilament-light using single molecule array in CLN aspirates and plasma from: i) a discovery cohort of 25 autoimmune patients, and from ii) plasma, CLNs and capillary blood in four healthy volunteers, an optimisation-validation cohort. FNA was well-tolerated by all participants. In both cohorts, all biomarkers were detected in all plasmas and CLNs, other than neurofilament-light (8/17 of discovery cohort). CLN biomarker concentrations were significantly greater than plasma concentrations for all except neurofilament-light, most markedly for phospho-Tau-181 (266 fold; P<0.02), whose CLN concentrations decreased with age (Spearman r=-0.66, P=0.001). This study presents the first evidence that neurodegenerative biomarkers are detectable in human CLNs. Raised CLN:plasma biomarker ratios suggest their concentration in CLNs, which may offer a sensitive compartment for minimally-invasive sampling in clinical trials. Further, age-associated phospho-Tau-181 reduction with age suggests FNA of CLNs may measure the integrity of brain lymphatic drainage in vivo.

neuroscience↗

Activation of MAIT cells plays a critical role in viral vector vaccine immunogenicity

Mucosal-associated invariant T (MAIT) cells can be activated by viruses through a cytokine-dependent mechanism, and thereby protect from lethal infection. Given this, we reasoned MAIT cells may have a critical role in the immunogenicity of replication-incompetent adenovirus vectors, which are novel and highly potent vaccine platforms. In vitro, ChAdOx1 (Chimpanzee Adenovirus Ox1) induced potent activation of MAIT cells. Activation required transduction of monocytes and plasmacytoid dendritic cells to produce IL-18 and IFN-, respectively. IFN--induced monocyte-derived TNF- was identified as a novel intermediate in this activation pathway, and activation required combinatorial signaling of all three cytokines. Furthermore, ChAdOx1-induced in vivo MAIT cell activation in both mice and human volunteers. Strikingly, MAIT cell activation was necessary in vivo for development of ChAdOx1-induced HCV-specific CD8 T cell responses. These findings define a novel role for MAIT cells in the immunogenicity of viral vector vaccines, with potential implications for future design.\n\nOne sentence summaryRobust immunogenicity of candidate adenovirus vaccine vectors requires the activation of unconventional T cells.

immunology↗