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de Haas, L.

Publications and source records attributed to de Haas, L..

2 recordsLinked to original sources

Spatiotemporal proteomics elucidates trafficking and localization of Neuroligins to the axon initial segment plasma membrane

Neuronal development and function rely on precise sorting of membrane proteins to distinct neuronal domains, yet the underlying mechanisms remain incompletely understood. Here, we investigated the trafficking of two highly homologous NLGNs (NLGN1 and 2) which distinctly localize and function at excitatory and inhibitory synapses. By using spatiotemporal proteomics, genetic engineering and microscopy in CNS cultured neurons and organotypic slices, we dissected the itinerary of biosynthetic NLGNs, identifying co-cargoes and sorting routes to dendrites and the AIS. At the AIS, which contains only inhibitory synapses, both NLGN1 and NLGN2 are locally exocytosed. While NLGN2 is stably recruited to axo-axonic synapses by its extracellular domain and modulated by activity, NLGN1 is retrieved by endocytic mechanisms. We propose that biosynthetic NLGNs are co-sorted to the AIS PM where they detect pre-synaptic type. These findings may help to elucidate the role of AIS-localized NLGNs in shaping AIS structural and functional plasticity. HighlightsO_LISpatiotemporal proteomics elucidates interactome of biosynthetic NLGN1 in neurons C_LIO_LINLGN1 and NLGN2 are targeted to the AIS by kinesin-1 C_LIO_LINLGN2, but not NLGN1, is retained at axo-axonic synapses and modulated by activity C_LIO_LINLGN stability at the AIS plasma membrane is determined by the ectodomain C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=194 HEIGHT=200 SRC="FIGDIR/small/733123v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@a45909org.highwire.dtl.DTLVardef@1d171b0org.highwire.dtl.DTLVardef@17f132aorg.highwire.dtl.DTLVardef@1c33a8d_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

Efficient targeting of NY-ESO-1 tumor antigen to human cDC1s by lymphotactin results in cross-presentation and antigen-specific T cell expansion

Type 1 conventional dendritic cells (cDC1s) are characterized by their ability to induce potent CD8+ T cell responses. In efforts to generate novel vaccination strategies, notably against cancer, human cDC1s emerge as an ideal target to deliver antigens. cDC1s uniquely express XCR1, a seven transmembrane G protein-coupled receptor (GPCR). Due to its restricted expression and endocytic nature, XCR1 represents an attractive receptor to mediate antigen-delivery to human cDC1s. To explore tumor antigen delivery to human cDC1s, we used an engineered version of XCR1-binding lymphotactin (XCL1), XCL1(CC3). Site-specific sortase-mediated transpeptidation was performed to conjugate XCL1(CC3) to an analog of the HLA-A*02:01 epitope of the cancer testis antigen New York Esophageal Squamous Cell Carcinoma-1 (NY-ESO-1). While poor epitope solubility prevented isolation of stable XCL1-antigen conjugates, incorporation of a single polyethylene glycol (PEG) chain upstream of the epitope-containing peptide enabled generation of soluble XCL1(CC3)-antigen fusion constructs. Binding and chemotactic characteristics of the XCL1-antigen conjugate, as well as its ability to induce antigen-specific CD8+ T cell activation by cDC1s, was assessed. PEGylated XCL1(CC3)-antigen conjugates retained binding to XCR1, and induced cDC1 chemoattraction in vitro. The model epitope was efficiently cross-presented by human cDC1s to activate NY-ESO-1-specific CD8+ T cells. Importantly, vaccine activity was increased by targeting XCR1 at the surface of cDC1s. Our results present a novel strategy for the generation of targeted vaccines fused to insoluble antigens. Moreover, our data emphasize the potential of targeting XCR1 at the surface of primary human cDC1s to induce potent CD8+ T cell responses.

immunology↗