Year: 2024
Type: article
Abstract: Despite documentation of an immunological synapse >26 y ago, 1 most of our current understanding of immune cell interactions during alloimmune response is largely based on indirect evidence.The advent of single-cell technologies has unraveled an unanticipated heterogeneity across immune cells, 2 underscoring the critical need to understand cellto-cell interactions to fully decipher how immune responses are orchestrated.Spatial transcriptomics and high-density imaging, 3 as well as advanced intra-vital imaging techniques, have significantly contributed to the definition of cell interplay.4 However, understanding the temporal dynamics of cell-to-cell communication and how these interactions impact their transcriptional program is still a major unmet need.In 2018, Pasqual et al 5 developed a strategy to trace receptor/ligand-specific interactions between dendritic cells and CD4 + T cells (labeling immune partnership by SorTagging intercellular contacts [LIPSTIC]).More recently, the same group presented an upgraded version of this tool that offers a way to capture transient interactions between cells of the immune system that come into close physical proximity with any other cells in the organism: the universal LIPSTIC (uLIPSTIC).6 The technique exploits a low-affinity interaction between 2 molecules: a bacterial enzyme (Staphylococcus aureus enzyme Sortase A, SrtA) on the surface of a donor cell and its target, a stretch of 5 glycine amino acid residues (G 5 ) on the surface of an acceptor cell.SrtA catalyzes the transfer of a biotin-labeled peptide substrate to G 5 , which is part of a protein on the acceptor cell surface.The transfer from SrtA-expressing to G 5 -expressing cells happens only when donor and acceptor cells are in close proximity (< 14 nm; Figure 1).The authors engineered a mouse allele carrying membrane-targeted SrtA and G 5 in the Rosa26 locus to ensure robust and ubiquitous expression of uLIPSTIC.Using mice with lineage-specific Cre recombinase, mSrtA can be conditionally expressed in a specific cell subset, allowing the labeling of interacting cells that can later be identified by flow cytometry analysis of biotin labeling.
Source: Transplantation
Authors: Nina Goerlich, Paolo Cravedi
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W4400964641