{
  "abstract": "Interleukin-15 (IL-15) trans-presentation (TP) by B cells is an important mechanism of T-cell activation; however, the spatial organisation of interleukin-15 receptor (IL-15R) relative to major histocompatibility complex (MHC) molecules on B-cell microvilli remains poorly understood. As microvilli protrude from the B-cell surface and may serve as sites of initial B cell-T-cell contact, the distribution of IL-15R and MHC molecules within these structures may be important during the earliest stages of T-cell recognition and activation. Here, we investigated the spatial association and molecular proximity of IL-15R with MHC class I and class II molecules on B-cell microvilli before immunological synapse formation, using confocal microscopy, stimulated emission depletion (STED) microscopy, stochastic optical reconstruction microscopy (STORM), and fluorescence lifetime imaging microscopy-based Forster resonance energy transfer (FLIM-FRET). Both MHC class I and class II molecules showed significant spatial association with IL-15R; however, the extent of colocalisation decreased as spatial resolution increased. STED microscopy revealed significant colocalisation between IL-15R and MHC class I, whereas STORM did not detect this association. In contrast, IL-15R and MHC class II remained significantly colocalised at both resolutions. FLIM-FRET further demonstrated molecular proximity between IL-15R and both MHC class I and class II molecules, with higher FRET efficiency observed for MHC class II. Collectively, these findings indicate that IL-15R is spatially organised in proximity to both MHC class I and class II molecules on B-cell microvilli before immunological synapse formation. This arrangement at potential sites of initial B-cell-T-cell contact may facilitate the coordination of IL-15 trans-presentation and antigen presentation during the earliest stages of B-cell-T-cell interactions.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": "New results",
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "name": "I. Rebenku"
    },
    {
      "name": "N. Bilakovics"
    },
    {
      "name": "L. Szolyka"
    },
    {
      "name": "L. Velas"
    },
    {
      "name": "T. Garda"
    },
    {
      "name": "G. J. Schütz"
    },
    {
      "name": "G. Vamosi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/799tvv71gyyaj.bib",
  "cited_by": 0,
  "doi": "10.64898/2026.09.24.747988",
  "fulltext_url": "https://www.biorxiv.org/content/10.64898/2026.09.24.747988v1.full",
  "id": "799tvv71gyyaj",
  "issns": [],
  "landing_url": "https://www.biorxiv.org/content/10.64898/2026.09.24.747988v1",
  "language": null,
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "biorxiv",
      "cell biology"
    ],
    [
      "openalex",
      "2403|T-cell and B-cell Immunology"
    ]
  ],
  "openalex": "W7214278599",
  "pdf_url": "https://www.biorxiv.org/content/10.64898/2026.09.24.747988v1.full.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-24",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/799tvv71gyyaj.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:24:32Z",
      "native_id": "10.64898/2026.09.24.747988",
      "source": "biorxiv",
      "url": "https://www.biorxiv.org/content/10.64898/2026.09.24.747988v1"
    }
  ],
  "subjects": [
    {
      "field": "biology",
      "origin": "biorxiv:cell biology",
      "subfield": "cell-biology"
    }
  ],
  "title": "MHC Molecules on B Cell Microvilli Are Spatially Associated with IL-15Rα",
  "title_text": "MHC Molecules on B Cell Microvilli Are Spatially Associated with IL-15Rα",
  "type": "preprint",
  "updated_at": "2026-10-30T12:24:32Z",
  "url": "https://research.draconitic.com/paper/799tvv71gyyaj",
  "venue": "bioRxiv",
  "versions": []
}