Chemokine-Driven Spatial Niches Regulate Distinct APC-T cell Neighbourhoods within the Human Lymph Node — ASN Events

Chemokine-Driven Spatial Niches Regulate Distinct APC-T cell Neighbourhoods within the Human Lymph Node (#144)

Marcus Ooi 1 , Saem Park 1 2 , Rod Dunbar 1 2 , Jennifer Chen 1
  1. School of Biological Sciences, University of Auckland, Auckland, New Zealand
  2. Maurice Wilkins Centre, University of Auckland, Auckland, New Zealand

Upon capturing peripheral antigens, antigen-presenting cells (APCs) migrate to the lymph nodes (LNs) to prime naïve T cells. These T cells subsequently proliferate and differentiate into effector and memory populations capable of rapid antigen clearance. While precise communication between T cells and APCs is essential for an effective immune response, the chemokine signals driving their colocalisation and subsequent interactions remain poorly characterised in humans. We utilised multiplexed immunofluorescence (mIF) and whole-slide imaging of human LNs to identify distinct T-cell and APC zones defined by unique chemokine and receptor profiles. Spatial analysis of mIF data confirmed their colocalisation and suggested potential interactions, while spatial transcriptomics and single-cell RNA-seq further revealed the unique molecular signatures of cellular neighbourhoods composed of distinct APC and T-cell subsets. The protein expression of these signatures was validated using mIF staining. Our work highlights specialised spatial niches of DC-T cell interactions in the human LN, providing a framework for further investigation into their discrete roles in mediating T-cell responses.