Antigen presenting cells: Professionals, amateurs, and spectators in the 'long game' of lung immunity

• Published in: The international journal of biochemistry & cell biology 2022-12, Vol.153, p.106331-106331, Article 106331
• Main Authors: Hargrave, Kerrie E., MacLeod, Megan K.L., Worrell, Julie C.
• Format: Article
• Language: English
• Subjects: Antigen-presentation; Influenza; Lung stromal cells
• ISSN: 1357-2725; 1878-5875
• DOI: 10.1016/j.biocel.2022.106331

The lung is frequently and repeatedly exposed to invading pathogens and thus requires constant immunosurveillance. Professional antigen presenting cells (APCs), including dendritic cells, engulf invading pathogens and present their peptides via major histocompatibility complexes (MHC) I and II, to CD8 or CD4 T cells. Epithelial cells and stromal cells (including fibroblasts) provide more than structural support, they are increasingly recognised as key players in the immune response, acting as non-professional APCs through interactions with antigen experienced T cells that migrate to the lung. The importance of the contributions of non-professional and professional APCs to T cell function in vivo, is currently unclear. This review summarises the roles of professional and non-professional APCs in lung immunity, at the steady state and following viral insult, with particular emphasis on their ability to interact with and influence T cells. •The lung contains various populations of professional and non‑professional antigen presenting cells.•Memory T cell reactivation by diverse antigen-presenting cells may drive distinct functional responses post infection.•Using specific APC subsets to facilitate targeted reactivation of memory T cells may enhance vaccine efficacy.