Role of Mast Cells and Type 2 Innate Lymphoid (ILC2) Cells in Lung Transplantation

Abstract

The multifunctional role of mast cells (MCs) in the immune system is complex and has not fully been explored. MCs reside in tissues and mucous membranes such as the lung, digestive tract, and skin which are strategically located at interfaces with the external environment. These cells, therefore, will encounter external stimuli and pathogens. MCs modulate both the innate and the adaptive immune response in inflammatory disorders including transplantation. MCs can have pro- and anti-inflammatory functions, thereby regulating the outcome of lung transplantation through secretion of mediators that allow interaction with other cell types, particularly innate lymphoid cells (ILC2). ILC2 cells are a unique population of hematopoietic cells that coordinate the innate immune response against a variety of threats including infection, tissue damage, and homeostatic disruption. In addition, MCs can modulate alloreactive T cell responses or assist in T regulatory (Treg) cell activity. This paper outlines the current understanding of the role of MCs in lung transplantation, with a specific focus on their interaction with ILC2 cells within the engrafted organ.

Fucoxanthin Ameliorates Atopic Dermatitis Symptoms by Regulating Keratinocytes and Regulatory Innate Lymphoid Cells

“…ILC2 also contributes to the functions of mast cells [41,42]. Recent reports demonstrated that Il-10-secreting pulmonary ILC2 10 expresses GATA3 and produces Il-5 and Il-13 [14].…”

Group 2 Innate Lymphoid Cells in Respiratory Allergic Inflammation

“…Of note, ILC2s present in the skin can control mast cell (MC) activity by direct interaction (97). Conversely, MC are an important source of IL-33 in vivo , contributing to ILC2 activation and type 2 immune response in disease models of multiple sclerosis (85), and helminth infection (98), a MC-ILC2 crosstalk also occurs in the lung (99). It is not yet fully understood how cutaneous antigen exposure could activate ILC2s but it is conceivable that dysregulation between MC and ILC2s could exacerbate the immune response during allergic airway inflammation and anaphylactic reaction.…”

Multi-cellular and multi-molecular immune interactions in the transplantation tolerance and rejection

“…33 Mast cells act as antigen-presenting cells, express several co-stimulatory molecules and produce wide varieties of both anti-inflammatory and proinflammatory molecules. 34,35 Mast cell degranulation breaks the peripheral tolerance in skin and cardiac allograft. 36 Mast cells are also known to produce several molecules such as histamine, fibroblast growth factor-2 (FGF-2), TGF-α, chymase and cathepsin G. These molecules contribute to the histological changes in the graft and fibrosis.…”