Donor-derived exosomes: key in lung allograft rejection?

In a recent publication, Gunasekaran and colleagues conducted a case-control observational study in patients who underwent bilateral lung transplantation (LTx), determining whether exosomes are generated during allograft rejection and define their origin and antigenic phenotype (1). LTx is the sole effective treatment to save the life for patients with end-stage lung disorders (2). One of the major drawbacks for the clinical outcome of LTx is allograft rejection by acute rejection (AR) or bronchiolitis obliterans syndrome (BOS) (2). A link between autoimmunity and immune responses to tissue restricted self-antigens (SAgs) such as K-alpha-1-tubulin (K-α1T) and Collagen V (Col-V) with acute or chronic lung allograft rejection has been proposed (3,4). However, the mechanisms underlying the evolution of acute or chronic lung rejection are poorly understood.