Abstract
Graft-versus-host disease (GVHD) is a disabling complication after allogeneic hematopoietic stem cell transplantation (HSCT) and negatively impacts patients’ quality of life. GVHD is classified into 2 forms according to clinical manifestations. Acute GVHD (aGVHD) typically affects the skin, gastrointestinal tract, and liver, whereas chronic GVHD occurs systemically and shows diverse manifestations similar to autoimmune diseases such as eosinophilic fasciitis, scleroderma-like skin disease. GVHD is induced by complicated pathological crosstalk between immune cells of the host and donor and involves various signaling pathways such as purinergic signaling. Although the past several decades have seen significant progress in the understanding of mechanisms of GVHD and several drugs have been approved by FDA for the prevention and treatment of GVHD, there is still vast scope for improvement in the therapy for GVHD. Thus, new drugs for GVHD will need to be developed. Towards this goal, this chapter succinctly summarises the pathogenic process of GVHD and emerging GVHD treatments in order to provide some insights into the mechanisms of GVHD and facilitate the development of novel drugs.