HSCT cures ADA2 deficiency

In this issue of Blood, Hashem et al report a remarkable therapeutic result: all facets of the diverse spectrum of the rare disease adenosine deaminase 2 (ADA2) deficiency, which range from vasculopathy including stroke to severe anemia and immunodeficiency, can be corrected by hematopoietic stem cell transplantation (HSCT).(1) What unites these diverse manifestations is the deregulation of the innate immune system. The rapidly expanding knowledge is gained from detailed analysis of the innate immune system and the genes that regulate the function of myeloid cells, macrophages, and antigen-presenting cells. This knowledge forms the basis for understanding many diseases.(2-4) Thus, hyperinflammation is found in disorders including cancer, neurological diseases, bowel diseases, rheumatoid diseases, and vasculitis, with a strong contribution of the innate immune system to disease initiation and progression.