In addition, in the case of JAK2-driven MPN, it has been shown that in patients and in animal models, the disease is driven by a consistent reduction in the numbers of sympathetic nerve fibers, supporting Schwann cells, which regulates the HSC supporting functions of a subpopulation of nestin+ mesenchymal stem cells [48,49]. Here, JAK2 is linked to myeloproliferative neoplasm.