<qa>  What is HDC a non-bone marrow transplant treatment option for?High-dose cyclophosphamide HDC is a non-bone marrow transplant treatment option for those afflicted by severe, refractory immune-mediated illnesses by pathologic autoreactive lymphocytes. The goal of this therapy is to induce immunoablation without myeloablation: that is, to eradicate offending B and T cells responsible for the illness while sparing the pluripotent blood stem cell of any ill effect. Since 1966, multiple publications on numerous immune-mediated illnesses have shown HDC without stem-cell rescue to decrease disease activity and improve quality of life 