In a preclinical transgenic model of Alzheimer’s disease, these cells also demonstrated long-term beneficial effects following transplantation, suggesting a significant paracrine role in re-instructing the host compromised immune system and secreting amyloid beta-degrading enzymes and high levels of TGF-β and matrix metallopeptidase 9 (MMP9) [28]. Here, MMP9 is linked to Alzheimer disease.