needs stem cells. Senescent cells can be removed by activating the immune system against them. Or they can be destroyed by gene therapy to introduce "suicide genes" that only kill senescent cells. Protein cross-linking can largely be reversed by drugs that break the links. But to break some of the cross-links we may need to develop enzymatic methods. Extracellular garbage (like amyloid) can be eliminated by vaccination that gets immune cells to "eat" the garbage. For intracellular junk we need to introduce new enzymes, possibly enzymes from soil bacteria, that can degrade the junk (lipofuscin) that our own natural enzymes cannot degrade. For mitochondrial mutations the plan is not to repair them but to prevent harm from the mutations by putting suitably modified copies of the mitochondrial genes into the cell nucleus by gene therapy. The mitochondrial DNA experiences a high degree of mutagenic damage because most free radicals are generated in the mitochondria. A copy of the mitochondrial DNA located in the nucleus will be better protected from free radicals, and there will be better DNA repair when damage occurs. All mitochondrial proteins would then be imported into the mitochondria. For cancer (the most lethal consequence of mutations) the strategy is to use gene therapy to delete the genes for telomerase and to eliminate telomerase-independent mechanisms of turning normal cells into "immortal" cancer cells. To compensate for the loss of telomerase in stem cells we would introduce new stem cells every decade or so. In 2009, Aubrey de Grey co-founded the SENS Foundation to expedite progress in the above-listed areas. Scientific journal Rejuvenation Research Editor: Aubrey de Grey. Publisher: Mary Ann Liebert, Inc. ISSN 1549-1684 – Published Bimonthly. See also Ageless Aging brain American Academy of Anti-Aging Medicine Anti-aging movement Biogerontology Biological immortality DNA repair DNA damage theory of aging Eternal youth Facial rejuvenation Fountain of Youth Hayflick Hayflick limit Immortality Indefinite lifespan iPSc as a result of radical rejuvenation Life extension Maximum life span Nanomedicine Photorejuvenation SAGE KE Senescence Shunamitism Telomere Telomerase Tissue engineering Therapeutic cloning References External links Life extension Transhumanism Concepts in alternative medicine Senescence