Zinc finger nucleases (ZFNs) are engineered DNA-binding proteins with remarkable, highly programmable sequence-specificity. However, their widespread use has been slowed by licensing issues and the technical difficulty of synthesising new variants. A new platform, CoDA (context-dependent assembly), promises to make these exceptionally useful tools available to a far greater number of researchers.
One of our priorities at the SENS Foundation Research Center has been to overcome the limitations of our ability to test potential A2E-degrading enzymes caused by a restricted supply of the target molecule (A2E). We have now successfully synthesized A2E, purifying it by flash chromatography and HPLC, and confirming it to be identical to that produced in Janet Sparrow's laboratory through different analytical tests.
Toward Full Pluripotency of Reprogrammed Cells -- And Cautionary Tale About Abandoning the 'Gold Standard'Posted by Michael Rae on December 09, 2010 | Chief Science Officer's Team
Induced pluripotent stem cells (iPSCs) are among the most exciting recent developments in biomedicine, overcoming immunological and ethical issues associated with the use of embryonic stem cells (ESCs). However, reasonable doubt remains regarding whether iPSCs do in fact have the full biological and therapeutic potential of ESCs. Work at the Harvard Stem Cell Institute recently produced the first "all-iPSC" live mice, a milestone on the road to establishing full equivalence between the two methods.
Resveratrol, a polyphenol famously found in wine, has previously been shown to extend lifespan in some naturally unhealthy rodent strains - but unfortunately does not show the same benefits in healthy, naturally long-lived mice. Meanwhile rapamycin, an immunosuppressant drug, has now become the first substance confirmed to at least moderately extend maximum lifespan in healthy mice.
The clearance of beta-amyloid (Abeta) and other protein aggregates by immunotherapy is a key rejuvenation biotechnology to restore youthful function to aging brains, especially those with Alzheimer's disease (AD) and other neurodegenerative disorders. Initial trials using anti-Abeta vaccines have demonstrated concomitant reductions in early-stage tau aggregates, but not in mature neurofibrillary tangles, suggesting that such vaccines would be optimally deployed much earlier in the disease process - or in combination with anti-tau vaccines.
SENS Foundation's CSO, Dr Aubrey de Grey, was first featured in Wired magazine in 2008, shortly before the Methuselah Foundation's initial USA-based conferences. Two years on, he's now returned in a more candid and detailed interview, discussing how the tactics involved in bringing rejuvenation biotechnologies to the attention of mainstream science have evolved and begun to bear fruit.
In September 2007 SENS Foundation's Chief Science Officer, Dr Aubrey de Grey, together with co-author Michael Rae published Ending Aging - an accessible description of the SENS platform. We're delighted to now be able to make the afterword to the paperback edition, summarising progress since the initial hardback publication, available for free download.
Neurofibrillary tangles (NFTs - cytoplasmic inclusions composed of abnormal species of tau protein) accumulate in the aging brain, particularly in neurodegenerative disease, where they are closely associated with areas of neuronal death. The urgency of tackling tau accumulation in particular has become more apparent after recent studies revealed that clearance of beta-amyloid alone achieves only moderate clinical benefits, with continued pathology attributed in particular to persistent NFTs.
The well-known beta-amyloid protein that plays a major role in Alzheimer's disease is only one of those which accumulate in aging bodies. Cardiac amyloidoses, caused by aggregation of the proteins transthyretin and atrial natriuretic peptide, are already the dominant cause of death in supercentenarians (those 110 years of age or older) and are expected to become much more widespread in an increasingly aged general population and as improved treatment options become available for other age-related diseases. SENS Research Foundation has recently launched a project exploring the use of catalytic antibodies - which actively degrade their target, rather than merely binding to it - to remove such aggregates.
A technique combining the sequence-specific DNA-cleaving property of zinc finger nucleases (ZFNs) and the localisation function of transcription activator-like effectors (TALEs), creating a new class of composite proteins called TALE nucleases (TALENs), shows considerable promise for expanding the range of genomic sites susceptible to precision engineering.
Comprehensive rejuvenation must include the removal of extracellular protein aggregates from aging tissues. Immunotherapy - in which the immune system is encouraged to recognise and clear a particular protein - is the most clinically-advanced biotechnology for this purpose, but has some limitations. Notably, rapid immune clearance of a large volume of protein can cause severe inflammatory side-effects; also, efficacy depends on the patient's response to vaccination, which declines dramatically in the elderly patients most in need of therapy. A new approach using catalytic antibodies that directly degrade the amyloid proteins may overcome these problems.
Mutations to the mitochondrial DNA (mtDNA) are thought to be a major source of aging-related increases in oxidative stress. The candidate SENS therapy, allotopic expression, involves the production of mitochondrial proteins from the nuclear DNA and their import into the organelle. An alternative mechanism where RNA, rather than protein, is imported is now providing another avenue for research.