I learned about this from another cruelty-free blogger, Raffaella, (who has an amazing blog!  You should go check it out!).  Apparently, there is a new non-animal method of studying injury-healing.  (You can also now subscribe to Raffaella’s blog even if you don’t speak Italian — the new Google Reader automatically translates it from Italian straight into English!)

Basically, the Dr. Hadwen Trust, (an amazing trust dedicated to funding non-animal tests — seeing how it’s the holidays, if you’d like to donate money to a charity — it sounds like a GREAT charity to donate to — here’s their donating information), funded some scientists in Australia and Cardiff (Z Upton, L Cuttle, A Noble et al) who, using skin donated by patients undergoing surgical procedures, cause the skin to grow in sheets in petri dishes, and then study the differences between skin taken from healthy skin cells versus skin taken from patients with chronic venous leg ulcers, and compare the gene expression between those. (To my very limited understanding.)

This is FANTASTIC for three reasons.  First, harming layers of tissue in petri dishes instead of live skin on rats is much less morally objectionable.  Skin cells in petri dishes have no nervous systems!  They cannot feel pain or fear!  Second, results can be found much more quickly with skin cells in petri dishes rather than with live rats — scientists can run hundreds of tests a day using skin cells in petri dishes, whereas only thirty or so tests can be run once a month on (expensive bred-without-immune-system) live rats.  Third, rat skin, which is the traditional skin used to look at differences between injured skin and noninjured skin — is completely different from human skin.  Extrapolating from rat skin to human skin is futile.  Rodents are ‘loose-skinned’ — they heal wounds by “contracture,” whereas human skin heals by “re-epithelialisation.”  Human skin also isn’t covered by a fur coat, which complicates wound healing, and lab rats are typically “sacrificed” when they are adolescents and relatively healthy, whereas many of the people for whom wound-healing is a problem are elderly and/or diabetic, both of which can cause severe wound-healing complications.  Thus, using rats to study human wound-healing is fundamentally flawed — using human skin grown in petri dishes is far more scientifically valid.

Anyway, I’m really excited by this!  Non-animal methods just get better every day!

(And because I like to give credit where credit is due, I’d like to thank the scientists Z Upton, L Cuttle, A Noble et al, and the Dr. Hadwen Trust for creating such a compassionate technique!)

Here’s the original article from the Dr. Hadwen Trust:

3 October 2008

Advances in non-animal wound healing research

In vitro methods have been developed by researchers in Australia and Cardiff that could revolutionise wound healing research. Painful tests are often conducted on animals, commonly rodents, for wound healing studies because human skin equivalents have historically lacked the realistic properties required for effective research.

Now, however, researchers at Queensland’s University of Technology in Australia have made a complex 3-D model using skin donated by patients undergoing surgical procedures. The skin keratinocytes are isolated and grown as a skin substitute in vitro in an animal-product-free medium.

The researchers at Cardiff University were funded by the Dr Hadwen Trust from 2004-2007, and used human telomerase immortalised fibroblast cell lines developed from chronic venous leg ulcers and from patient-matched healthy tissues. They then studied the differences in gene expression between the damaged and healthy fibroblasts and found that these were maintained in the cell lines in culture.

The cells were transfected with a fluorescent protein linked to a chronic wound-marker gene. This allowed quantification of changes in fluorescence, and hence gene expression, over time. The technique therefore represents a promising new way to study wound healing without painful experiments on animals.

Methods based on human skin cells are essential to advancing our understanding in wound healing research because human skin and rodent skin heal in different ways. Rodents are ‘loose skinned’ and heal wounds by contracture, whereas human skin heals by re-epithelialisation. There are also differences in abundance of hair, and between wounds that are caused artificially in otherwise healthy animals and human wounds which are often problematic in diabetics and the elderly. All these differences make results from animals difficult to translate between species.

For further information see:

• www.scienceroom.org/wound-healing

• Upton Z, Cuttle L, Noble A et al (2008) Vitronectin: growth factor complexes hold potential as a wound therapy approach. Journal of Investigative Dermatology 128:1535-44

Categories : alternatives to animal testing