Saturday, 17 March 2012

Glow in the Dark Cats Furthering AIDs Research

Lochlan Overton - 42905011
In September 2011, the Mayo Clinic of Rochester Minnesota, U.S.A., made an outstanding development in regards to AIDs research. The scientific team, consisting of physicians, veterinarians, virologists and gene therapy researchers developed a “genome-based immunisation strategy” that may lead to dramatic reductions in the contraction and spreading of AIDs both in the human, and the feline worlds. (Mayo Clinic, 2011).

Molecular biologist Dr. Eric Poeschla, tells of how cats can become infected with FIV (Feline Immunodeficiency Virus), which is the AIDs inducing equivalent to HIV in humans (Mayo Clinic, 2011). AIDs destroys the immune system of the host, leaving the host defenceless against other harmful virus invasions, such as the flu and pneumonia (AIDS Action Council of the ACT, n.d.).

Both humans and felines have natural proteins that defend against virus invasions, these are referred to as ‘restriction factors’. Unfortunately, they are ineffective against HIV and FIV and as a consequence both strands of AIDs have resulted in the death of millions. Poeschla proclaims that this study will “benefit both human and feline health” (Mayo Clinic, 2011).

Figure 2: Rhesus Macaque in Tree, (Arkive, n.d.)
Through research the scientists discovered a restriction factor, found in Rhesus Macaque (Figure 2 beside), that is effective against FIV. Utilising the technique of ‘Gamete-targeted Lentiviral Transgenesis’, the team extracted the restriction factor, called TRIMCyp, and inserted it into the feline ova genome, prior to fertilisation by sperm. (Mayo Clinic, 2011).

Along with the TRIMCyp, a Green Fluorescent Protein (GFP) common in jellyfish was also added. Poeschla explains that this results in the transgenic felines fluorescing green when exposed to certain frequencies of light
 (Mayo Clinic, 2011). 

Geneticists and scientists often choose to also add the GFP as it can be “attached to other proteins” (Combs, C 2009).  This then means that specific proteins can be “marked” with a GFP and provide scientists with an easy, non-invasive way to identify the modified gene’s growth, dispersal and inheritability (Combs, C 2009), as demonstrated in Figure 3 below.

Figure 3: A transgenic kitten viewed under special frequency light, sitting next to a non-modified feline, (Jha, A 2011)

Thus far experiments have been promising and have shown that cells taken from the transgenic felines are resistant to the FIV virus. However, the artificial environment on a petri-dish is no substitute for direct testing of the transgenic cats’ resistance (British Broadcasting Corporation, 2011).

The research team at Mayo Clinic tell that this “method of inserting genes into the feline genome is highly efficient”. One key reason for this is that the “inserted genes remain active in successive generations” (Mayo Clinic, 2011). This meaning that the offspring of the transgenic felines have cells that produce TRIMCyp (and GFP) proteins. The team also tell that “this specific genome modification will not be used directly for treating people with HIV or cats with FIV” but it will instead “help medical and veterinary researchers understand how restriction factors can be used to advance gene therapy for AIDS” (Mayo Clinic, 2011).

As stated above, this advancement in genetics is not a direct cure for HIV or FIV AIDs. However, it has proven that FIV resistant organisms can be created and that these favourable genes and proteins can be successfully inherited by offspring. Only with time will we know of the remarkable developments made as a result of this advancement in genetics.
Reference List:

AIDS Action Council of the ACT, n.d., Facts about HIV and AIDS, viewed 16 March 2012,
http://www.aidsaction.org.au/content/hiv_sti_health/factsHIVAIDS.php

Arkive, n.d., Rhesus Macaque (Macaca Mulatta), viewed 11 March 2012, http://www.arkive.org/rhesus-macaque/macaca-mulatta/#text=Biology

Biology Online, 2005, Transgenic, viewed 11 March 2012,
http://www.biology-online.org/dictionary/Transgenic

British Broadcasting Corporation, 2011, Glowing cats shed light on Aids, viewed 16 March 2012, http://www.bbc.co.uk/news/science-environment-14882008

Combs, C 2009, Glowing Animals: Beasts Shining for Science, National Geographic, viewed 10 March 2012, http://news.nationalgeographic.com/news/2009/05/photogalleries/glowing-animal-pictures/

Jha, A 2011, Glow cat: fluorescent green felines could help study of HIV, The Guardian, viewed 11 March 2012, http://www.guardian.co.uk/science/2011/sep/11/genetically-modified-glowing-cats

Mayo Clinic, 2011, New Technique Gives Cats Protection Genes, viewed 9 March 2012, http://www.mayoclinic.org/news2011-rst/6434.html

Science News Line, 2011, Mayo Clinic Teams with Glowing Cats Against AIDS, Other Diseases, viewed 11 March 2012, http://www.sciencenewsline.com/biology/2011091209160004.html

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