This is not a prison break scheme. I was shocked to hear on BBC that researchers published a study, in the journal Genetic Vaccines and Therapy, about a new route for the delivery of specifically DNA virus vaccinations. Using the vibrating needle, normally used in tattoo parlors, they first experimented with mice & found a 16-fold increase in the humoral & cell-mediated antibody response elicited by these animals compared to the intramuscular injection. The needle implants small DNA fragments into the epidermis, which triggers a non-specific immune response believed to be the reason for the higher antibody levels found despite the lower dose of DNA used.

Flattering as it sounds, a lot of skeptics doubt that it would become a complete replacement of the conventional routes currently in use. It does not come without a cheap price either. Many tattoo lovers loathe the accompanying pain. Plus, potential users won’t be getting a tattoo in the process either because the needle won’t be loaded with ink.

Just truly amazed at whoever first comes up with such ideas and tries putting them to the test.

Image Credit: Enquirer

Tags: DNA, Gene Therapy, immune response, tattoo, vaccine

Despite great advances in cancer therapy, conventional therapies are still implementing drawbacks and dilemmas that drives cancer research to consider other strategies to overcome the drawbacks implicated by conventional cancer therapy. The  cancer treatment using  anticancer agents possesses many adverse events related to bone marrow suppression and death  of other rapidly proliferating cells is resulting from the either of the two following reasons:

• The narrow therapeutic index of anticancer agents that is in many cases hard to adjust with the inter-individual Pharmacokinetic &/or pharmacogenetic variation among  cancer patients.
• The lack of specificity in most of anticancer agents systemically administered where anticancer agents kill both tumor cells and healthy cells.

Both of the above facts driven cancer therapy research in to many different aspects in the hope of optimizing the therapy & providing new techniques to get over the drawbacks of conventional therapy; The pharmacokinetics & /or pharmacogenetics, gene therapy  in addition to the targeting therapy including the nanotherapy.

Professor Mostafa El Sayed  was awarded the 2007 US National Medal of Science for his huge contribution in the field of nanotherapy in cancer  as a molecular targeting approach that overcomes side effects of conventional cancer therapy. The idea lies in two main aspects: The first is molecular targeting & the second is photothermal destruction of malignant cells. The technique encompasses injecting gold nanoparticles conjugated with anti- Epidermal Growth Factor Receptor “anti -EGFR”  monoclonal antibody , where the anti-EGFR is responsible for the the specific targeting which is molecularly based on the fact that epithelial carcinoma cells, particularly over-expresses “EGFR”. Regarding the tumor cidal effect it is mainly dependent on the  photothermal destruction which is the role of the laser beam & gold nanoparticles, where particular nano size of gold makes it able to absorb light in Near Infra Red Region , which is the region where optical penetration is optimal &  scatter laser beam and convert the light energy to thermal energy that is able to damage cell membrane and release the digestive enzymes and hence the death of cancer cells.

Image credit: www.gatech.edu

The choice of the laser light is a matter of  the cancer location , where in case of cancer under the skin,  Near Infra Red “NIR” laser light is recommended for its larger penetration depth. Gold particles are especially used because  they are easily bioconjugated & they served as photoabsorbers due to overlap of absorption band of their specific nanosize with with argon laser beam. The gold nanoparticles are having a silica core and a gold shell & their absorption in the NIR is tuned by adjusting gold layer thickness as well as the size of silica core.

The pioneering success of the technique has been proved effective upon accumulation of Anti-EGFR antibody conjugated gold nanoparticles selectively in carcinoma cells and survival of benign cells as demonstrated by microscopic pictures of both  benign & cancer cells as follows:

Gold nanoparticles are concentrated in cancer cells. “Pic 1”
Image credit: www.gatech.edu

Gold nanoparticles are not retained in benign cells. “Pic 2”
Image credit: www.gatech.edu

References:

• Ivan H. El Sayed, Xiaohua Huang, Mostafa A. El Sayed, ” Selective laser Photo-thermal therapy of epithelial carcinoma  using anti-EGFR antibody conjugated gold nanoparticles”, Cancer Letters 239 (2006) 129-135.
• Erin B. Dickerson, Erick C. Dreaden, Xiaohua Huang, Ivan H. El Sayed,Hunghao Chu, Sujatha Pushpanketh, John F. Mcdonald, Mostafa A. El Sayed, ” Gold nano assiated near-infrared Plasmonic Phototheramal Therapy (PPTT) of squamos cell carcinoma in mice”, Cancer Letters 269 ( 2008) 57- 66.

Tags: adverse events, anticancer, argon laser, bone marrow suppression, cancer, Epithelial Carcinoma, Gene Therapy, laser, Molecular targetting, monoclonal antibody, nanotherapy, narrow therapeutic index, Pharmackinetic, pharmacogenetic, Photo-Thermal Destruction, Professor Mostafa El Sayed

May 2008

Gene Therapy: Seeing the future with new eyes

For the first time, doctors have used gene therapy to restore some vision in children with a congenital vision problem called Leber Congenital Amaurosis or “LCA” caused by a faulty gene (RPE65) 

The procedure involved the injection of a solution containing the normal gene, carried on an adenovirus vector, into the back of the retina of the affected eye.

In Britain, three patients have been treated with this experimental therapy. One has significantly improved & has been video-taped prior to the treatment & then six months later, traveling through a maze. Video HERE

The other two patients, aged 17 and 23, did not report any improvement, but did not suffer any side effects either.

Similarly, a US research team experimented on three patients, one aged 19 and two aged 26, and are reported to have improved vision as measured by standard eye tests, however, one developed a hole in the retina, thought to be due to the surgery itself.

This is a very significant milestone especially because researchers have been dealing with patients in the late stages of the disease & more hope is yet to come in those with the less-advanced form.

This is only the second time gene therapy has been proved successful in humans, after trials showed it was effective in the rare inherited disorder SCID (Severe Combined Immune Deficiency)

Tags: Gene Therapy, retina, vision