For decades, the cosmetic industry has perfected the use of tattoo machines to deliver permanent ink to precise locations on the human skin. Now, researchers have repurposed that technology to deliver drugs to cells tucked just under the skin, successfully treating cutaneous leishmaniasis in mice (1).
“This disease is typically very difficult to treat because the parasites infect macrophages under the skin,” said Anny Fortin of Dafra Pharma and McGill University, a lead author of the new work. “It’s hard for drugs to reach this location.” Currently, cutaneous leishmaniasis—which spreads via sand flies and mostly affects people in developing countries—is treated with painful injections of drugs into the diseased skin lesions.
Fortin was already working on packaging the anti-parasitic drug oleylphosphocholine (OIPC) into tiny liposomes for more effective uptake by the infected macrophages when she teamed with a colleague working with tattoo machines. Together, they formulated the liposomes for application through a tattoo device and started testing the treatment in mice with cutaneous leishmaniasis. In comparison with mice that received oral liposomes of OIPC, a topical treatment, or a control, animals treated with drugs delivered by tattoo had the largest decrease in lesion size. In fact, after 10 days of treatment, tattooing led to a complete—or near-complete—remission of disease in the mice.
“We were very surprised,” Fortin said. “But if you think about it now, the tattooing instrument is actually bringing the drug exactly to the location of the cells that are affected.”
After treatment, the tattoo device left behind no visible evidence since the needles had been loaded only with drugs, not ink. But Fortin said there’s still fine-tuning to do: the tattoo equipment is messy, often spilling droplets of its contents during injection, so measuring the precise dosage of drug delivered to the skin is tricky. And for tattooing to be considered a superior treatment to the current injections given for cutaneous leishmaniasis, Fortin would like to shorten the course of treatment.
“Right now, we’re giving this treatment by tattooing every day for 10 days,” Fortin said. “It would be better if we could do it, say, once a week for a month.” Her team is working to develop a slow-release drug that would make that possible.
For now, Fortin’s group is focused on using tattoo machines for treating cutaneous leishmaniasis, but she believes that in the future, drugs targeting other skin conditions, including skin cancer, might also benefit from this approach.
1. Shio, MT., Paquet, M., Martel, C., Bosschaerts, T. et al. (2014) Drug Delivery by Tatooing to Treat Cutaneous Leishmaniasis. Scientific Reports 4:4156 (doi: 10.1038/srep04156)