Researchers at the University at Buffalo (UB) have developed a novel technology using quantum dots that is expected to have major implications for research and treatment of tuberculosis, as well as other inflammatory lung diseases.
A paper appearing online in Nanomedicine: Nanotechnology, Biology and Medicine as an article-in-press describes specific delivery of a chemotherapeutic drug to specific cells in the lung, particularly the alveolar white cell, without causing acute inflammation.
Quantum dots are tiny semiconductor particles generally no larger than 10 nm that can be made to fluoresce in different colors, depending on their size. Scientists are interested in quantum dots because they are a superb carrier and last much longer than conventional dyes used to tag molecules, which usually stop emitting light in seconds.
In this research, quantum dots were linked with doxorubicin, an anti-cancer chemotherapy drug, to target specific lung cells, known as alveolar macrophages (aMO), which play a critical role in the pathogenesis of various inflammatory lung injuries.
"The aMO is the sentinel cell involved in directing the host innate and adaptive immune responses involved in infectious and non-infectious lung diseases such as COPD," notes Krishnan V. Chakravarthy, Ph.D., a research fellow in the UB School of Medicine and Biomedical Sciences joint MD/Ph.D. program and lead author on the paper. "The aMO's central role in response to environmental influences makes these cells an ideal candidate for targeted drug delivery to modulate the immune/inflammatory response."
To test the ability of linked quantum dot-doxorubicin (QD-DOX) to decrease lung inflammation, the researchers delivered QD-DOX or doxorubicin alone to rats and mice and assessed the damage to the lung. Doxorubicin, a frequently used cancer drug, is known to cause a variety of damaging immune responses in cancer patients.
Results showed that QD-DOX increased uptake of the drug compared with doxorubicin alone, and did not cause as significant a pro-inflammatory response as doxorubicin alone. The researchers also demonstrated that the drug is released from the QD-DOX formulation once it is delivered into the targeted cell and still retains its bioactivity.
"Based on these results, we believe that linking quantum dots with therapeutic drugs may have tremendous potential for diagnosis and treatment of lung injury compared to other nanoparticle formulations, and should be further developed for lung pharmacotherapy applications," says Chakravarthy.
Additional authors on the paper, all from UB, are Bruce A. Davidson, Ph.D.; Jadwiga D. Helsinki; Hong Ding, Ph.D.; Wing-Cheung Law; Ken-Tye Yong, Ph.D.; Paras N. Prasad, Ph.D.; and Paul Knight, MD, Ph.D.
Source: University at Buffalo
Posted by Lee Mather
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