Nanoparticles Targeted By Immune System

Nanoparticles meant for drug delivery, pacemakers or artificial joints are targeted by our immune system which identifies and destroys foreign objects, be they bugs or viruses.

Now, researchers at the University of Pennsylvania School of Engineering and Applied Science and its Institute for Translational Medicine and Therapeutics have figured out a way to provide a "passport" for such therapeutic devices to sneak in past the body's security system.

Nanoparticles can Damage DNA, Increase Cancer Risk
Tissue studies indicate that nanoparticles, engineered materials about a billionth of a meter in size, could damage DNA and lead to cancer

In 2008, the group led by Dennis Discher, professor at Pennsylvania University, showed that the human protein CD47 is found on almost all mammalian cell membranes.

Like a border guard inspecting a passport, it tells the macrophage (white blood cells) that the cell or an object isn't an invader and should be allowed to proceed, the journal Science reports.

"There may be other molecules that help quell the macrophage response," Discher said. "But human CD47 is clearly one that says, 'Don't eat me'."

Aerosolized Nanoparticles Could Help Improve Drug Delivery
A novel method of drug delivery using aerosolised nanoparticles may assist in improving drug delivery and enhancing patient comfort.

"From your body's perspective... an arrowhead a thousand years ago and a pacemaker today are treated the same -- as a foreign invader," said Pia Rodriguez, a graduate student working under Discher, according to a Penn statement.

"We'd really like things like pacemakers, sutures and drug-delivery vehicles to not cause an inflammatory response from the innate immune system," Rodriguex added.

Biochemistry of Inflammation Detected By Nanoparticles
From infection to neurodegeneration, inflammation is the hallmark of many human diseases.

The innate immune system attacks foreign bodies in a general way. Unlike the learned response of the adaptive immune system, which includes the targeted antibodies that are formed after a vaccination, the innate immune system tries to destroy everything it doesn't recognize as being part of the body.

Drug-delivery nanoparticles naturally trigger this response, so researchers' earlier attempts to circumvent it involved coating the particles with polymer "brushes".

Scientists To Study Effect Of Nanoparticles On Liver
University of Edinburgh researchers will study the effect of tiny nanoparticles on the health of the liver.

Source-IANS