Dendritic cells in liver protect against acetaminophen toxicity

September 1, 2011

NYU School of Medicine researchers have discovered that dendritic cells in the liver have a protective role against the toxicity of acetaminophen, the widely used over-the-counter pain reliever and fever reducer for adults and children. The study's findings are published in the September issue of the journal Hepatology.

The is the organ that plays a central role in transforming and filtering chemicals from the body. High-doses of acetaminophen can cause hepatotoxicity, chemical driven . In fact, accidental and intentional acetaminophen overdose are the most frequent causes of acute liver failure (ALF) in the United States. Acetaminophen related liver failure by intentional or accidental overdose causes 56,000 emergency room visits, 2,600 hospital visits and 450 deaths annually. As a result, this year the FDA mandated drug manufacturers to start limiting the amount of acetaminophen in products and is currently exploring adding safer dosing instructions to children's acetaminophen products.

In the new study, researchers found an abundance of dendritic cells in the liver can protect the organ from acetaminophen damage while low levels of dendritic cells in the liver are associated with exacerbated liver damage, and tissue death, known as centrilobular hepatic necrosis, and from acetaminophen.

"Our research results confirm a central role for dendritic cells and their powerful regulation of acetaminophen's toxicity," said George Miller, MD, senior author of study and assistant professor, Departments of Surgery and at NYU Langone Medical Center. "High levels of dendritic cells have a novel, critical and innate protective role in acetaminophen hepatotoxicity. We now have greater insight into the liver's tolerance of acetaminophen toxicity and dendritic cell regulation of these toxins."

In the study, researchers used acetaminophen-induced hepatic injured mice models to closely examine the protective role of dendritic cells. Dendritic cells are the main antigens in the liver that trigger an immune response and control the liver's tolerance to high doses of invading toxins like acetaminophen. In the experiment all mice were injected with acetaminophen but some mice models were first depleted of dendritic liver cells using a diphtheria toxin while others had their dendritic cell levels bolstered with Flt3L, a protein in the blood previously shown to increase proliferation of dendritic cell levels.

Researchers discovered dendritic cell depletion exacerbates acetaminophen's damage to the liver. The acetaminophen treated mice with depleted dendritic cells had more extensive liver cell and compared to other mice. Also, these mice died within 48 hours of acetaminophen challenge- whereas death was rare in other mice without dendritic cell depletion. In addition, the study shows dendritic cell expansion successfully diminished the hepatotoxic effects of acetaminophen protecting the liver from damage.

"Understanding the regulatory role of dendritic cells is an important step in the development of immune-therapy for induced liver injury," said Dr. Miller, a member of the NYU Cancer Institute. "Advanced studies are warranted to investigate further the protective role of in humans and their use as a possible new therapeutic target for liver failure prevention in the future."

Related Stories

Recommended for you

We've all got a blind spot, but it can be shrunk

August 31, 2015

You've probably never noticed, but the human eye includes an unavoidable blind spot. That's because the optic nerve that sends visual signals to the brain must pass through the retina, which creates a hole in that light-sensitive ...

Biologists identify mechanisms of embryonic wound repair

August 31, 2015

It's like something out of a science-fiction movie - time-lapse photography showing how wounds in embryos of fruit flies heal themselves. The images are not only real; they shed light on ways to improve wound recovery in ...

New 'Tissue Velcro' could help repair damaged hearts

August 28, 2015

Engineers at the University of Toronto just made assembling functional heart tissue as easy as fastening your shoes. The team has created a biocompatible scaffold that allows sheets of beating heart cells to snap together ...

Fertilization discovery: Do sperm wield tiny harpoons?

August 26, 2015

Could the sperm harpoon the egg to facilitate fertilization? That's the intriguing possibility raised by the University of Virginia School of Medicine's discovery that a protein within the head of the sperm forms spiky filaments, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.