Why Autoimmune Diseases Cause the Body to Attack Itself

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A new study published in the journal Cell explores the cellular "runaway train" that allows lupus and other autoimmune diseases to spread throughout the body.

Autoimmune disease is exactly what it sounds like—the body mistakenly fighting itself. This attack may take the form of type 1 diabetes, celiac disease, rheumatoid arthritis, inflammatory bowel disease, or lupus, among others. But what begins as a local problem often eventually goes global.

"Once your body's tolerance for its own tissues is lost, the chain reaction is like a runaway train," co-author Michael Carroll of Boston Children's Hospital and Harvard Medical School said in a statement.

The disease tricks the body into expanding its attack. In a process called epitope spreading, autoantibodies target more and more tissues and organ systems over time, causing new symptoms like joint pain, kidney damage, and severe skin rashes.

To find out how it happens, Carroll and his colleagues zoomed way, way in to examine the progression of lupus in the tissues of lab mice.

"Lupus is known as 'the great imitator' because the disease can have so many different clinical presentations resembling other common conditions," first author Søren Degn, of Boston Children's Hospital and Aarhus University, said in the statement.

"It's a multiorgan disease with a plethora of potential antigenic targets, tissues affected and 'immune players' involved. Lupus is considered a prototypic autoimmune disease, which is why it's so interesting to study."

The researchers used what's called a confetti technique, marking different types of diseased B cells with different colors, then watching the colored dots multiply, scatter, and spread.

Graphic of multicolored autoantibodies
Immune cells called B cells battle each other to produce the best antibody. Here, green represents the B cells that produce the "winning" antibody and stamp out competing B cells (other colors).
Carroll Lab/Boston Children's Hospital

The confetti images revealed a microscopic soap opera, as the different colors struggled for dominance and power. As time went on, the makeup of the confetti shifted. One color, or cell type, had won.

Those toxic cells then began converting their neighbors.

"Over time, the B cells that initially produce the 'winning' autoantibodies begin to recruit other B cells to produce additional damaging autoantibodies—just as ripples spread out when a single pebble is dropped into water," Degn said.

The researchers were surprised but excited by their results, which they believe could someday lead to new types of treatment.

"Blocking germinal centers in the midst of an autoimmune response could potentially block the epitope-spreading process," Carroll said. "If you could stop the adaptive immune system for a transient amount of time, it might allow the body to reset its immune responses and shut off the autoreactivity."

Hundreds of 17th-Century Case Notes of Bizarre Medical Remedies Have Been Published Online

Illustrated portrait of Simon Forman.
Illustrated portrait of Simon Forman.
Hulton Archive/Getty Images

As medical texts, the writings of Simon Forman and Richard Napier aren't very useful. The so-called "doctors," regarded as celebrities in 16th- and 17th-century England, prescribed such treatments as nursing puppies and wearing dead pigeons as shoes. But as bizarre pieces of history, the 80,000 case notes the two quacks left behind are fascinating. The BBC reports that 500 of them have now been digitized and published online.

Forman and Napier were active in the English medical scene from the 1590s to the 1630s. They treated countless patients with remedies that straddled the line between medicine and mysticism, and their body of work is considered one of the largest known historical medical collections available for study today. After transcribing the hard-to-read notes and translating them into accessible English, a team of researchers at Cambridge University has succeeded in digitizing a fraction of the records.

By visiting the project's website, you can browse Forman and Napier's "cures" for venereal disease ("a plate of lead," "Venice turpentine," and blood-letting), pox (a mixture of roses, violets, boiled crabs, and deer dung), and breastfeeding problems (using suckling puppies to get the milk flowing). Conditions that aren't covered in today's medical classes, such as witchcraft, spiritual possession, and "chastity diseases," are also addressed in the notes.

All 500 digitized case notes are now available to view for free. And in case you thought horrible medical diagnoses were left in the 17th century, here some more terrifying remedies from relatively recent history.

[h/t BBC]

Now Ear This: A New App Can Detect a Child's Ear Infection

iStock.com/Techin24
iStock.com/Techin24

Generally speaking, using an internet connection to diagnose a medical condition is rarely recommended. But technology is getting better at outpacing skepticism over handheld devices guiding decisions and suggesting treatment relating to health care. The most recent example is an app that promises to identify one of the key symptoms of ear infections in kids.

The Associated Press reports that researchers at the University of Washington are close to finalizing an app that would allow a parent to assess whether or not their child has an ear infection using their phone, some paper, and some soft noises. A small piece of paper is folded into a funnel shape and inserted into the ear canal to focus the app's sounds (which resemble bird chirps) toward the child’s ear. The app measures sound waves bouncing off the eardrum. If pus or fluid is present, the sound waves will be altered, indicating a possible infection. The parent would then receive a text from the app notifying them of the presence of buildup in the middle ear.

The University of Washington tested the efficacy of the app by evaluating roughly 50 patients scheduled to undergo ear surgery at Seattle Children’s Hospital. The app was able to identify fluid in patients' ears about 85 percent of the time. That’s roughly as well as traditional exams, which involve visual identification as well as specialized acoustic devices.

While the system looks promising, not all cases of fluid in the ear are the result of infections or require medical attention. Parents would need to evaluate other symptoms, such as fever, if they intend to use the app to decide whether or not to seek medical attention. It may prove most beneficial in children with persistent fluid accumulation, a condition that needs to be monitored over the course of months when deciding whether a drain tube needs to be placed. Checking for fluid at home would save both time and money compared to repeated visits to a physician.

The app does not yet have Food and Drug Administration (FDA) approval and there is no timetable for when it might be commercially available. If it passes muster, it would join a number of FDA-approved “smart” medical diagnostic tools, including the AliveKor CardiaBand for the Apple Watch, which conducts EKG monitoring for heart irregularities.

[h/t WGRZ]

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