'Buffy coats': The 1% of blood that helps fight off disease

Seven things you might not know about blood

The red stuff currently pumping throughout your body is a type of connective tissue that is both a solid and a liquid. The liquid portion—plasma—acts as a carrier for the solid portion, which includes blood cells and their biological brethren. Your body is constantly refreshing its supply of blood, creating new cells to replace those that have expired or died. This article overviews some lesser-known facts about blood (and why it's not always red).

Blood clotting is critical to maintaining life, but dysfunctional clots can be fatal

Clotting is how our body stops bleeding in the event of an injury. Typically, platelets adhere to exposed tissue, becoming sticky and forming a plug. Chemical signals trigger the coagulation cascade, converting fibrinogen into fibrin threads that stabilize the plug. This prevents bleeding but can obstruct vessels if overactive or misplaced.

The inner life of a cell

White blood cells are responsible for protecting the human body from infection. This video uses biophysical data from Harvard researchers to accurately demonstrate what goes on inside one white blood cell as it works within the immune system.

How much your blood really costs

In the US, donating plasma twice a week can earn you $400 a month. But this system only works by targeting people who need the money most. Plasma clinics are placed in low-income zip codes, and frequent donation may increase health risks.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

How did segregation in the US affect blood donations?

When the US established its first nationwide network of blood banks in 1941 with the hopes of restoring the dwindling reserves of military members, it was quick to emphasize blood donated by Black Americans wouldn't coat the veins of white servicemen. Historians say this policy was meant to appease white Southerners who believed Black blood was inferior to their own.This policy was leaked to the press that same year.

Bears have evolved natural mechanisms to avoid blood clots while hibernating

Movement is essential to keeping blood from clotting, which raises the question of why animals such as hibernating bears don't suffer from clots despite going months lying still. New research suggesting that the animals may have evolved to have lower concentrations of a specific protein may explain this phenomenon.

What is the blood brain barrier?

Every blood vessel is lined with endothelial cells that act as filters between blood and the rest of the body. In the brain, these cells are tightly packed together to keep a close watch on what substances can access the vital organ. This protective measure poses an obstacle to drugmakers looking to deliver drugs to the well-defended brain for conditions like Alzheimer's. Watch a quick overview here.

The economics of horseshoe crab blood

Horseshoe crabs are older than dinosaurs and have survived five mass extinctions that wiped most life from the planet. But it's only now that their future as a species is in danger. This blood, worth about $60,000 per gallon, is hyper-sensitized to certain bacteria that are fatal to humans. This 17-minute podcast dives into humanity's pursuit of horseshoe crab blood, a "somewhat magical" mixture heavily relied on by the pharmaceutical industry.

What are 'antibodies'? Read this quick overview

Antibodies are protective proteins produced by your immune system. They attach to antigens (foreign substances) and remove them from your body. Understand this important element of the immune system with this quick overview.

Learn how monoclonal antibodies, which mimic the body's antibodies, can fight diseases like Ebola.

Buffett is known for being extremely generous with his fortune

So generous that in 2010 he pledged to donate 99% of his money. He said this money “can have a huge effect on the health and welfare of others.” This letter is Buffett’s philanthropic pledge, which details his commitment to giving and how luck and privilege helped him accumulate so much money.

A macrophage can eat 100 bacteria, on average, before it's exhausted

These specialized immune cells are first responders during inflammation, responding to a threat or injury and then performing other inflammatory response tasks, including summoning neutrophils to help attack invaders.

A vaccine against Epstein-Barr virus, researchers hypothesize, could potentially prevent MS

As many as a quarter of MS patients have antibodies in their blood that bind to both a central protein in Epstein-Barr virus and a protein made in the brain and spinal cord that—when attacked—leads to a breakdown of protective nerve fiber insulation. This suggests the immune system's primed to attack the nervous system after mounting a defense against Epstein-Barr.

Trials ongoing for a 99% accurate, AI-powered blood test

The UK's National Health Service has launched a trial for a blood test that can detect a dozen types of cancers with just ten drops of blood. An AI tool looks for genetic material known to be released by tumors, allowing for cancer detection before tumors are large enough to be imaged.

Larger animals like giraffes, elephants, and blue whales have developed a unique defense against cancer, a phenomenon known as Peto's Paradox

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

Women typically have more robust immune responses than men

This difference helps women better combat infectious diseases, but this more turbo-charged response may also make women more vulnerable to autoimmune diseases by potentially priming their immune systems to overreact to their own cells and tissues and label them as invaders that must be destroyed. Roughly 80% of American women have autoimmune conditions.

Low cell division rates in heart cells make heart cancer particularly rare

The heart's location in the chest also offers protection from external cancer-causing factors. The disease affects about 3 in every 10,000 people, though most cases arise from metastasis from other body parts.

Read a deep dive on the 'all-purpose healing' peptide BPC-157.

Tattoos remain visible on your skin thanks to immune cells called macrophages

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

Dolly Parton produced the original 'Buffy the Vampire Slayer' movie

Parton’s Sandollar Entertainment company was responsible for the 1992 film, which eventually led to the television series of the same name—a pop culture sensation that inspired spin-offs and a devoted fanbase. Although Parton was not listed as a producer for the show, some believe showrunner Joss Whedon paid homage to her by making the titular character’s birthday the same as Parton’s.

Bullion is either gold or silver that has at least 99.5% or 99.9% purity, respectively

It’s typically kept in the form of bars or ingots. Governments and central banks often keep bullion reserves on hand; they can use it as a hedge against inflation. One can invest in bullion via ETFs, among other financial vehicles.

BPC-157 stands for Body Protection Compound-157

Listen to this primer on the peptide BPC-157, which is composed of 15 amino acids. This clinician describes how it's made synthetically, based on a substance found naturally in the human gut and discusses the limited research on the product.

How is immunotherapy used to fight cancer?

The Dana-Farber Cancer Institute provides a delightful Science Illustrated animation explaining PD-1/PD-L1 immunotherapy and how it fights cancer. Briefly, the treatment helps T-cells recognize cancerous cells that would ordinarily be "disguised" by proteins and attack. The fight is made more fair and effective by immunotherapy and similar cancer treatments.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

Only 2% of human DNA codes for proteins

The entire human genome contains about 20,000 protein-coding genes, with the rest having initially been categorized as "junk" DNA. However, research since 2003 suggests that this "dark genome" regulates how protein-coding genes are expressed in response to environmental factors encountered by cells.

The Hungarian countess rumored to have bathed in blood

According to legend, Hungarian countess Elizabeth Báthory killed up to 600 women to bathe in their blood and preserve her youth. Such allegations have been challenged since the 1980s when Slovakian archivist Josef Kocis published a book detailing new aspects of Báthory's life and included possible evidence of a conspiracy meant to undermine her power as part of Transylvania's ruling dynasty.

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

Oxygen and ozone molecules absorb up to 99.9% of UV radiation reaching Earth

Although they make up no more than 10 out of every million molecules in the ozone layer, ozone provides outsized protection by absorbing the most energetic wavelengths of ultraviolet radiation. This absorption increases thermal energy in the stratosphere, causing temperatures there to rise with altitude.

Supplements are only typically recommended for those with a proven deficiency

Blood tests and other dietary screening tools by clinicians and nutritionists can indicate whether someone is deficient in needed vitamins or minerals, and those results can then lead to a personalized care plan that may include supplements. Supplements can negatively interact with certain medications, so it's important to speak with your doctor about supplements before taking them.

How the most famous Ebola outbreak book got aspects of the disease so wrong

Richard Preston's 1994 book The Hot Zone brought knowledge of Ebola to the masses. But, beyond the poor portrayals of the science and the scientists, the book fostered fearmongering about Ebola, with portrayals of "liquefying," "dissolving," and "bleeding out." These falsehoods about Ebola have persisted for decades and appear to be reinvigorated with every new emergence of the disease.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

The Great Salt Lake's distinct dual coloration results from high-salinity organisms that only live in the northern portion and produce a purple protein.

Poison ivy's rash-causing compound is found in the plant's roots, stem, and leaves—so coming into contact with any part of the plant can lead to rashes for the 85% of people who are allergic to it.

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

Netflix profits when you're not watching, and its movies are designed that way—read a detail-rich critical essay exposing lesser-known Netflix takes

Some coin denominations have ridges etched on their sides, partly to prevent counterfeiting, in a practice called 'reeding.'

The United States is one of only around two dozen countries with a fully federal system of government, in which power is divided between national and state governments.

See how Budweiser's famous Clydesdales spend their days at Warm Springs Ranch, where roughly 70 to 80 of the beer brand's giant horses can be found at any given time.

Power lines are dotted with large, brightly colored balls to improve the visibility of these thin wires to helicopters and small planes and help prevent potential crashes.

To reduce wrinkles in clothing, research recommends gentle wash cycles with more water and tumble drying with smaller loads and longer times.

Dozens of S&P 500 stocks, including Coca-Cola and Walmart—known as the dividend aristocrats—have increased dividends every year for 25 years

Volcanic activity may have triggered the Black Death by spewing gases that led to crop failures in Europe, thus forcing the import of grain ships with plague-infested fleas.

The price of gas is a composite made up of several different factors, with the federal gas tax making up less than 20% of what drivers pay at the pump.

Dorothy's famous entrance into Oz in 'The Wizard of Oz' relied on analog tricks, including a body double and sepia-toned paint, as much as it did on technology

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.