Erythrocytes

Red blood cells - red blood cells

Unlike other cell types in the human body, mature red blood cells do not contain a nucleus, mitochondria, or ribosomes. The absence of these cellular structures leaves room for hundreds of millions of hemoglobin molecules contained in red blood cells.

Hemoglobin is a component of red blood cells belonging to a group of proteins. It consists of 96% of the protein substance globin and 4% of the substance with a 2-valent iron atom - heme.

In 1 cell of the red blood cell contains about 280 million molecules of hemoglobin, which forms the red color of the blood.

A section of a medical needle under a microscope. Small red dots are red blood cells (erythrocytes).

The animation below takes place in real time (20-second cycle) and shows how the red blood cell, erythrocyte, deforms as it passes through capillaries, and how it changes color during oxygen saturation, passing through the circulatory system.

Alveoli are tiny sacs located at the ends of the tubes in the lungs, and in direct contact with blood. Gas exchange is carried out through the alveoli.

When the air reaches the lungs, oxygen dissolves in the blood through the alveoli, and carbon dioxide gas , on the contrary, enters, lungs for exhalation from the body.

Red blood cells stuck in the resulting thrombus

Malaria is associated with red cell parasite involvement.

Two malaria cells multiply in erythrocytes. One opened to release parasites and infect other cells.

History

2022: Artificial red blood cells have been developed that can bypass kidney and lung protection when delivering drugs

In early March 2022, artificial red blood cells were developed that can bypass the protection of the kidneys and lungs when delivering drugs. The aim is to design the vehicle delivering the drug in such a way that it is directed to a certain point.

From the liver to the kidneys and lungs, the human body is equipped with many levels of filters that protect the body from harmful external materials. But this system also has its own disadvantages. Critical drugs, such as chemotherapy or multiple sclerosis treatment, are also foreign materials, so the body filters out most of these drugs in some cases to 90%. One way to compensate for this problem is to administer significant amounts of medicine to patients. Thus, despite the fact that most of the drug is filtered out, a sufficient amount of it enters the body to perform work. However, higher doses also mean more side effects. To avoid such high doses, another strategy is to design the vehicle delivering the drug in such a way that it is directed to a certain point, so scientists are developing a type of drug delivery vehicle designed to bypass these filters by simulating the properties of an erythrocyte.

Artificial red blood cells have been developed that can bypass kidney and lung protection when delivering drugs

Many drug delivery vehicles do not reach the right place in the body, and the main reason is that our body has a very good filtration system. Therefore, many of them enter the liver, kidneys or spleen. If we can overcome this problem by developing drug delivery vehicles, it will be a significant advance. This is as if you had to attend an event that only people on red cars are allowed to attend, so you borrowed a red car from a friend. You will get where you need to, because you used a car on which you were allowed, said Minkyu Kim, associate professor of materials science and engineering and biomedical engineering.

Kim intends to do just that by receiving the $600,000 CAREER Award, which is awarded by the National Science Foundation in support of emerging teachers who can become role models in research and education. The scientist plans to combine materials science, synthetic biology and multiscale mechanics to develop a modified form of microparticles to deliver drugs designed to bypass the body's filtration systems.

Instead of being a hemoglobin vehicle, the microparticle Kim is developing will be a drug particle vehicle. First, the scientist will use a well-tuned process to place the drug in the nucleus of the microsphere. Then Minkew Kim will add a layer of artificial proteins that the scientist will develop, and then a lipid bilayer. Taken together, these components mimic a red blood cell and even provide a controlled release of a drug that will be able to transport drugs through a series of biological filters to where they are needed.^[1]

Notes