Do red blood cells also have "identity cards"? Scientists have discovered the secret of drug treatment, and can also use it to fight cancer

Red blood cells also have "identity cards"? Scientists have discovered the secret of drug treatment, and can also use it to fight cancer!

1. Why do drugs cause the body to "go on strike"? It turns out that red blood cells have "identity cards"!

As we all know, there are red blood cells in our blood. They are like couriers, busy delivering oxygen to the whole body every day. But do you know? Some drugs can cause red blood cells to "go on strike" and even be eliminated by the immune system as "bad guys"! Professor Li Xiangying's team at Peking University found that a cancer drug called "lenalidomide" can actually make red blood cells grow a special "identity card" - MHC-I molecules. This is like putting a "wanted warrant" on each red blood cell. When the immune system's police CD8+T cells see it, they immediately launch an attack, causing the patient to suffer from **pure red cell aplasia (PRCA), and the body completely loses its red blood cell supply.

2. The process of solving the case is revealed! How did scientists discover the secret of the "ID card"?

Scientists tracked clues like detectives: 1. Found PRCA in multiple myeloma patients taking lenalidomide; 2. Used a microscope to see that the surface of red blood cell progenitor cells was covered with MHC-I (just like finding a "wanted poster"); 3. Verified in the laboratory: T cells will accurately eliminate these cells with "identity cards"; 4. Found a solution: as long as the T cells are transferred away, or antibodies are used to cover the "identity cards", red blood cells can grow normally!

3. Unexpected gain! Equipping red blood cells with a "navigator" turns them into cancer fighters

What's even cooler is that scientists think in reverse: since red blood cells can display their "identity cards", why not equip them with "cancer cell locators"? They use enzyme catalysis technology (like using glue to stick things together) to attach two special markers on the surface of red blood cells:

HPV virus antigens (the "map" that navigates and locates cancer cells) and MHC-I molecules (the "alarm" that activates the immune system).

In animal experiments, the modified red blood cells acted like special forces:

Activate a large number of T cell armies

Combined with PD-1 inhibitors (to remove the "invisibility cloak" of cancer cells)

Eliminating "traitor cells" (MDSCs) in the spleen

Reduce tumor by 80%!

Figure 1. Pathological mechanism of lenalidomide-induced pure red cell aplasia (PRCA).

PRCA erythroid progenitor cells abnormally overexpress MHC-I molecules, and lenalidomide further exacerbates the high expression of MHC-I on the surface of erythroid progenitor cells, thereby enhancing the killing and clearance of these cells by CD8+ T cells. Erythroid aplasia can be effectively alleviated by removing T cells or using antibodies to block MHC-I.

4. What will the hospital of the future look like? Red blood cells become "medical soldiers"

This research brings us two big surprises: 1. Safer treatment: Check the red blood cell "ID card" before taking medicine to avoid drug damage; 2. New anti-cancer weapon: Use the patient's own red blood cells to make "biological missiles" with fewer side effects. Scientists have also verified the safety on monkeys, and in the future it may develop into: customized red blood cell therapy: assemble different anti-cancer markers like Lego; smart red blood cell patrol: search for cancer cells in the blood 24 hours a day.

5. Scientific Tips

Red blood cell courier: 200 million updated every day, lifespan 120 days

Immune police station: T cells, B cells, and NK cells each have their own responsibilities

Inspiration from scientific discoveries: The wisdom of turning bad things into good things (drug side effects inspire anti-cancer therapy)

Protect blood health: Eat more iron-rich foods (spinach, red meat), and have regular physical examinations

This research was not only published in "Nature Communications" and "Cell Discovery", but also tells us: human cells hide countless secrets, and even the most ordinary red blood cells can become superheroes that cure diseases and save lives!

References:

https://www.bio.pku.edu.cn/homes/Index/news_cont/22/17524.html

https://www.nature.com/articles/s41467-024-54571-w

https://www.nature.com/articles/s41421-024-00713-9