The fourth case of AIDS healing occurred. Is the spring that has cured AIDS?

Recently at the 24th International AIDS Conference (AIDS 2022), researchers announced a new news that a AIDS patient has achieved long -term relief of AIDS after stem cell transplantation.

Counting this example, to now, human beings have achieved "cure" of 4 patients with AIDS, which is a dawn for AIDS, which was once known as "incurable disease", does it mean that all AIDS diseases mean all AIDS diseases Can it be cured?

Red ribbon picture source: wikipedia

Before answering this question, we must first understand the situation of 4 AIDS patients so far, and their common points can provide us with answers.

1. 4 cases of AIDS "healing"

In November 2008, "New England Medical Magazine" published a sensational research. In this article, a patient from Berlin was reported to have AIDS and leukemia at the same time. After the special stem cell transplantation, both diseases were cured, and within the following two years, the HIV virus was not detected in his body without taking anti -reverse virus drugs (drugs for AIDS).

HIV virus RNA concentration in the patient's body changes over time. Source: reference [1]

As soon as this article comes out, Shi is shocked, because this is the first time in human history that "healing" AIDS, and before that, we believe that AIDS cannot be completely cured, and we can only rely on drugs to suppress and maintain it. Therefore, this patient It is also called "Berlin patient".

After that, in the long years, we never saw a new case again. Until 2020, a new study was published in the medical journal "Liu Ye Dao". Known as "London Patient", the patient also suffers from AIDS and leukemia. After stem cell transplantation, AIDS and leukemia also cured both [2].

Two years later, in February 2022, researchers from the United States reported the third AIDS patient who was "cured": "New York Patient". The patient is the same as the former two, and at the same time suffers from AIDS and leukemia. After umbilical cord blood transplantation, AIDS and leukemia disappear at the same time.

Today, just 5 months later, the fourth patient was cured. This patient was also dual patients with AIDS and leukemia. After stem cell transplantation, these two diseases were cured.

We can see that from 2008 to 2020 to 2022, the frequency of "healing" cases is getting higher and higher. What are the secrets behind this?

Second, 4 cases of "lucky"?

I believe that after reading the above 4 cases of AIDS was cured, the common point of the first time was: Double patients with AIDS+leukemia, they all infected AIDS and suffered from leukemia, but this kind of snow was worse. However, there is no way for mountains and rivers, and Liu Dahua Ming village has given them a new healing opportunity.

Looking at each other further, they all transplanted, and some of them were transplanted with special stem cells.

This seems to be the secret of "healing" AIDS, why is this so?

The secret is hidden in the mechanism of AIDS and leukemia stem cell transplantation.

Third, the secret of the treatment of AIDS and leukemia

AIDS is a infectious disease that has changed color degeneration. It is called the plague of the 20th century. It is caused by human immune defect virus (HIV) infection. This disease is called obtaining it. AIDS, an AIDS, is called AIDS.

From its name, we can basically master the characteristics of their disease, that is, after the infection, it will weaken the immune of the human. This is also one of the important features of AIDS. It is essentially because the HIV virus enters the human body. Attack the human immune system. However, the immune system is the basic guarantee system of our human body. It can identify foreign objects, pathogens, pathogens, and own lesions or aging cell tissues, thereby playing the function of physiological defense, self -stability, and immune surveillance. Once the immune system is weakened due to the attack, then we will face the harm of many diseases, from the slightly martial matter allergies to the pathogen infection, and then to more severe cancer. Most of the causes of AIDS patients are also due to these diseases.

HIV virus (green) comes out of lymphocytes, pictures source: wikipedia

Leukemia is a hemorrhagic disease. It is the human body's white blood cells after various reasons. After various reasons, the proliferation, disorders, and apoptosis are blocked. Finally, the vicious proliferation of the white blood cells is malignant. Organ, so leukemia is often called "blood cancer".

Compared with normal human blood (left), leukemia patients with increased white blood cells (right) Photo source: wikipedia

These two seem to be overwhelming, but there is one thing in common that they are all targeting the immune system. AIDS is aimed at immune cells, and leukemia of leukemia itself is also immune cells. Opportunities for leukemia. For AIDS, we have not cured methods, but for leukemia, we have accumulated a lot of experience. The most typical way to cure leukemia is: hematopoietic stem cell transplantation.

Leukemia is a problem with the blood white blood cells of the human body, and it is not the same as many other organs in the human body. The blood of the human body is an ingredient of continuous regeneration of energy sources. The root cause is that the human body has a special stem cell, that is, hematopoietic stem cells. There are many kinds of stem cells in the human body. They have the potential for proliferation and differentiation, that is, they can constantly copy themselves and differentiate into functional cells. Our human body can eventually form such a complex and diverse tissue structure, and stem cells have achieved great contributions. However, after birth, the vast majority of stem cells gradually lose their dryness, that is, it cannot be differentiated. But hematopoietic stem cells are rare to maintain dryness and sources, so as to constantly generate various ingredients in the blood for us.

Therefore, in the face of the problem of blood, the method of solving the root cause is to directly transplant stem cells to replace the whole set of hematopoietic system, which completely solves leukemia. Because hematopoietic stem cells often exist in the bone marrow of the human body, hematopoietic stem cell transplantation is often called bone marrow transplantation. Umbilical cord blood, as an ingredient of stem cells, naturally has hematopoietic stem cells.

Source of hematopoietic stem cell differentiation. Picture source: wikipedia

This transplantation is not only solved the hematopoietic problem of leukemia, but it also changes the immunity of the human body. Because our immune cells are basically formed from hematopoietic stem cells, one of the most serious problems of AIDS is that immune cells are captured by HIV virus and leading to immune defects. Immune cells have also been updated. Because of this, these "dual unfortunate people" have become "lucky."

Let's take a look at this logic.

1. The human immune cells mainly come from hematopoietic stem cells.

2. HIV attack immune cells, immune cell malignant proliferation in leukemia.

3. After transplanting stem cells, restore the normal hematopoietic function, the immune cells return to normal, the immune cells damaged in AIDS are re -generated by the new hematopoietic system, so they are cured.

Fourth, CCR5Δ32 release prestige

However, it is estimated that when you see this, you must realize that there is a bug here, that is, since the HIV can attack the immune system, even if it is replaced by the hematopoietic system, new immune cells have been produced. Cells form a new infection? After all, changing the bone marrow cannot completely remove the human HIV.

So what are the hidden elements?

The secret is this special source of hematopoietic stem cells.

In fact, as early as the last century, people observed a phenomenon, that is, in the face of AIDS, they were not equal to everyone. Some people had a much lower probability of suffering from AIDS than normal people. Further scientific research finally solved the reason behind this magical phenomenon. These people have a unique genetic mutation, CCR5Δ32 [3].

CCR5 Structure Picture Source: wikipedia

Why does this mutation cause them not to get AIDS? This has to mention the mechanism of AIDS infection.

CCR5 is a receptor protein on the surface of the white blood cells that assumes immune effects in the body. However, when HIV-1 invaded cells, CCR5 helped HIV-1 into the host targeting cells as one of its trend factor receptors, which caused infection, so CCR5 became the accomplice of HIV-1 infection. However, some CCR5 genes in the human body are mutated, which produces Delta 32 mutations, which makes the CCR5 gene cannot be fully expressed. As a result, HIV-1 is lacking and difficult to enter the cells. Naturally, it cannot be infected.

HIV-1 virus enters immune cells through CD4 and CCR5 to enter immune cells.

In fact, the four patients accepted by the stem cells contained in CCR5Δ32, which is the core factors that their newly generated immune systems that can resist HIV after stem cell transplantation.

In comparison, there were Boston patients with HIV and leukemia at the same time, and they were transplanted with ordinary hematopoietic stem cells. As a result, AIDS virus was still not completely cleared after treatment.

5. Is the spring cure for AIDS?

In fact, it's early to talk about this.

We are currently guessing that these "cure" patients' mechanisms are that while we treat their leukemia, because of changing his hematopoietic system, immune cells are also updated, and new immune cells can be exempt from CCR5Δ32 variation, which can be exempted from mutation of CCR5Δ32. The attack infection in HIV also cured AIDS. However, by now, there are only 4 "healing" those who have "healing". There are too few samples, so it is difficult to determine that our current treatment mechanism is completely correct.

Moreover, whether healing needs to be quoted, because the cure time of these cases is too short. In fact, it includes in the research literature, and only after a period of time, it has not been found that HIV or HIV is lower than a certain standard. Whether the HIV virus in their bodies is completely removed still takes the test of time. Even if our mechanism guess is correct, there are still some problems to be resolved.

1. HIV is completely difficult to remove the difficulty

Although the HIV living virus detected in the body of these four patients is basically gone, it cannot be said that the traces of HIV have been completely removed, because HIV also has a special ability, that is, they can integrate to the human body's own genome to reach a long time to reach a long -term group to reach a long -term Reserve [4].

2. The risk of hematopoietic stem cell transplantation is still not low

Although hematopoietic stem cell transplantation has become an important way to treat leukemia, it is not so relaxed in practice. On the one hand, the matching type of hematopoietic stem cells is very complicated, not only complicated than the blood matching type, but also facing serious deficiencies in the supply body. Especially at present, 4 patients still need special CCR5Δ32 mutant hematopoietic stem cells, which is even more rare Essence

Even if you are lucky enough to get the supply body, it is also a very dangerous operation in actual transplantation. Multi -organ complications are prone to occur in hematopoietic stem cell transplantation, such as severe infection in the vacancy of bone marrow during transplantation and the risk of exclusion after transplantation. Therefore Few people are transplanted by bone marrow.

3. Whether CCR5Δ32 variation is completely effective is also a problem

The CCR5 gene is not a dedicated gene that can resist HIV, which has a effect on the immune system and nervous system. Moreover, even for AIDS, CCR5 is not its only body, such as CXCR4 is also HIV receptor. CCR5Δ32 is mainly targeted at the R5-Strain of HIV-1, but AIDS virus has many other types of strains. CCR5Δ32 cannot resist them. And HIV can even bypass CCR5 and CXCR4 for infection, so even if it is a crowd of CCR5Δ32 naturally, it is not completely insulated for HIV.

Because of this, we are still cautious about the current "cure". For most HIV patients, taking the corresponding drugs on time is still the best choice. For the wider unintentional HIV group, we still have to protect, avoid unclean behavior, stay away from drugs, and do not share syringes with others.

Produced: Popular Science China

Author: Li Lei

Producer: China Science Popularization Expo

references:

[1] Hütter G, Nowak D, Mossner M, et al. Long-term Control of HIV by CCR5 DELTA32/Delta32 Stem-Cell Transplantation [J]. New England Journal of Medicine, 2009, 360 (7): 692-6988888888888 Then, then, then

[2]Gupta R K, Peppa D, Hill A L, et al. Evidence for HIV-1 cure after CCR5Δ32/Δ32 allogeneic haemopoietic stem-cell transplantation 30 months post analytical treatment interruption: a case report[J]. The Lancet HIV, 2020 , 7 (5): E340-E347.

[3] Novembre J, Galvani A P, Slatkin M. The Geographic Spread of the CCR5 Δ32 HIV-Resistance Allele [J]. Plos Biology, 2005, 3 (11): E339.

[4] Cohn l B, Silva I T, Oliveira T y, et al. HIV-1 Integrating LandScape During Latent and Active Infection [J]. Cell, 2015, 160 (3): 420-432.

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