About blood and bone marrow donation

Irina Reznik, Mednovosti 

Tatiana Gaponova, Deputy Director General of the Hematology Research Center for Transfusiology, Head of the Department of Blood Cell Processing and Cryopreservation, PhD, told Mednovosti what the ban on paid donation led to, is absolute safety possible during blood transfusion and why the national register of bone marrow donors is so important.

What has changed during this time?

– After the material benefit of donation disappeared, the decline in blood marriage began due to the infections detected in it. Blood quality is very important for our patients, for whom transfusion therapy is an integral part of treatment. And since a lot of these transfusions are required, the risks that donor blood carries are multiplied. If the patient even once faced a blood transfusion, then most likely he will receive complications from this. But when it needs to be done for a long time or for life, then security issues come to the fore here. And we consider it very lucky that this year we managed to completely abandon paid donation. That is, even in cases where, according to the current law, it is possible to pay for complex types of donation – platelet cells or plasma, as well as to attract donors with rare blood groups.

Our donors receive only standard compensation for food and two days of rest to replenish their strength. By the way, we had a funny case with a donor from Australia. (By law, a donor can be a foreigner who has been registered in Russia for more than a year). When he donated blood, donors were given a dry ration – a set of different canned food. And this Australian did not understand what a stew was, he sat for a long time and looked at the jar. But when he came back the next time, he asked to give him the same ration.

Today, the percentage of rejected blood for infectious markers among repeat donors is less than 1%. Among the primary – 2-2.5%. This is if you do not take into account antibodies to the short antigen, which is an additional marker. If we take into account, then it is 5%. We conducted the same study earlier, working with another team of donors, among whom there were many cadets, other groups of a certain risk. And then 13% of people who somehow met with hepatitis B were identified. Therefore, it is so important that donation is not only gratuitous, but also voluntary. With cadets, it is not always possible to be sure of this. A person should come to us voluntarily and have no material motivation. Then it's much more secure.

– How is donor blood tested?

– Since we have been observing our patients for a long time, we see many delayed complications of transfusion therapy. Therefore, we check the donor blood in great detail – more widely than the legislation prescribes to us. In addition to infectious markers, we are also looking for antibodies to viral hepatitis, short antigens. The fact is that the disease often occurs in a latent form, and the person himself does not know that he has had viral hepatitis. Then all the blood is still examined by PCR, that is, the DNA of the virus is searched directly.

This is not even done in all European countries. Because, on the one hand, there is a security strategy, and on the other hand, there is always a cost. If we detect antibodies to hepatitis B in a donor, we must remove him from donation, notify him about it, reject all components. And this selection also costs time and money. We were able to select donors who had not met with hepatitis B, which is very important for our patients, and in this sense we feel quite confident.

But still it is impossible to talk about absolute safety, because there are always risks that the blood can carry infectious agents in such a small amount that it is impossible to fix by laboratory methods. Therefore, the harvested blood is further processed to reduce the number of microbes, if they were there. These techniques are also very expensive, but we need them, as well as everything related to the safety of our patients.

By what criteria can you refuse a person who came to donate blood?

– The law regulates the plan of examination of donors, and there are a number of objective and clearly defined requirements for their health. In addition to HIV, syphilis, transferred viral hepatitis, a number of other diseases, vascular conditions, disability of one degree or another may be a contraindication. That is, everything that can pose a danger to the recipient and the donor himself. "Entrance" control is a doctor's examination, a detailed blood test. Hemoglobin, leukocytes, ESR, and platelet levels in the blood are checked. It is important for us to know the broader parameters that say that, at least, a donor can be a donor, and it will not hurt him.

There are no other formal grounds for refusal. Although in world practice there is a presumption of the donor's guilt, and the doctor may refuse on the basis of his subjective assessment. There is no such rule in our legislation. Therefore, we cannot refuse a person who came with all the documents, wants to be a donor, is sober and was sober by his appearance both yesterday and the day before yesterday. But it is desirable that he be sober most of his life. Therefore, in addition to the mandatory blood indicators, we look at ALT – a liver enzyme that reacts to some errors in the diet, including alcohol consumption.

– What do you do if you detect socially dangerous diseases?

– When hepatitis is detected, we inform the donor himself. If screening tests reveal markers of HIV infection, we are obliged to send the blood of this donor, this particular tube to the Moscow City Center for the Prevention and Control of AIDS. There they double-check it and send us the result if it is negative. If the result is positive, they already contact the donor themselves and invite him for additional examinations. If markers of syphilis are detected, we are obliged to inform the donor and the CVD about it. Syphilis is not transmitted with donated blood, but, of course, it is still rejected.

What cases does this apply to?

– Rhesus affiliation, antigen D, are carried by red blood cells. Therefore, when transfusing plasma and platelets, if the donor is not immunized, the blood group can be ignored. In our practice, we transfuse a lot of platelets and understand how scarce this environment is. It is heavy in the billet, stored for only 5 days, the cost of a single dose of platelets is about 25 thousand rubles. And what to do when a patient needs an urgent transfusion, but there are no platelets of his group? It is necessary to give doctors the right to transfuse platelets of any group and legalize this procedure. The way it is done abroad. I talked about this with our Austrian colleague, the director of a large hematology center. He talked a lot about the logistics of platelets, that after the application, the doctor is guaranteed to receive them within 10 minutes, that all 100% of platelet concentrates undergo viruspathogenic deactivation. I just wanted to applaud. But when asked if platelets are selected by blood type, he answered "no."

– What are the advantages of obtaining blood components separately?

– If we take whole blood from a person, we still subject it to leukofiltration and then divide it into components. About 40-60 ml of suspended platelet alloy is obtained from 450 ml of blood. For platelet transfusion, one patient has to combine 5-6 doses received from different donors, which multiplies different risks: infectious, immunological. Therefore, of course, it is preferable to use hardware techniques in which the therapeutic dose of platelets is obtained by apheresis from a single donor. Inside the automatic separation device, the blood is centrifuged, divided into components, platelets enter a separate container, and red blood cells with plasma are returned to the donor. There are usually 8-9 such cycles. At the same time, the device calculates the time of the procedure, the tolerance of the donor, depending on his physical characteristics and the initial platelet level with which he came to us. But it's still quite a difficult procedure, it takes from 1.5 to 2 hours. And we are very grateful to our regular donors who regularly come to such donations.

– Hematopoietic cells – stem hematopoietic cells of the bone marrow – are taken from the flat bones of the donor's pelvis in the operating room. And we at the donor center then carry out the necessary manipulations with them – separation and cryopreservation of bone marrow suspension. The procedure is performed under epidural anesthesia and lasts 40 minutes. A special needle passes through the periosteum directly into the bone tissue itself, and the liquid part of a small volume is stretched with a syringe – up to 3 cubes. Then the next puncture is made, and the next 3 ml are taken. At the same time, one hole is made on the skin, but the bone itself is "picked" from all sides. You need to collect so many cells so that the patient for whom this is being done is guaranteed to recover. On average, this is 1.5 liters of bone marrow suspension.

The donor, of course, is a little sick later. Bruises appear in the area of taking, the temperature may rise on the first day, as a reaction to the procedure itself, anemia may occur. But all these symptoms in a healthy person pass within 3-5 days and do not require hospitalization or additional anesthesia. There are no global complications associated with exfusion.

Hematopoietic cell transplantation to the recipient is performed intravenously, through a catheter. These are very smart cells: 2 hours after administration, about 30% may disappear into the lungs or liver, but most of them get to the bone marrow niches released by chemotherapy to fit there and give rise to a new hematopoiesis. At the same time, the recipient's blood type changes to the donor's. It takes about a year to "settle" the immunological situation, when the recipient must fully make friends with his new bone marrow and the cells that he produces. Severe immunological problems require therapy, medical supervision, and constant correction of the situation.

– How are bone marrow donors selected?

– In the case of a related donation, it can only be a sibling, from the same parents. It is very difficult to find an unrelated donor compatible with the recipient at the cellular level. It is very important here that the donor cells, once in the patient's body, do not start to conflict with his immune tissue and do not kill him with their young and healthy immune response. Therefore, unfortunately, even in Germany, where the national donor register has been functioning for a very long time, connected with the world, only 80% of those who need a transplant can find a donor in it.

In Russia, the situation is much worse, and the register is just being formed. Besides us, donors are typed in St. Petersburg, Kirov, Saratov, Chelyabinsk. And we actively use their registers for our transplants. Because it costs a lot of money to get a donor in Germany. You have to pay even for the search itself in the database – this information is not provided for free. Plus, we still need to go after him, take the material, bring it here. There are a whole bunch of risks associated with this, up to natural disasters that will not allow you to take off on time. Here, transplantation can be covered by insurance and be free for the patient. And besides, the results of cell transplantation from our national registry are better, because we all look a little more like each other than, say, Germans or someone else.

We are trying to recruit bone marrow donors from blood donors. But we don't even tell them the results of typing, because they don't need it. And the probability that you will fit someone as a donor is very small. This is such a rough, rough analysis, which is simply needed as an information system. And already transplant doctors can put the data of a particular patient in the register and see if there are compatible donors there. And if you're lucky, after an estimated analysis, they request information about the donor, clarify whether his intentions have changed, and conduct additional, parallel studies with the recipient. In our Center, too, we have all been prototyped. And recently we were informed that one of our employees seemed to be compatible with some recipient in St. Petersburg. Here we are now experiencing this with the whole station and waiting for the final conclusions.

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17.07.2015