Introduction
Being diagnosed with a blood cancer or disorder can be a worrying stage for the patient and their loved ones. To manage these fatal conditions, either a healthy bone marrow transplant or blood cells are required to replace them with healthy ones. As blood cancer may affect, the bone marrow or blood cells such as red blood cells (RBCs) and therefore a patient might need a healthy stem cell transplant as it can be only a potential cure for various blood disorders. For a transplant, a matching donor is required, and one way of getting a matching donor for a stem cell transplant is a haplo transplant or haploidentical transplant. In this, the donor is the patient's family member whose tissue type is half-matched with the recipient.
What Are Stem Cells and When Stem Cell Transplants Used?
Stem cells are immature cells present in the body, which later on divide and develop into different types of specialized body cells. These are profoundly present in bone marrow, which is a spongy tissue found in between some bones, such as the hip bone, thigh, and breast bone. There are three types of blood cells which include -
-
Red blood cells, which help in transporting oxygen in the body.
-
White blood cells help in fighting infections.
-
Platelets, which help in blood clotting and stopping bleeding.
A stem cell transplant is mostly used in conditions where the bone marrow or blood cells are commonly affected in conditions like leukemia or aplastic anemia. In the case of blood cancer stem cell transplant may be required if the patient is not responsive to chemotherapy.
What Is a Haplo Transplant?
A haplo transplant or haplo identical transplant is a half-matched stem cell transplant that is taken from the recipient family member. The donor for a haplo transplant can also be the patient's parents, children, siblings, and cousins. Based on genetics, a biological parent or a biological child is always a half-match for the patient. Moreover, the siblings have a 50 percent chance of being a half-match for each other.
Recently, haploidentical transplants have become very popular, as it is much easier this way to find a perfect donor. In patients with any type of blood cancer or blood disorder haploidentical transplant is a relevant option if no other perfect match is available. However, in some cases, haploidentical transplants are not suitable, and they are not easily available in every hospital.
How Does a Haploidentical Transplant Work?
Haplo transplant may or may not be required in every case related to blood disorders. A healthcare professional will need to check the blood to know about the HLA (Human leukocyte antigens) type. The HLA are important parts of the immune system and are present as a protein or marker on various cells of the body. The identification of these markers helps in finding a matching donor. Therefore the doctor will look for a donor who matches the closest HLA type of the recipient. If an HLA-matched donor is not found and the transplant is needed urgently. In that case, the haplo transplant may be done for which one of the family members of the patient can donate the healthy stem cells.
The procedure is the same for both donor and recipient for the transplantation process. However, after a haploidentical transplant, the recipient has to take an extra dose of the chemotherapy drug most commonly used, Cyclophosphamide, after the infusion of donor cells. This chemotherapy agent helps in rebooting the immune system and decreasing the number of active donor T-cells, which may attack the patient’s tissue and may lead to a condition called graft-versus-host disease (GVHD). This condition usually occurs when the donor's immune cells recognize recipient cells as foreign and can attack them. Therefore the patient or recipient has to be carefully monitored in case of a haploidentical transplant to prevent GVHD.
What Will Happen Before the Transplant?
In the case of haplo transplant, when a family member is found to be a suitable match. He or she may have to undergo a donor assessment or medical check-up to make sure they are fit and healthy to donate the cell.
Additionally, in the case of the recipient, they have to undergo conditioning therapy to prepare their bone marrow and immune system for the new cells. This includes chemotherapy and total body irradiation (TBI), which will target any remaining abnormal or cancer-causing cells in the body to prevent any complications.
What Are the Side Effects of Haplo Transplant?
The transplantation procedure is a very extensive procedure that can have an impact on the patient physically as well as mentally. Before the procedure, the patient is informed about all the complications and side effects that they might experience after the transplant.
The side effects may vary from person to person and can be short-term or long-term, depending upon the type of transplant and conditioning therapy.
Short-term side effects may include -
-
High risk of infections.
-
Liver and kidney problems
-
Tiredness.
-
Sore mouth (mucositis).
-
Feeling sick.
-
Loss of appetite.
-
Hair loss.
Long-term side effects may include -
-
Increased risk of infection.
-
Graft versus host disease (GVHD, this condition occurs when the donor's immune cells recognize recipient cells as foreign and can attack them).
GVHD is a serious complication that may occur after a transplant and can affect various parts of the body, most commonly affecting the skin, gut, and liver. This may vary in severity among different individuals and can be a short-term or long-term effect. Therefore the recipient has to be monitored very carefully during the procedure, and the treatment is immediately provided to help control the immune system.
How Is the Recovery Phase After Haplo Transplant?
After the haplo transplant patient might have to stay at the hospital for at least three to four weeks and would be kept under observation. During this time, the patient will be in protective isolation to let the immune system start rebuilding. However, after the hospital time, it may still take 6 to 12 months to get normal and return to the usual lifestyle.
Conclusion
The haplo transplant has been a great discovery that helps in increasing the chance of finding a suitable donor, as everyone has at least one haploidentical relative. Therefore it is a much quicker and safer way to get a healthy transplant. With advancements in the medical sector, the complications of haplo treatment have greatly reduced, such as GVHD. However, this procedure is not available everywhere as it is a relatively new approach.
