Stem cell transplantation for primary immunodeficiency: How it works

Hematopoietic stem cell transplantation can treat several forms of life-threatening immunodeficiency, including severe combined immunodeficiency disorder.

How it works

A stem cell is a type of cell that, under the right conditions, divides to form more stem cells as well as specialized cells with a more specific function. Hematopoietic stem cells produce each of the different types of blood cells, including red blood cells, white blood cells and platelets.

During hematopoietic stem cell transplantation for immunodeficiency disorders, you'll have normal stem cells transferred to your body. The process is similar to a blood transfusion, only the fluid being transfused contains blood and stem cells. The goal is to give you a normally functioning immune system.

Hematopoietic stem cells can be harvested through bone marrow, or they can be obtained from the placenta at birth (cord blood banking). Your stem cell donor — usually a full sibling or a matched donor from a registry — must have body tissues that are a close biological match to yours.

Possible complications

Even with a good match, however, stem cell transplants don't always work. Possible complications include:

  • Graft rejection. If you have enough immune function after the transplant to recognize the transplanted stem cells as foreign, your body might try to reject the stem cells (graft rejection). To weaken your residual immune system and prevent rejection, you might need chemotherapy or radiation before the transplant. Chemotherapy can cause serious side effects, such as severe blistering of the mouth, and leave you temporarily even more vulnerable to infection.
  • Graft-versus-host disease. Mature T cells that develop after the transplant or that come from the donor might sense your tissues as foreign and attack your tissues (graft-versus-host disease). Your doctor might prescribe medications, such as steroids, to suppress inflammation and T cell activation and prevent graft-versus-host disease.

Your health before a hematopoietic stem cell transplant can help predict how you respond to the treatment. You're more likely to have a good outcome if you're in relatively good health, you're free from infection at the time of the treatment and your lungs haven't been damaged by infections.

If you have a severe immunodeficiency disorder and you're interested in hematopoietic stem cell transplantation, ask your doctor about your options. He or she can help you understand the possible risks and benefits.

March 29, 2016 See more In-depth