Skip to Main Content

Welcome to

Together is a new resource for anyone affected by pediatric cancer - patients and their parents, family members, and friends.

Learn More

Peripheral Blood Stem Cell (PBSC) Donation  

Peripheral blood stem cell (PBSC) donation is the collection of blood-forming cells (stem cells) from blood in the veins. Stem cell donors are sometimes needed for patients who need a stem cell transplant. Cells can come from bone marrow or from peripheral blood.

Steps of PBSC include:

  • Lab tests of donor blood
  • Medicine to increase the number of circulating stem cells (mobilization)
  • Collecting stem cells from blood through a vein (apheresis)

Blood tests

Before stem cell donation, donor blood is tested for infectious diseases such as viruses. This step is important because transplant patients are not able to fight infection because of a weakened immune system.

Mobilization of stem cells

Before stem cells are collected, the donor will receive a medicine called granulocyte-colony stimulating factor (G-CSF). G-CSF is a blood growth factor that increases the number of stem cells that circulate in the blood. The movement of stem cells from the bone marrow to the blood is called mobilization.

G-CSF is given as an injection (shot) once a day. The number of days will be prescribed by your care team. Female donors of childbearing age must have a pregnancy test before taking G-CSF.

Illustration of stem cell mobilization showing bone marrow, stem cell, and blood vessel.

Stem cell mobilization is the process of using certain medicines to make stem cells move from the bone marrow to the blood.

G-CSF side effects 

Side effects of G-CSF are usually mild and go away after stem cell donation. The most common side effects are flu-like symptoms such as low-grade fever, chills, bone pain, headache, and trouble sleeping. The doctor may order acetaminophen (Tylenol®) or other medicines to relieve these symptoms.

Stem cell collection (apheresis)

apheresis image showing saline bag, stem cells bag, apheresis machine

Stem cell collection occurs through a procedure called apheresis.

Stem cells are collected from the blood through a process called apheresis.

  1. A catheter is placed into a vein in the donor’s arm.
  2. An apheresis machine takes blood from the vein and separates the stem cells from the other types of blood cells.
  3. The machine returns the remaining blood back to the donor through a vein in the other arm.

This machine is the same type used to collect platelets. A medicine called citrate is given during apheresis to prevent blood from clotting while it is outside of the body.

In most cases, this process uses temporary IVs placed in the arms. Occasionally, a surgically placed line is needed.

The apheresis process takes about 3 to 8 hours per session. During this time, the donor sits in a reclining chair or bed. Apheresis is repeated over 1-3 days until enough stem cells are collected for transplant.

Apheresis side effects

Side effects of apheresis are similar to whole blood donation. The most common side effects are nausea, fainting, dizziness, and bruising at the needle site.

Some people may have side effects due to the citrate. These include muscle cramps, numbness, feeling cold, tingling sensations, or anxiety. Sometimes, calcium is given by mouth or through the vein to prevent or treat these symptoms.

Apheresis may cause a temporary decrease in platelet count or white blood cell count . This decrease is usually minor and does not cause any problems.

Donors should not take aspirin or NSAIDs while the platelet count is low. These medicines may increase the risk of bleeding. Do not take aspirin or NSAIDs while receiving G-CSF and for 2 weeks after peripheral blood stem cell donation unless instructed by a health care provider.

Reviewed: August 2022