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

Collecting Cells for CAR T-cell Therapy

Your child might benefit from a treatment called CAR T-cell therapy. CAR T-cell therapy is a type of immunotherapy or cellular therapy. CAR T-cell therapy helps the body’s immune system destroy cancer cells.  

The first step is collecting T cells from the blood in a procedure called apheresis. A T cell is a type of white blood cell. 

The blood for T cell collection may come from your child or a donor. T cells can be used right away to make CAR T cells, or they may be frozen to use later. 

How apheresis works 

Apheresis happens in a blood donor center, clinic, or hospital. During the procedure, your child will sit or lie in a chair or bed. A care team member will place an IV in each arm. If your child has a central line, this might be used instead. 

  • The blood flows out and goes through an apheresis machine.  
  • This machine separates white blood cells from the rest of the blood and stores the white cells.  
  • The rest of the blood goes back to the body unharmed. 

The lab counts the white blood cells after the procedure to see if there is enough. Apheresis usually takes 3-6 hours and counting takes 1-2 hours.  Apheresis can be repeated the next day or another time if more cells are needed. 

Side effects of apheresis 

The most common side effects of apheresis include: 

  • Nausea 
  • Fainting 
  • Feeling dizzy  
  • Pain or bruising where the needle was placed 

These side effects are like what you might have from giving blood. 

Apheresis can also lower the number of red blood cells and platelets. Your child might need extra blood through a blood transfusion if this happens.

Side effects from apheresis medicines 

Some people might have side effects from anti-clotting medicines used during apheresis. These medicines keep blood from clotting while it is outside the body. Side effects may include: 

  • Muscle cramps 
  • Numbness or tingling 
  • Feeling cold 
  • Feeling anxious  

One of the anti-clotting medicines, sodium citrate, temporarily lowers the body’s ability to use calcium. Calcium may be given to prevent or treat these side effects. 

Apheresis can temporarily increase your child’s risk of bleeding. The medicine used for apheresis can also lower your child’s levels of platelets. These blood cells help blood clot, so lower platelet levels raise the risk of bleeding. 

The risk of bleeding is even higher if your child takes certain medications before or after the procedure. These medicines include aspirin and NSAIDs, such as ibuprofen and naproxen.  

Avoid aspirin, NSAIDs, and medicines that contain them for 1 week before apheresis and for 2 weeks afterward. Children under 18 should not take aspirin or medicines with aspirin.

If you are not sure if a medicine is safe, please ask your doctor or nurse. 

Key Points

  • CAR T-cell therapy is a treatment that helps the body’s immune system destroy cancer cells. 
  • T cells, a type of white blood cell, are collected from the blood through a process called apheresis. 
  • An apheresis machine takes blood from a vein, separates white blood cells from the rest of the blood, and returns the blood back to the body. 
  • Side effects from apheresis are usually mild and temporary. 

Reviewed: August 2022