Introduction to immune cell therapy
In 2017, chimeric antigen receiver T cell (CAR-T cell) drug was FDA approved for its high effectiveness in treating blood cancer. Since then, the demand for CAR-T began to increase which led to significant development of related research.
What is immune cell therapy?
Cell therapy is a drug that induces regeneration for restoring damaged or diseased cells by using living cells for new drug development, toxicology testing, bio-marker and much more. Cell therapies are divided into three categories – tissue cell therapy, immune cell therapy and stem cell therapy. This post will specifically focus on immune cell therapy.
Definition of CAR-T cell and its applications
Chimeric antigen receptor T cells (also known as CAR-T cells) are T cells that have been genetically engineered to produce an artificial T cell receptor. The premise of CAR-T immunotherapy is to modify T cells to recognize cancer cells for more effective targeting and destruction. T cells are harvested from people and genetically altered to produce CAR-T cells. Then, the resulting CAR-T cells are infused into patient’s body to attack cancer cells. CAR-T cells can be either derived from T cells in a patient’s own blood (autologous) or derived from T cells of another healthy donor (allogenic). Considering safety issue, CAR-T cells are specifically engineered to an antigen only expressed on cancer cells.
Types of CD marker and their functions
Immunocytotherapy is a treatment that involves immune cells which are considered a key factor of cancer resistance. Once immune cells are cultivated and activated, they are then transplanted back to patient’s body to attack cancer cells. CAR-T is one of the immune cell treatments that is called a “living drug” because it has an ability to kill tumor cells using its own T cell that continues to grow and live after infusion. 
Groups of cell surface antigen or clusters of differentiation are typically abbreviated as ‘CD’ to identify and study cell surface molecules according to their immune expressions. 
For the success of immune cell therapy transplants, positive cells in major differentiation cluster (CD) such as mature T cells (CD3), helper T cells (CD4), killer T-cells or suppressor T cells (CD8) are crucial factors.
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