Learn about gene therapy and cell therapy

What is cell and gene therapy?

Some people think that gene therapy and cell therapy are the same thing, but there are important differences.

With cell therapy, doctors insert new cells of a specific type into your body to repair or replace damaged tissue. Doctors can collect your own cells and then use the treatment to multiply new, healthy cells in the lab before returning them to your body. In other cases, healthy donors provide the new cells. Stem cell transplants (also called bone marrow transplants) are an example of cell therapy.

Gene therapies change the genes inside your cells to treat an inherited or acquired disease. With gene therapy, doctors “fix” a mutated gene (a gene that has changed and no longer works as it should) or replace a mutated gene with a healthy copy by inserting new genetic material into your cells.

How does cell and gene therapy work?

The preparation and administration of cell and gene therapies is a complex and expensive process. And health care providers and other hospital staff must receive extensive training on how to store and handle the cells.

Here is an example of how a treatment – chimeric antigen receptor (CAR) T-cell therapy; — used to treat certain blood cancers. This treatment changes the genes inside your T-cells, a type of immune cell, and trains them to find and kill cancer cells.

Here’s how the process works:

• Your healthcare provider collects T-cells from your blood.
• Scientists in the lab add a gene that helps T-cells stick to a specific part of cancer cells.
• Scientists in the lab grow many copies of the altered cells, which are now called CAR T-cells. This can take several weeks.
• Your doctor will put CAR T-cells into your bloodstream so they can attack cancer cells.

What diseases can cell therapy treat?

Cell therapies have been successful in treating a variety of conditions and diseases, including:

• Autoimmune disorders
• Spinal cord injuries
• Multiple myeloma
• Neurological disorders
• Some forms of leukemia
• Some forms of lymphoma

What diseases can gene therapy treat?

Currently, FDA-approved gene therapies can be used to treat these and other conditions:

• RPE65 mutation-associated retinal dystrophy
• Haemophilia B (congenital factor IX deficiency)
• Spinal muscular atrophy (SMA)
• Beta thalassemia
• Duchenne muscular dystrophy

What are the risks of gene and cell therapy?

Both gene and cell therapies can cause life-threatening side effects, so you will need to be treated at a large medical center where all staff have received special training.

In cell therapy, which restores the immune system, your body will be temporarily unable to fight infections. Your immune system can also increase to dangerous levels. You can get cytokine release syndrome (CRS) when proliferating new cells flood your bloodstream with chemicals called cytokines. CRS can lead to serious breathing and heart problems, along with dangerous fevers, headaches, vomiting and diarrhea.

Other possible side effects of cell therapy include allergic reactions, dangerously low levels of minerals in the blood, and low blood cell counts.

Gene therapy requires the use of a vector, often a virus whose genes have been changed, to deliver the new gene into your cells. Your body may respond to treatment as a threat. If this happens, your immune system can overreact and cause severe inflammation and even organ failure.

It is also possible that the treatment could target the wrong cells, introduce new infection or cause a tumor if the new genes are placed in the wrong place in your DNA.

What are the benefits of gene and cell therapy?

The greatest potential benefit of gene and cell therapy is the opportunity to cure or cure a fatal or serious disease that has limited treatment options. Gene and cell therapies address the underlying cause of the disease at the cellular level. When treatment is successful, these disorders stop getting worse or may even go away completely.

People have approx 20,000 genes, and these genes carry DNA, which tells your cells how to behave. This means that gene therapies create changes at the most basic level of the body. Because of this, gene therapies are usually single-use treatments. Some cell therapies are once-in-a-lifetime treatments, but others may need to be repeated for certain diseases, such as blood cancers.

Gene and cell therapy now and in the future

As of 2017, the FDA has approved it 32 gene and cell therapies, and more endorsements are sure to come in the coming months and years. The American Society for Gene and Cell Therapy (ASGCT) Referencesthat nearly 3,000 gene therapies and cell therapies are in clinical development by 2023. This is in addition to the 850 cell therapies currently in development, ASGCT says.

This is an impressive start to saving and extending lives. Fortunately, research into how gene and cell therapies can treat many other diseases is ongoing, and even more treatments are on the horizon.