Your immune system

The immune system is your body's natural defense against disease and infection. When your immune system is working properly, it is able to recognize and attack millions of "foreign" invaders, called antigens, that cause infection. It also has the ability to protect your body from unhealthy cells such as cancer.

Parts of the immune system

The immune system is made up of a complex network of organs, tissues, and cells.

  • Bone marrow is the soft tissue in the center of your bones where blood cells are made
  • The lymphatic system is a group of tissues, vessels, and organs throughout your body, including the spleen, thymus, and lymph nodes, that make and store white blood cells
  • White blood cells, including lymphocytes (such as B cells and T cells) and phagocytes (or cells that swallow and digest foreign particles), move through blood and tissues looking for foreign invaders

Cells of the immune system

b cells

B cells

B cells play an important role in protecting your body from infection and disease by making specific proteins, called antibodies, that flood the bloodstream looking for foreign invaders. When the antibodies encounter the foreign invaders they attach to them and alert the immune system to attack with T cells and other immune cells.

t cells

T cells

T cells play an important role in protecting your body from infection and disease by finding and killing cells that are infected or cancerous.



Phagocytes play an important role in protecting your body from infection and disease by engulfing and destroying foreign particles such as bacteria and viruses. Phagocytes also help to rid the body of dead cells and other cell debris.

Cancerous cells

cancerous cells
Healthy B cells and T cells can change, forming abnormal cells. Abnormal B cells and T cells that grow and multiply uncontrollably may develop into cancer. Abnormal B cells in the lymph nodes that continue to grow and multiply can result in mantle cell lymphoma (MCL).
cancerous cells

What is mantle cell lymphoma?

MCL is a type of non-Hodgkin lymphoma (NHL). MCL happens when B cells in the mantle zone (or outer ring) of the lymph node follicles have become cancerous and may spread to other parts of the body.

mantle cell lymphoma in the body

In addition to enlarged or abnormal lymph nodes, symptoms of MCL can include:

  • Unexplained weight loss
  • Drenching night sweats
  • Fever
  • Fatigue
  • Increased number of white blood cells
  • Pain
  • Swelling of liver and spleen
  • Gastrointestinal symptoms (indigestion, abdominal pain, bloating)
  • Skin rash
  • Nausea
  • Diarrhea
  • Vomiting

What is relapsed or refractory (R/R) MCL?

Relapsed patients are patients who experience their disease returning after a period of improvement.

Refractory patients are patients who have disease that does not respond to treatment.

TECARTUS™ is a treatment approved for R/R mantle cell lymphoma. This means it is used when your other treatments either didn’t work or have stopped working for MCL.