B-cells protect you from infection by making proteins called antibodies. B-cells are a type of white blood cell called lymphocytes. When your immune system detects antigens — markers that indicate a threat like a bacteria or virus has entered your body — your B-cells produce antibodies to fight the invader.


What are B-cells (B lymphocytes)?

B-cells are a type of white blood cell that makes infection-fighting proteins called antibodies. B-cells are an important part of your immune system, your body’s defense against harmful pathogens (viruses, bacteria and parasites) that enter your body and make you sick.

B-cells and T-cells are a specific type of white blood cell called lymphocytes. Lymphocytes fight harmful invaders and abnormal cells, like cancer cells. T-cells protect you by destroying pathogens and sending signals that help coordinate your immune system’s response to threats. B-cells make antibodies in response to antigens (antibody generators). Antigens are markers that allow your immune system to identify substances in your body, including harmful ones like viruses and bacteria.

B-cells are also called B lymphocytes.

What are the different types of B-cells?

There are two main types of B-cells: plasma cells and memory cells. Both types help protect you from infection and disease.

  • Plasma cells: Plasma cells release antibodies in response to antigens. Once a B-cell becomes a mature plasma cell, it can release up to 2,000 antibodies per second. Plasma cells are also called plasmacytes or effector cells. They have a shorter lifespan than memory cells.
  • Memory cells: Memory cells remember particular antigens so, if they appear in your body in the future, your immune system can mount a defense quickly. While plasma cells fight bodily invaders by producing antibodies, memory cells help your immune system fight in the future. For example, most vaccines work because they expose your immune system to antigens that your memory cells remember. If an invader appears, your body can mount an attack quickly.


Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy


Why are B-cells important?

B-cells are an important part of your adaptive immune system. Your immune system includes your innate immune system and your adaptive immune system. While your innate immune system is your first defense against any threat, your adaptive immune system is specialized to recognize and fight particular types of threats (a particular virus, bacteria, etc.).

B-cells produce antibodies that destroy antigens or the pathogen associated with a particular antigen. B-cells can also remember specific antigens so your immune system can launch an effective defense if the pathogen ever enters your body again.

How do B-cells work in the immune system?

B-cells work with other cells in your immune system to fight harmful invaders that can make you sick and abnormal cells, like cancer cells. Once B-cells are activated, they become plasma cells that produce antibodies in response to an antigen. Or they become memory cells that remember the antigen so your immune system can quickly identify and fight it in the future.

Generally, the following steps occur when your immune system needs B-cells to fight invaders:

  1. An antigen-presenting cell (APC) attaches to the antigen, breaking it down into smaller pieces. The APC attaches the antigen pieces to a molecule called the major histocompatibility-II complex, or MHC-II.
  2. Helper T-cells (a type of T-cell) bind to the MHC-II complex. This binding activates helper T-cells. Activated helper T-cells are important because they spur B-cells into action.
  3. An activated T-cell attaches to a B-cell, causing it to make copies, or clones, of itself. Some of the B-cells become plasma cells capable of producing antibodies. Other B-cells become memory cells that get stored in your body.
  4. Plasma cells make millions of antibodies over the next several days. All antibodies are customized to destroy only the specific pathogen that produced the antigen.
  5. These antibodies bind to antigens or the part of the pathogen that contains the antigen marker. These antibodies prevent pathogens from causing further harm to your body.



Where are B-cells located?

B-cells exist in different places depending on their stage of development. In fetuses, the liver makes B-cells. Once you’re born, B-cells develop in the spongy tissue inside your bone called bone marrow. They start as hematopoietic stem cells and eventually become B-cells during a process called hematopoiesis. Once they’re fully mature, your B-cells travel to important parts of your lymphatic system, including your spleen and lymph nodes.

Conditions and Disorders

What are the common conditions and disorders associated with B-cells?

Abnormal B-cells can cause autoimmune diseases and various types of cancers.

Autoimmune diseases

Sometimes, B-cells make antibodies in response to antigens associated with your body’s healthy cells. When this happens, the antibodies attack your healthy cells like a dangerous pathogen. This is what happens with autoimmune diseases, including:


Several cancers are associated with abnormal B-cell development, including:


What is the normal range of B-cells?

The normal range of lymphocytes in adults is between 1,000 and 4,800 lymphocytes in every microliter of blood. Approximately 10% to 20% of your lymphocytes are B-cells.

Having consistently high or low B-cells may mean you have a disease or condition. Your healthcare provider will need to perform tests to be sure.

What are the common tests to check the health of my B-cells?

A standard test called a complete blood count (CBC) allows your healthcare provider to identify how many lymphocytes you have. It doesn’t provide specific information about specific types of lymphocytes, B-cells and T-cells.

If they suspect you have a condition related to abnormal B-cells, your provider may order other tests that provide information on specific types of lymphocytes, like a lymphocyte profile (T- and B-cell counts) or a B-cell leukemia/lymphoma panel.


How can I increase my B-cells naturally?

There aren’t widely agreed upon natural remedies for boosting B-cells. Still, there are steps you can take to protect the B-cells you have by keeping your immune system healthy. Many of these recommendations may seem like common sense wellness strategies, but they prevent your body from exhausting essential immune system resources, including your B-cells.

You can keep your immune system healthy by:

  • Getting all recommended vaccines.
  • Eating a well-balanced diet.
  • Managing your stress levels.
  • Avoiding alcohol or drinking in moderation.
  • Not smoking or vaping and quitting if you do.
  • Sleeping at least seven to eight hours each night.
  • Engaging in moderate exercise for at least 150 minutes a week.
  • Washing your hands frequently with soap and water or using hand sanitizer.

Additional Common Questions

What is the difference between T-cells and B-cells?

Both T-cells and B-cells protect you from infection-causing pathogens and diseases, but they play different roles in your immune system. T-cells send signals that control your immune response (helper T-cells) or kill pathogens or infected cells directly (cytotoxic T-cells). B-cells make proteins called antibodies in response to antigens, the markers that let your body know there’s an invader. It’s the antibodies and not the B-cell directly that stops the invader.

A note from Cleveland Clinic

Without B-cells, your body couldn’t make antibodies — the important proteins that help fight harmful pathogens. Along with other lymphocytes and white blood cells, your B-cells keep you infection-free and protect you from abnormal cells. Care for your B-cells and promote overall immune system health by taking steps every day to prevent infections.

Medically Reviewed

Last reviewed on 02/01/2023.

Learn more about our editorial process.

Cancer Answer Line 866.223.8100