Summary
Cells that mature into plasma cells producing antibodies and into memory B cells.
In depth
Each B cell has a unique B cell receptor. With helper T cell help, activation drives proliferation, class switching and affinity maturation in germinal centres. Plasma cells secrete thousands of antibodies per second; memory B cells persist.
B cells present antigen to helper T cells, which give help via CD40L. Isotype switching changes antibody class but not specificity. Memory B cells respond quickly.
Common mistake: B cells mature in bone marrow (B for bursa/bone), T cells in the thymus.
B cells develop in bone marrow, and each rearranges its antibody genes to make a unique receptor. In germinal centres of lymph nodes, B cells undergo somatic hypermutation and selection by follicular helper T cells, leading to higher affinity. They differentiate into plasma cells, which can secrete thousands of antibodies per second, or long-lived memory B cells. Class switching changes IgM to IgG, IgA or IgE while keeping antigen specificity.
T-independent antigens, such as polysaccharides, trigger weak responses without memory, which is why conjugate vaccines are used for infants. B cell cancers include lymphomas and myeloma, and B cell depletion with rituximab treats some autoimmune diseases.
Example: Bruton's agammaglobulinaemia lacks B cells due to a BTK gene defect, so affected boys have recurrent bacterial infections.
Frequently asked questions
What is B Lymphocytes?
Cells that mature into plasma cells producing antibodies and into memory B cells.
Which area of biology covers B Lymphocytes, and how advanced is it?
B Lymphocytes is one of the 52 topics in Immunology & Disease. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Antibodies, Clonal Selection, Primary and Secondary Response.
Can you give an example of B Lymphocytes?
Boosters restimulate memory B cells.
What should I learn before B Lymphocytes?
Work through the Beginner topics in Immunology & Disease first, such as Immune System, Viruses, Innate Immunity, then return to B Lymphocytes. Intermediate topics assume the Beginner vocabulary.
What topics are related to B Lymphocytes?
The closest topics to B Lymphocytes are Antibodies, Clonal Selection, Primary and Secondary Response, Adaptive Immunity. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand B Lymphocytes?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for B Lymphocytes. To practise the whole of Immunology & Disease, use the Immunology & Disease quiz.
How is B Lymphocytes different from Antibodies?
B Lymphocytes: Cells that mature into plasma cells producing antibodies and into memory B cells. Antibodies: Y-shaped proteins made by B cells that bind specific antigens and mark them for destruction. Read both side by side and note what each one explains.
What is a common mistake about B Lymphocytes?
B cells mature in bone marrow (B for bursa/bone), T cells in the thymus.
How should I study B Lymphocytes step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Antibodies and explain the difference aloud. Finally, take the Immunology & Disease quiz and come back to this page for any question you miss.