Table of Contents
How B cells are activated and differentiate into plasma cells?
When a naïve or memory B cell is activated by an antigen, it proliferates and differentiates into an antibody-secreting effector cell, known as a plasmablast or plasma cell. Additionally, B cells present antigens (they are also classified as professional antigen-presenting cells (APCs)) and secrete cytokines.
What happens during the secondary immune response?
During the secondary immune response, the immune system can eliminate the antigen, which has been encountered by the individual during the primary invasion, more rapidly and efficiently. Both T and B memory cells contribute to the secondary response.
How do B cells differentiate?
activated B cells differentiate into plasma cells in primary foci that are outside of the follicles, then migrate to the medullary cords of the lymph node or to the bone marrow. Secrete IgM within 4 days. Other activated B cells enter the follicle, divide and differentiate; germinal centers form.
Where do B cells differentiate into plasma cells?
Germinal center
Upon stimulation by a T cell, which usually occurs in germinal centers of secondary lymphoid organs such as the spleen and lymph nodes, the activated B cell begins to differentiate into more specialized cells. Germinal center B cells may differentiate into memory B cells or plasma cells.
What is the difference between B cell and plasma cell?
Summary – B Cells vs Plasma Cells The key difference between B cells and plasma cells is that B cells are a type of white blood cells which produce antibodies against different pathogens in adaptive immunity while plasma cells are a type of activated B cells.
How are plasma cells activated?
B cells differentiate into plasma cells that produce antibody molecules closely modeled after the receptors of the precursor B cell. Once released into the blood and lymph, these antibody molecules bind to the target antigen (foreign substance) and initiate its neutralization or destruction.
How does the immune system activate T and B cells?
T and B cells are activated when they recognize small components of antigens, called epitopes, presented by APCs, illustrated in Figure 2. Figure 2. An antigen is a macromolecule that reacts with components of the immune system. A given antigen may contain several motifs that are recognized by immune cells.
What distinguishes the secondary immune response from the primary immune response?
Primary Immune Response is the reaction of the immune system when it contacts an antigen for the first time. Secondary Immune Response is the reaction of the immune system when it contacts an antigen for the second and subsequent times.
What do activated B cells differentiate into?
Upon activation, B cells proliferate and form germinal centers where they differentiate into memory B cells or plasma cells. Following differentiation into plasma cells, additional signals initiate plasma cell antibody class switching and regulate antibody secretion.
When does B cell differentiation occur?
It takes about 1 or 2 weeks for original B cells to become mature B cells, during which they randomly rearrange their Ig genes to generate Ag-specific B-cell receptors (BCRs) capable of recognizing a wide variety of Ags. Each B cell produces a single species of antibody, each with a unique antigen-binding site.