Ad
related to: b memory cellsstemcell.com has been visited by 10K+ users in the past month
Search results
Results from the WOW.Com Content Network
Differentiation of memory B cells into plasma cells is far faster than differentiation by naïve B cells, which allows memory B cells to produce a more efficient secondary immune response. [4] The efficiency and accumulation of the memory B cell response is the foundation for vaccines and booster shots.
Some memory B cells can be activated without T cell help, such as certain virus-specific memory B cells, but others need T cell help. [26] Upon antigen binding, the memory B cell takes up the antigen through receptor-mediated endocytosis, degrades it, and presents it to T cells as peptide pieces in complex with MHC-II molecules on the cell ...
Unlike the naive B cells involved in the primary immune response the memory B cell response is slightly different. The memory B cell has already undergone clonal expansion, differentiation and affinity maturation, so it is able to divide multiple times faster and produce antibodies with much higher affinity (especially IgG). [1]
The GC B cells that differentiate into memory B cells are distinct from plasma cell precursors, as they show lower affinity for the antigen [3] [6] and do not need much help from T follicular helper cells. Because of this, many scientists believe that memory B cell precursors are B cells from the light zone that were "non-positively selected."
In humans, CD27 is a good marker for plasma cells; naïve B cells are CD27−, memory B-cells are CD27+ and plasma cells are CD27++. [5] The surface antigen CD138 (syndecan-1) is expressed at high levels. [6] Another important surface antigen is CD319 (SLAMF7). This antigen is expressed at high levels on normal human plasma cells.
These daughter cells either become plasma cells or memory cells. The memory B cells remain inactive here; later, when these memory B cells encounter the same antigen due to reinfection, they divide and form plasma cells. On the other hand, the plasma cells produce a large number of antibodies which are released freely into the circulatory system.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
In humans the splenic marginal zone B cells have evidence of somatic hypermutation in their immunoglobulin genes, indicating that they have been generated through a germinal centre reaction to become memory cells. While naive MZ B cells produce low-affinity IgM antibodies, memory MZ B cells express high-affinity Ig molecules.
Ad
related to: b memory cellsstemcell.com has been visited by 10K+ users in the past month