Search results
Results from the WOW.Com Content Network
Of the three B cell subsets, FO B cells preferentially undergo T cell-dependent activation while MZ B cells and B1 B cells preferentially undergo T cell-independent activation. [ 16 ] B cell activation is enhanced through the activity of CD21 , a surface receptor in complex with surface proteins CD19 and CD81 (all three are collectively known ...
The inactive B and T cells are so featureless with few cytoplasmic organelles and mostly inactive chromatin that until the 1960s textbooks could describe these cells, now the central focus of immunology, as having no known function! [11] However, T and B lymphocytes are very distinct cell lineages and they ‘grow up’ in different places in ...
A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. [1] Lymphocytes include T cells (for cell-mediated and cytotoxic adaptive immunity), B cells (for humoral, antibody-driven adaptive immunity), [2] [3] and innate lymphoid cells (ILCs; "innate T cell-like" cells involved in mucosal immunity and homeostasis), of which natural killer cells are an ...
The T cell-dependent processes are subdivided into primary and secondary responses: a primary response (meaning that the T cell is present at the time of initial contact by the B cell with the antigen) produces short-lived cells that remain in the extramedullary regions of lymph nodes; a secondary response produces longer-lived cells that ...
When the first immortalized T cell lines began to emerge, it became possible to observe which T cells had specific effects on B cells. Various T cell types secreted factors that induced Ig production, in some cases only of specific kinds or only in the presence of antigen. Some IgG classes secreted by B cells are exclusively T cell dependent. [7]
They present the antigen to T cells and, if there is a T cell with the appropriate T cell receptor, it will be activated. [25] B cells acquire antigen directly from the afferent lymph. If a B cell binds its cognate antigen it will be activated. Some B cells will immediately develop into antibody secreting plasma cells, and secrete IgM.
Once mature, T cells emigrate from the thymus to provide vital functions in the immune system. [11] [12] Each T cell has a distinct T cell receptor, suited to a specific substance, called an antigen. [12] Most T cell receptors bind to the major histocompatibility complex on cells of the body.
Additionally, the T cells are able to help the B cells by the interaction of the T cell CD40 ligand with the B cell CD40 molecule, which causes a signaling cascade that is beneficial for the survival and proliferation of B cells. B cell receptor activation results in the activation of the NF-kB signaling pathway, which is essential for the ...