Antibodies plasma cells

After recognizing antigens through membrane-bound antibodies, there is B cell proliferation and differentiation for about 4-5 days. This results in the production of plasma and memory cells. One of the five classes of antibodies are produced and secreted by plasma cells that do not possess membrane-bound antibodies. Plasma cells survive for about 1-2 weeks. 

Plasma cell. A terminally differentiated B lymphocyte with little or no capacity for mitotic division that can synthesize and secrete antibody. Plasma cells have eccentric nuclei, abundant cytoplasm, and distinct perinuclear haloes. The cytoplasm contains dense rough endoplasmic reticulum and a large Golgi complex. 

A B lymphocyte is a specific type of white blood cell (leucocyte) derived from bone marrow stem cells. Each B lymphocyte expresses an immunoglobulin (antibody) specific for a particular antigen. Following antigenic stimulation, a B lymphocyte may differentiate and multiply into plasma cells that secrete large quantities of monoclonal antibody. 

These are supplied by the secretion of peptide molecules (termed cytokines or lymphokines) fiom a subset of the T-cell family (the helper T cells, TH cells). These peptide molecules (interleukins (IL) 2,4,5 and 6) stimulate the B cells to proliferate, undergo clonal expansion and mature into plasma cells which secrete antibody and also into the longer-hving, non-dividing memory cells. 

Subsequent antigenic stimulation results in high antibody titres (secondary or memory resporrse) as there is now an expanded clone of cells with memory of the original antigen available to proliferate into mature plasma cells (Fig. 14.1). 

Plasma cell A lymphocyte that is a mature antibody-secreting B cell. 

Somatic hypermutation High frequency of mutation that occurs in the gene segments encoding the variable regions of antibodies during the differentiation of B lymphocytes into antibody-producing plasma cells. 

Wilson E, Butcher EC. CCL28 controls immunoglobulin (Ig)A plasma cell accumulation in the lactating mammary gland and IgA antibody transfer to the neonate. J Exp Med 2004 200 805-809. 

Taylor CR, Burns J. The demonstration of plasma cells and other immunoglobulin containing cells in formalin-fixed, paraffin-embedded tissues using peroxidase labelled antibody. J. Clin. Pathol. 1974 27 14-20. 

Plants have the ability to assemble immunoglobulin heavy chains and light chains to form full-length antibodies very efficiently [24]. In mammalian plasma cells, the assembly mechanism is only partially understood. The immunoglobulin light and heavy chains are synthesized as precursor proteins, and signal sequences direct... 

Activated B cells produce plasma cells, which form antibodies that, in combination with complement, result in accumulation of polymorphonuclear leukocytes. Polymorphonuclear leukocytes release cytotoxins, oxygen free radicals, and hydroxyl radicals that promote cellular damage to synovium and bone. 

Plasma cells Secrete antibody terminally differentiated... 

Figure 1.7. Lymphocyte activation. When naive lymphocytes first encounter the antigen that is recognised by their receptor, they are stimulated to differentiate and proliferate. This clonal expansion is aided by the production of cytokines. Two cell types develop from this process the effector cells (i.e. either antibody-secreting plasma cells or cytotoxic T cells) and memory cells. Both cell types possess virtually the same receptor that was expressed on the naive lymphocyte.

When B lymphocytes are stimulated by antigen they develop into plasma cells. The receptor of plasma cells can be secreted from the cell because some of these molecules lack the hydrophobic domain that normally anchors the receptor to the plasma membrane. These secreted molecules are immunoglobulins or antibodies and have a common structure (Fig. 1.8). They are found in a variety of bodily fluids and in many tissues. 

Plasma cells are B lymphocytes that are in the process of synthesizing antibody protein. 

A myeloma is a cancer of the antibody-producing plasma cell and as such is immortal. 

Hybridoma Cell produced by the fusion of antibody-producing plasma cells with myeloma/carcinoma cells. The resultant hybrids have then the capacity to produce antibody (as determined by the properties of the plasma cells), and can be grown in continuous culture indefinitely owing to the immortality of the myeloma fusion partner. This technique enabled the first continuous supply of monoclonal antibodies to be produced. 

So-called, B lymphocytes, which constitute about 20% of the total lymphocyte population in the blood, have only one major function which is to synthesize and secrete immunoglobulin antibodies. Following an antigenic challenge, B cells develop into plasma cells whose role is to produce specific immunoglobulin molecules in what is known as the humoral arm of the immune response. 

Antibody a protein produced by plasma cells as part of the humoral immune response that has the ability to recognize and bind to the antigen that elicited it. 

Antigen a molecule capable of eliciting the formation of antibodies by plasma cells. 

B cell a type of white blood cell that develops in the blood marrow and can be induced to differentiate into an antibody-secreting plasma cell. 

Plasma cell an antibody-secreting cell of the blood. 

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