Antibodies secretion

Antibodies secreted by B cells bind to foreign material (antigen) and serve as tags or identifiers for such material. Antibody-tagged bacteria. 

Perifascicular capillaries are closer to aggregates of antibody-secreting cells (B-lymphocytes) situated in perimysial connective tissue and therefore are most severely affected by antibody-dependent cytotoxic reactions. Immune-complex deposition occurs at a higher level in the vascular tree (i.e., at arteriolar level) and this may cause fluctuations in perfusion pressure. Perifascicular capillaries are most distal from the head of vascular pressure and therefore most likely to suffer from periodic anoxia. 

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

Hieshima K, Kawasaki Y, Hanamoto H, et al. CC chemokine ligands 25 and 28 play essential roles in intestinal extravasation of IgA antibody-secreting cells. J Immunol 2004 173 3668-3675. 

Beckmann, E. and Levitt, D. (1984) Phosphorylcholine on Streptococcus pneumoniae R36a is responsible for in vitro polyclonal antibody secretion by human peripheral blood lymphocytes. Journal of Immunology 132, 2174-2176. 

Stimulates antibody secretion (IgA), proliferation of B cells, and eosinophil differentiation Stimulates growth/differentiation of B cells and secretion of IgG promotes IL-2-induced growth of T cells... 

Catectin promotes tumor cytotoxicity activates macrophages and neutrophils enhances IL-2 receptor expression on T cells inhibits antibody secretion... 

Assays such as this that use polyclonal mitogens for activation may not be as sensitive as specific antigen-driven systems (Luster et al., 1988). In addition, suppression of the mitogen response does not always correlate with the PFC response. Since mitogenesis represents only a small aspect of B-cell function and maturation, this endpoint is not sensitive to early events that may affect activation, or later events that may affect differentiation of B cells into antibody-secreting cells (Klaus and Hawrylowicz, 1984). 

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.

The interaction of antibody-antigen complexes with cells of the immune system results in the activation of a variety of responses ranging from ADCC, mast-cell degranulation, lymphocyte proliferation, antibody secretion and phagocytosis. All these processes are activated via the binding of the Fc domain of the antibody molecule, which is exposed during antibody-... 

Monoclonal antibody, mAb Describes an antibody derived from a single clone of cells or a clonally obtained cell line. Its common use denotes an antibody secreted by a hybridoma cell line. Monoclonal antibodies are used very widely in the study of antigens, and as diagnostics. 

The first two antibodies our group tried to express in this vector system within mammalian cells had mistakes in the genetic material that coded for variable regions and, consequently, did not express any antibody at all. The first antibody that was produced by recombinant technology at IDEC using this vector system was in early 1991. It was supposed to be a chimeric anti-CD4 antibody, but the antibody secreted by the cells did not bind to CD4. CD4 is a surface molecule on the leukocytes known as T cells. A primatized antibody (a chimeric antibody where the variable domains are isolated from a cynomol-gus monkey see Figure 32.2) to CD4 was produced later that year. That antibody ended up in clinical trials in humans at the same time as Rituxan. 

As compared to DCs, B cells are very poor APCs and play a major role as source for antibodies. Upon stimulation by antigens and in the presence of T cells at the border of the T-cell-B-cell area, adjacent to follicles, B cells become antibody-secreting cells and eventually form a germinal center (GC) response. GCs are specialized follicles for B-cell expansion, somatic hypermutation, and class switch recombination, processes that are regulated by T cells, follicular DCs, and other cells. In this process of B-cell maturation, Tregs seem to play a critical role, as in several immune diseases, which are characterized by aberrant antibody... 

In 1975 G. Kohler and C. Milstein [24] demonstrated that it was possible to generate monoclonal antibodies in vitro. The technique involves cloning a single antibody-secreting B lymphocyte so that uniform antibodies can be obtained in large quantities. 

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. 

To obtain MABs, lymphocytes isolated from the spleen of immunized mice (1) are fused with mouse tumor cells (myeloma cells, 2). This is necessary because antibody-secreting lymphocytes in culture have a lifespan of only a few weeks. Fusion of lymphocytes with tumor cells gives rise to cell hybrids, known as hybridomas, which are potentially immortal. 

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