4.1.5.Cytokine and Chemokine in inflammation:
Many multifunctional cytokines are present in exocytosis of mast cells which play important roles in late- phase inflammatory response. The mast cell is a source of cytokines such as IL-1, -2, -4, -5, -6, TNF-α (85). IL-1 functions to grow T-helper cells and B cells with its proliferation whereas IL-2 influences the proliferation of T lymphocytes and activation of B lymphocytes. IL-4 helps to differentiate B lymphocytes into plasma cells secret IgE. With TNF-α, IL-4 regulates the expression of both high- and low-affinity IgE receptor on antigen presenting cells. IL-5 activates B lymphocytes and helps in the differentiation of eosinophils, and IL-6 causes B lymphocytes to increase the synthesis and …show more content…
TNF, produced by activated macrophages and T lymphocytes, exerts its effects by binding with specific TNF receptors on cell surfaces. TNF receptors are called transmembrane receptors which extend to the outside cell through the cell membrane from inside the cell. The lock and key binding takes place between TNF and protruding part of the receptors. These cell surface TNF receptors may be released as free-floating molecules, known as soluble TNF receptors (sTNFR). TNF can bind with receptors whether these are still attached to cells or are in soluble form. TNF known to activate the inflammatory response when bound to cell surface receptor. In contrast, when TNF binds to floating receptors, it is found to inhibit the inflammatory cascade. Normally, the body strictly maintains the balance between the amounts of TNF produced the quantity of cell-surface bound and soluble TNF receptors …show more content…
macrophage or target endothelial cell), releasing ligand or receptors, respectively. In inflammatory and infectious conditions, serum and tissue TNF levels are elevated where as normally it is not detectable in healthy individuals (93-94).Serum TNF levels correlate with the severity of infections (95-96). Usually monocytes or macrophages are the main sources of TNF in inflammatory disease. But other cells also can produce TNF like mast cells, T and B lymphocytes, natural killer (NK) cells, neutrophils, endothelial cells, smooth and cardiac muscle cells, fibroblasts and
Many multifunctional cytokines are present in exocytosis of mast cells which play important roles in late- phase inflammatory response. The mast cell is a source of cytokines such as IL-1, -2, -4, -5, -6, TNF-α (85). IL-1 functions to grow T-helper cells and B cells with its proliferation whereas IL-2 influences the proliferation of T lymphocytes and activation of B lymphocytes. IL-4 helps to differentiate B lymphocytes into plasma cells secret IgE. With TNF-α, IL-4 regulates the expression of both high- and low-affinity IgE receptor on antigen presenting cells. IL-5 activates B lymphocytes and helps in the differentiation of eosinophils, and IL-6 causes B lymphocytes to increase the synthesis and …show more content…
TNF, produced by activated macrophages and T lymphocytes, exerts its effects by binding with specific TNF receptors on cell surfaces. TNF receptors are called transmembrane receptors which extend to the outside cell through the cell membrane from inside the cell. The lock and key binding takes place between TNF and protruding part of the receptors. These cell surface TNF receptors may be released as free-floating molecules, known as soluble TNF receptors (sTNFR). TNF can bind with receptors whether these are still attached to cells or are in soluble form. TNF known to activate the inflammatory response when bound to cell surface receptor. In contrast, when TNF binds to floating receptors, it is found to inhibit the inflammatory cascade. Normally, the body strictly maintains the balance between the amounts of TNF produced the quantity of cell-surface bound and soluble TNF receptors …show more content…
macrophage or target endothelial cell), releasing ligand or receptors, respectively. In inflammatory and infectious conditions, serum and tissue TNF levels are elevated where as normally it is not detectable in healthy individuals (93-94).Serum TNF levels correlate with the severity of infections (95-96). Usually monocytes or macrophages are the main sources of TNF in inflammatory disease. But other cells also can produce TNF like mast cells, T and B lymphocytes, natural killer (NK) cells, neutrophils, endothelial cells, smooth and cardiac muscle cells, fibroblasts and