Monocyte-directed migration

Humrich JY, Humrich JH, Averbeck M, et al. Mature monocyte-derived dendritic cells respond more strongly to CCL19 than to CXCL12 consequences for directional migration. Immunology 2006 117(2) 238-247. 

Herold S, von Wulffen W, Steinmueller M, Pleschka S, Kuziel WA, Mack M, Srivastava M, Seeger W, Maus UA, Lohmeyer J (2006) Alveolar epithelial cells direct monocyte transepithelial migration upon influenza virus infection impact of chemokines and adhesion molecules. J Immunol 177(3) 1817-1824... 

Imai Y, Ibata I, Ito D, Ohsawa K, Kohsaka S (1996) A novel gene ibal in the major histocompatibility complex class III region encoding an EF hand protein expressed in a monocytic lineage. Biochem Biophys Res Commun 224 855-862 Imitola J, Raddassi K, Park KI, Mueller FJ, Nieto M, Teng YD, Frenkel D, Li J, Sidman RL, Walsh CA, Snyder EY, Khoury SJ (2004) Directed migration of neural stem cells to sites of CN S injury by the stromal cell-derived factor lalpha/CXC chemokine receptor 4 pathway. Proc Natl Acad Sci USA 101 18117-18122... 

Over the past ten years, more than 40 unique human and murine cytokines have been identified as members of chemokine superfamily of chemoattractants. These cytokines have been shown to induce the directional migration of selected cell types including neutrophils, monocytes, macrophages, dendritic cells, lymphocytes, basophils, eosinophils, and fibroblasts. 

Chemokines in Leukocyte Trafficking CKs are thought to be centrally involved in leukocyte trafficking and not limited to attraction of monocytes by the CC family and neutrophils by the CXC family. Other functions of the CKs include expression of adhesion molecules, especially for the lymphocytes in both the migratory response and maturation and proliferation. The selective chemoattractant qualities shown by CKs explain the directed migration of each kind of leukocyte or even of subtypes of these cells (as T and B lymphocytes, perhaps even Thl and Th2). Several studies have shown that CC CKs attract T lymphocytes and that CD45R0, memory-phenotype cells are considered to be the main responders. The results, however, have often been contradictory, and the role of lymphocyte activation and proliferation is still unclear. The CC CKs MCP-2, MCP-3, RANTES, MIP-la, MIP-lp, and MCP-1 induce significant, dose-dependent transendothelial chemotaxis of... 

Xu, L. L., Warren, M. K., Rose, W. L., Gong, W., and Wang, J. M. (1996). Human recombinant monocyte chemotactic protein and other C-C chemokines bind and induce directional migration of dendritic cells in vitro. J. Leukoc. Biol. 60, 365-371. Yla-Herttuala, S., Lipton, B. A., Rosenfeld, M. E., Sarkioja, T., Yoshimura, T., Leonard, E. J., Witztum, J. L., and Steinberg, D. (1991). Expression of monocyte chemoattractant protein-1 in macrophage-rich areas of human and rabbit atherosclerotic lesions. Proc. Natl. Acad. Sci. USA 88, 5252-5256. 

In the inflammatory response the cellular component can be said to begin with directed migration of phagocytic cells, both polymorphonuclear leukocytes (PMN s) and mononuclear monocytes (MC s) and macrophages (HP s). This process is termed chemotaxis and depends upon signals received at the cell surface which are translated into cellular motility dependent upon actin/myosin polymerization near the cell membrane (Stossel, 1975). In PEM patients in both Peru (Freyre et al., 1973) and Thailand (Kulapongs et al.,... 

It is accepted that oxidation of LDL is a key event in endothelial injury and dysfunction. Oxidised LDL (oxLDL) may directly injure the endothelium and trigger the expression of migration and adhesion molecules. Monocytes and lymphocytes interact with oxLDL and the phagocytosis which follows leads to the formation of foam cells, which in turn are associated with the alteration of the expression pattern of growth regulatory molecules, cytokines and pro-inflammatory signals. The proposed role of oxLDL in atherogenesis, based on studies in vitro, is shown in Fig. 2.1. 

PDE IV inhibitors, as well as some combined PDE IIl/IV inhibitors, are currently under development for the treatment of asthma (Christensen and Torphy, 1994 Nicholson and Shahid, 1994). The basis for this development includes bronchodilatory activity directly related to inhibition of PDE IV, and/or PDE III, in airway smooth muscle, as well as the antiinflammatory activity of these compounds. PDE IV is the major cAMP PDE isozyme present in inflammatory cell types and inhibition of PDE IV has been linked to elevation of cAMP and inhibition of histamine or leukotriene release from mast cells, inhibition of oxygen free radical release from eosinophils or neutrophils, inhibition of adhesion, migration, or activation of eosinophils, and inhibition of TNF-a release from human monocytes (see Nicholson and Shahid, 1994, or Christensen and Torphy, 1994, for some reviews). There are now known to be at least four sub-types of PDE IV that are encoded by different cDNAs (Bolger et al., 1993 Davis et al, 1989 Livi et al., 1990). Although sequence homology of 75-90% is evident among subtypes, key differences, as well as cellular distribution, are apparent. Currently there are no selective inhibitors of the PDE IV subtypes. 

Chemokines induce directed chemotaxis in nearby responsive cells. They are released from various cells in response to bacteria and viruses infection and in response to agents that cause physical damage such as silica or urate crystals. The main functions of chemokines are chemoattractants for leukocytes. They help to recruit monocytes, neutrophils, and other effector cells from the blood to the sites of infection or damage. They serve to guide cells involved in innate immunity and in the adaptive immune system. Some chemokines have other roles in the development of lymphocytes, migration, and the growth of new blood vessels. 

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