Mononuclear phagocyte

Neutrophils and host defence The fight against infection 

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The very early peak of neutrophil invasion into an inflamed area is followed several hours later by a wave of a second class of phagocytic cells, the macrophages. This biphasic pattern of inflammatory cell movement and accumulation is observed in most acute inflammatory responses. The mononuclear phagocyte in the blood is known as the monocyte and differentiates... 

A class of immunoregulatory polypeptides produced by various cells types, but predominantly by mononuclear phagocytes activated by signals provided by exogenous pyrogens. These peptides act as endogenous pyrogens. 

This section will briefly discuss the clearance kinetics and tissue distribution of liposomes in vivo (reviewed by Senior, 1987 Hwang, 1987 Gregoriadis, 1988a Hwang end Beaumier, 1988 Juliano, 1988). Liposomes, when administered in vivo by a variety of routes, rapidly accumulate in the mononuclear phagocyte system (MPS), also referred... 

In addition to the reports of uptake of intact small liposomes (SUV) by hepatocytes (Scherphof et al., 1983), there is some evidence of uptake of intravenously administered liposomes as intact structures by cells other than mononuclear phagocytes of the MPS. Recently, the integrity of the capillary endothelial barrier in several pathophysiological conditions was discussed (Bodor and Brewster, 1986). Several studies already indicated an increased capillary permeability during inflammation both in animals (Lopez-Berestein et al., 1984a) and in man (Morgan et al., 1985 Williams et al., 1987). 

Allen, T. M. (1988). Toxicity of drug carriers to the mononuclear phagocyte system, Adv. Drug Dehv. Rev.. 2, 55-67. 

Becker, S. (1988). Functions of the human mononuclear phagocyte system A condensed review, Adv. Drug Deliv. Rev., 3, 1-100. 

These proteins are called acute phase proteins (or reactants) and include C-reactive protein (CRP, so-named because it reacts with the C polysaccharide of pneumococci), ai-antitrypsin, haptoglobin, aj-acid glycoprotein, and fibrinogen. The elevations of the levels of these proteins vary from as little as 50% to as much as 1000-fold in the case of CRP. Their levels are also usually elevated during chronic inflammatory states and in patients with cancer. These proteins are believed to play a role in the body s response to inflammation. For example, C-reactive protein can stimulate the classic complement pathway, and ai-antitrypsin can neutralize certain proteases released during the acute inflammatory state. CRP is used as a marker of tissue injury, infection, and inflammation, and there is considerable interest in its use as a predictor of certain types of cardiovascular conditions secondary to atherosclerosis. Interleukin-1 (IL-1), a polypeptide released from mononuclear phagocytic cells, is the principal—but not the sole—stimulator of the synthesis of the majority of acute phase reactants by hepatocytes. Additional molecules such as IL-6 are involved, and they as well as IL-1 appear to work at the level of gene transcription. 

Giuhan D, Vaca K, Noonan CA (1990) Secretion of neurotoxins by mononuclear phagocytes infected with HIV-1. Science 250(4987) 1593-1596 Giuhan D, Wendt E, Vaca K, Noonan CA (1993) The envelope glycoprotein of human immunodeficiency virus type 1 stimulates release of neurotoxins from monocytes. Proc Natl Acad Sci USA 90(7) 2769-2773... 

Giuhan D, Yu J, Li X, Tom D, Li J, Wendt E, Lin SN, Schwarcz R, Noonan C (1996) Study of receptor-mediated neurotoxins released by HIV-1-infected mononuclear phagocytes found in human brain. J Neurosci 16(10) 3139-3153... 

McElrath MJ, Pruett JE, Cohn ZA (1989) Mononuclear phagocytes of blood and bone marrow comparative roles as viral reservoirs in human immunodeficiency virus type 1 infections. Proc Natl Acad Sci USA 86(2) 675-679... 

Persidsky Y, Zheng J, Miller D, Gendelman HE (2000) Mononuclear phagocytes mediate blood-brain barrier compromise and neuronal injury during HIV-l-associated dementia. J Leukoc Biol 68 413 22... 

Gelman BB, Wolf DA, Rodriguez-Wolf M et al (1997) Mononuclear phagocyte hydrolytic enzyme activity associated with cerebral HIV-1 infection. Am J Pathol 151 1437-1446 Giraudon P, Buart S, Bernard A et al (1997) Cytokines secreted by gUal cells infected with HTLV-I modulate the expression of matrix metalloproteinases (MMPs) and their natural inhibitor (TIMPs) possible involvement in neurodegenerative processes. Mol Psychiatry 2(107-10) 84... 

GiuUan D, Vaca K, Noonan CA (1990) Secretion of neurotoxins by mononuclear phagocytes infected with HIV-1. Science 250 1593-1596... 

Gendelman HE, Persidsky Y (2005) Infections of the nervous system. Lancet Neurol 4 12-13 Gerard C, Rollins BJ (2001) Chemokines and disease. Nat Immunol 2 108-115 Gitter BD, Cox LM, Rydel RE, May PC (1995) Amyloid beta peptide potentiates cytokine secretion by interleukin-1 beta-activated human astrocytoma cells. Proc Natl Acad Sci USA 92 10738-10741 GiuUan D, Yu J, Li X, Tom D, Li J, Wendt E, Lin SN, Schwarcz R, Noonan C (1996) Study of receptor-mediated neurotoxins released by HIV-1-infected mononuclear phagocytes found in human brain. J Neurosci 16 3139-3153... 

Gartner S, Markovits P, Markovitz DM, Kaplan MH, Gallo RC, Popovic M (1986) The role of mononuclear phagocytes in HTLV-III/LAV infection. Science 233(4760) 215-219 Glaser R, Kiecolt-Glaser JK (2005) Stress-induced immune dysfunction Implications for health. Nat Rev Immunol 5(3) 243-251... 

Perez-Casanova A, Noel RJ Jr, Rivera-Amill V, Husain K, Kumar A (2007) Morphine-mediated deterioration of oxidative stress leads to rapid disease progression in SIV/SHIV-infected macaques. AIDS Res Hum Retroviruses 23 1004-1007 Persidsky Y, Gendelman HE (2003) Mononuclear phagocyte immunity and the neuropathogenesis of HIV-1 infection. J Leukoc Biol 74 691-701... 

THAI S F, LEWIS J G, WILLIAMS R B, JOHNSON S P And ADAMS D O (1995) Effects of oxidized LDL on mononuclear phagocytes inhibition of induction of four inflammatory c)dokine gene RNAs, release of NO, and cytolysis of tumor cells Journal of Leukocyte Biology 57, 427-33. 

Giulian, D. and Robertson, C, (1990). Inhibition of mononuclear phagocytes reduces ischemic injury in the spinal cord. Ann. Neurol, 27, 33-42. 

The mature vitreous contains a class of mononuclear phagocytic cells called hyalocytes (Balzas and Delinger, 1984). These cells are generally embedded in the vitreous humour 20-50 /tM away from the basal lamina, forming a single layer of scattered cells. In the developing eye they are located more centrally and are capable of synthesizing the main solid constituents of the vitreous gel. 

Verspaget, H. and Beeken, W. (1985). Mononuclear phagocytes in the gastrointestinal tract. Acta Chir. Scand. Suppl. 525, 113-126. 

Davis, J.B., McMurray, H.F. and Schubert, D. (1992). The amyloid beta-protein of Alzheimer s disease is chemotactic for mononuclear phagocytes. Biochem. Biophys. Res. Commun. 189, 1096-1100. 

Sironi, M Munoz, C., Pollicino, T Siboni, A., Sciacca, F. L Bernasconi, S., Vecchi,A., Colot-ta, F and Montavani, A., Divergent effects of interleukin-10 on cytokine production by mononuclear phagocytes and endothelial cells. Eur. J. Immunol. 23,2692-2695 (1993). 

Figure 8.1 Body iron stores and daily iron exchange. The figure shows a schematic representation of the routes of iron movement in normal adult male subjects. The plasma iron pool is about 4 mg (transferrin-bound iron and non-transferrin-bound iron), although the daily turnover is over 30 mg. The iron in parenchymal tissues is largely haem (in muscle) and ferritin/haemosiderin (in hepatic parenchymal cells). Dotted arrows represent iron loss through loss of epithelial cells in the gut or through blood loss. Numbers are in mg/day. Transferrin-Tf haemosiderin - hs MPS - mononuclear phagocytic system, including macrophages in spleen and Kupffer cells in liver.

Morgan, C.J., and Stanley, E.R. (1984) Chemical crosslinking of the mononuclear phagocyte specific growth factor CSF-1 to its receptor at the cell surface. Biochem. Biophys. Res. Comm. 119, 35—41. 

Leukocytes have been subclassified into three families mononuclear phagocytes, lymphocytes and granulocytes. These can be differentiated from each other on the basis of their interaction with a dye known as Romanowsky stain (Figure 8.B1). 

A number of cells, including cytotoxic T lymphocytes, NK cells, and mononuclear phagocytic cells, are endowed with cytotoxic abilities and thus mediate important immunosurveillance mechanisms against neoplastic cells and viral infections. In immune-compromised hosts, a correlation has been observed between low NK cell activity and morbidity [22-25] or the incidence and severity of upper respiratory tract infections [24],... 

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