Macrophages, acid phosphatase

Decreased lysozyme, acid phosphatase, and /3-glucuronidase activity in alveolar macrophages (appears to be linearly related to dose up to 1 ppm)... 

Exposure of animals to ozone lowers their resistance to bacterial infection of the limgs ( ). Ozone exposure also causes changes in the properties of material that can be lavaged from the lungs there is inactivation of the enzymes acid phosphatase, 3-glucuronidase and lysozyme, and there is a tendency for these enzymes to have been released from the alveolar macrophage cells ( ). vivo inactivation of lung lysozyme has... 

A18. Axline, S. G., Isozymes of acid phosphatase in normal and Calmette-Gu4rin bacillus-induced rabbit alveolar macrophages. J. Exp. Med. 128, 1031-1048 (1968). 

Purple acid phosphatases. Diiron-tyrosinate proteins with acid phosphatase activity occur in mammals, plants, and bacteria. Most are basic glycoproteins with an intense 510- to 550-nm light absorption band. Well-studied members come from beef spleen, from the uterine fluid of pregnant sows (uteroferrin), and from human macrophages and osteoclasts. " " One of the two iron atoms is usually in the Fe(III) oxidation state, but the second can be reduced to Fe(II) by mild reductants such as ascorbate. This half-reduced form is enzymatically active and has a pink color and a characteristic EPR signal. Treatment with oxidants such as H2O2 or hexacyannoferrate (III)... 

Moss DW. Changes in enzyme expression related to differentiation and regulatory factors the acid phosphatase of osteoclasts and other macrophages. Clin Chim Acta 1992 209 131-8. 

In vitro studies have shown that TRAcP 5b isoform remains intracellularly in macrophages and dendritic cells which only secrete the TRAcP 5a isoform [25]. Therefore, for clinical determinations it is assumed that the tartrate-resistant acid phosphatase activity associated with bone resorbing osteoclasts derives only from the TRAcP 5 b isoform. 

Acid phosphatase (EC 3.1.3.2) is the classic lysosomal enzyme. The lead substitution method has localised acid phosphatase in the phagosomes of macrophages (Cohn and Wiener 1963) and can be used for electron microscopy. 

Tartrate-resistant acid phosphatase is characterised for activated macrophages (Efstratiadis and Moss 1985). Tartrate-resistant acid phosphatase contains a binuclear iron centre that has been shown to generate reactive oxygen species. Raisa-nen et al. (2001) showed that the murine macrophage-like cell line RAW-264 overexpressing tartrate-resistant acid phosphatase produced elevated levels of hydroxyl radicals compared to parental cells. 

Nash et al. (1966) synthesised another compound, polyvinylpyridinioacetic acid, which has even greater hydrogen bonding capacity than poly-2-vinylpyridine-l-oxide and very efficiently protects macrophages from silica toxicity. This protection was confirmed by Sakabe and Koshi (1967), who also showed that it prevents the increase in acid phosphatase in macrophages following exposure to quartz particles < 2 pm in diameter. However, polybetaine was slightly more active than poly-2-vinylpyridine-1 - oxide. 

In rats infected with aerosols of Staphylococcus aureus and then exposed for 5 h to 2.5 ppm of ozone, bacterial ingestion and clearance by alveolar macrophages were impaired due to the absence of lysosomal acid phosphatase and P-glucuronidase activities in those cells subjected to the dual insults (Goldstein et al. 1978). 

Alveolar macrophages obtained by bronchoalveolar lavage from 25 silicotic patients under the electron microscope showed silica particles, activated nuclei, autophagic vacuoles and destroyed cell organelles (Reisz et al. 1988). Lysosomal acid phosphatase activity was elevated as compared with healthy volunteers. 

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