Proteins Clara-cell

Clara cell protein (CC10, phospholipase A2inhibitor) Inducible cyclooxygenase (COX-2)... 

Lesur O, Bernard AM, Begin RO. 1996. Clara cell protein (CC-16) and surfactant-associated protein A (SP-A) in asbestos-exposed workers. Chest 109 467-474. 

Zomer G. Development of a chemiluminescence immunoassay for clara cell protein at sub-pM levels. In Case JF, Herring PJ, Robison BH, Haddock SHD, Kricka LJ, Stanley PE, ed. Proceedings of the 11th International Symposium on Bioluminescence and Chemiluminescence. Singapore World Scientific, 2001 377-80. 

Clara cell protein CC16 is a potential biomarker for exposure to MMT, because the protein decreases in both BALE and serum following MMT exposure (Halateket al. 1998 Bernard and Hermans 1997), possibly due to decreased synthesis and/or protein secretion due to loss of producing cells (Halatek et al. 1998). The protein can be quantified in serum or urine, but no dose-response studies on the potential biomarker have been performed. 

Halatek T, Hermans C, Broeckaert F, et al. 1998. Quantification of Clara cell protein in rat and mouse biological fluids using a sensitive immunoassay. Fur Respir J 11 726-733. 

Thyroid transcription factor-1 thyroid transcription factor-1 (TTF-1) is a tissue-specific transcription factor and a member of the homeodomain transcription family, expressed selectively in thyroid follicular epithelial cells in addition to thyroid C cells, diencephalon cells and epithelial cells of the lung, namely in type II alveolar cells and in non-ciliated bronchiolar epithelial cells (Clara cells). TTF-1 is a transcription factor regulating the transcription of thyroglobulin and thyroid peroxidase in follicular epithelium and surfactant in alveolar cells as well as Clara cell protein. 

Halatek et al. (2000) found that the decrease in serum Clara cell protein of shipyard welders chronically exposed to manganese contained in welding fumes correlated negative with welding fume levels, expressed by ambient air Mn concentration (r = 0.47). Moreover, reduced synthesis and/or removal of Clara cell protein by the Clara cells negatively correlated with Mn level in blood (r = 0.52). On the other hand, in heavily exposed welding fume workers (> 1 mg Mn/m ), increased serum Clara cell protein levels were observed, which correlated positively with Mn air levels (r = 0.85) and Mn concentrations in urine (r = 0.38). 

Polish children (N = 112 total exposed N = 62 controls N = 50) Exposed PbB mean = 13.3 Lg/dl control mean = 3.9 Pg/dl 29 urinary or serum markers for nephron function Increased 32-microglobulin and Clara cell protein with increased PbB Fels et al. (1998)... 

Zhang L, Whitsett JA, Stripp BR (1997) Regulation of Clara cell secretory protein gene transcription by thyroid transcription factor-1. Biochim Biophys Acta 1350(3) 359-367... 

The elucidation of the mechanism has revealed that this specificity is due to a requirement for metabolic activation for which the Clara cell is particularly suited. Thus, early studies using radiolabeled 4-ipomeanol found that the compound was localized particularly in the lungs (when expressed as nmol g-1 wet weight of tissue), and was covalently bound to lung protein (Fig. 7.38). This binding was five times that seen in the liver. Furthermore, autoradiography revealed that the radiolabeled 4-ipomeanol was bound to the Clara cells,... 

C57BL / SD mice (male, female) Binding to protein complex in kidney and lung (Clara cells) [165]... 

MeS02 metabolites has been identified as a uteroglobulin-like protein present in the nonciliated bronchiolar (Clara) cells of the lung, also referred to as Clara cell secretary protein (CCSP) (Hard et al. 

Stripp BR, Lund J, Mango GW, etal. 1996. Clara cell secretory protein a determinant of PCB bioaccumulation in mammals. Am J Physiol 27LL656-L664. 

Thyroid transcription factor-1 (TTF-1), a nuclear tissue-specific protein transcription factor, is found in thyroid and thyroid tumors regardless of histologic type (except anaplastic type), as well as in lung carcinomas including adenocarcinomas (75%), non-small cell carcinomas (63%), neuroendocrine and small cell carcinomas (>90%), and squamous cell carcinomas (10%).258-258 Selectively expressed during embryogenesis in the thyroid, the diencephalon of the brain, and in respiratory epithelium, TTF-1 binds to and activates factors for surfactant protein derived from Clara cells.255 TTF-1 is rarely seen in carcinomas outside of the lung or thyroid... 

Vimentin is a 58-kD intermediate filament found predominantly in mesenchymal cells. However, vimentin is expressed in most spindle cell carcinomas and is reported by some to be expressed in a relatively high percentage of pulmonary adenocarcinomas. Thyroid transcription factor-1 (TTF-1), a 38- to 40-kD transcription factor member of the NKx2 family of home-odomain transcription factors, is expressed in thyroid and pulmonary epithelial cells. 49 TTF-1 binds to and activates the promoters for Clara cell secretory protein and surfactant proteins A, B, and As reported... 

In conclusion, the pulmonary toxicity of 4-ipomeanol seems to be due to metabolic activation of the furan ring, probably by epoxidation, catalysed by the cytochromes P-450 mono-oxygenases found in the Clara cell. The reactive intermediate binds to protein and possibly other macromolecules, initiating cellular necrosis followed by oedema. 

Hacked BP, Gitlm JD Cell-specihc expression of a Clara cell secretory protein-human growth hormone gene in the bronchiolar epithelium of transgenic mice Proc Natl Acad Sci USA 1992, 89 9079-9083... 

After an intratracheal instillation of benzo[a]py-rene (1 mg dissolved in 50 /tl tricaprylin), the Clara cell secretory protein dominant-negative mutant form of p53 transgenic mice was more susceptible... 

In primates, including man, the Clara cell has the features of a serous secretory cell that produces a protein-rich secretion. 

The prominent organelle in the cytoplasm of Clara cells from both wild-type strain 129 and Clara cell secretory protein -/- 129 mice is the smooth endoplasmic reticulum, which occupies about 20% of the cell cytoplasm (Strife et al. 2002). Despite the similarities in abundance there were two aspects of the smooth endoplasmic reticulum that differed markedly between both genotypes of mice. First, electron-dense material that was abundant within the lumen of smooth endoplasmic reticulum of Clara cells from wild-type mice was not as evident within the lumen of smooth endoplasmic reticulum of Clara cells from Clara cell secretory protein -/-129 mice. Second, Clara cells from Clara cell secretory protein -/- 129 mice were unique in that they possessed large concentric whorls of endoplasmic reticulum located within the apical portion of the cell. Membrane-bound inclusions, which appeared to he surrounded by at least one layer of endoplasmic reticulum, were found at the centre of these whorls and contained material of varying electron density and compaction. Some of these inclusions had the characteristics of mitochondria based on the presence of crista-like membrane inclusion. 

Clara cell secretory protein, known by a number of other names including urinary protein 1, uteroglo-bulin (Peri et al. 1995, Mukherjee et al. 1999), PCB-binding protein, and Clara cell 10 kDa protein (Mantile et al. 1993, Dodge et al. 1994, Singh and Katyal 1997) has been described as a multifunctional protein . 

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