Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032285 (pneumonia)
 54,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hereditary surfactant protein B (SP-B) deficiency causes lethal neonatal respiratory disease associated with abnormalities in pulmonary surfactant proteins and lipids. SP-C, a 4-kDa hydrophobic protein produced from a 21-kDa precursor, cooperates with SP-B to enhance the surface active properties of surfactant phospholipids. Anti-proSP-C polyclonal antisera were produced against fusion proteins containing 1) the amino terminus (amino acids 1-20), 2) the region carboxy-terminal to the mature SP-C peptide (amino acids 58-77), and 3) full-length 197-amino acid proSP-C and were characterized using immunoprecipitation, Western blot, and immunohistochemical techniques. Western blot analysis of bronchoalveolar lavage and amniotic fluid from hereditary SP-B-deficient patients allowed identification of a 12-kDa form of SP-C that contained epitopes consistent with the amino-terminal and active peptide regions of SP-C (amino acids 1-57). The 12-kDa SP-C peptide was not detected in bronchoalveolar lavage from healthy adults or adults with alveolar proteinosis or pneumonia. We conclude that SP-B deficiency is associated with the aberrant processing and secretion of an immature SP-C peptide, which may contribute to the respiratory failure associated with hereditary SP-B deficiency.
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PMID:Aberrant processing of surfactant protein C in hereditary SP-B deficiency. 753 64

Investigation of the composition and significance of individual components of the surfactant indicated that besides phospholipids an important role is played also by surfactant proteins. They aid not only the reduction of the surface tension of the lungs (SP-B, SP-C), but serve also in regulation of surfactant secretion (SP-A) and in local defense and immune responses in the lungs (SP-A and SP-D). Impairments of surfactant were discovered not only in RDS, but also in cases of meconium aspiration, congenital diaphragmatic hernia, pneumonia, pulmonary edema, idiopathic fibrosis of the lungs, alveolar proteinosis, pneumothorax, and bronchial asthma. Therapy by means of exogenous surfactant was proved effective in therapy of RDS. Occasional cases of exogenous surfactant therapy in other pulmonary diseases are auspicious, it is necessary, though, to develop and produce a sufficient amount of exogenous surfactant of high quality and at an acceptable price and to find an optimal manner of surfactant administration into the lungs. A significant perspective is anticipated to utilization of intrapulmonary administration of the exogenous surfactant as a carrier of further active substances for local administration into the lungs. (Ref. 36.)
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PMID:[The pulmonary surfactant factor. Current knowledge, research trends and use in clinical practice]. 788 59

Respiratory failure secondary to acute lung inflammation is associated with quantitative and qualitative abnormalities of pulmonary surfactant. The surfactant-associated proteins (SP)-A, -B, and -C are critical for normal surfactant function, synthesis, and metabolism. Tumor necrosis factor-alpha (TNF-alpha), a primary mediator of acute lung inflammation, decreased SP gene expression in vitro (32, 34). In the present in vivo study, transient T cell activation and TNF-alpha release were initiated by intraperitoneal administration of anti-CD3 antibody 145-2C11. Serum TNF-alpha was elevated 2 h after injection of the antibody. SP-B and -C mRNA were decreased 12 and 24 h after antibody treatment. Intratracheal murine TNF-alpha also resulted in decreased SP-B and SP-C mRNA levels in the bronchiolar and alveolar epithelium of adult FVB/N mice, as demonstrated by S1 nuclease protection and in situ hybridization assays, despite minimal histological inflammation. SP-A mRNA was not significantly altered after anti-CD3 antibody and was only mildly decreased after TNF-alpha. As previously reported, intercellular adhesion molecule-1 mRNA was elevated after intratracheal TNF-alpha. SP insufficiency contributes to the pathogenesis of pulmonary diseases associated with increased TNF-alpha, such as adult respiratory distress syndrome and pneumonia (8). TNF-alpha-mediated decrease in SP gene expression may contribute to the surfactant dysfunction and atelectasis observed in inflammatory lung diseases.
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PMID:Tumor necrosis factor-alpha decreases surfactant protein B mRNA in murine lung. 896 4

Surfactant proteins SP-A and SP-D, members of the collectin family, have been shown to play a significant role in lung host defense. Both proteins selectively bind Pneumocystis carinii (PC) organisms and modulate the interaction of this pathogen with alveolar macrophages. We hypothesized that the expression and distribution of lung collectins SP-A and SP-D is altered by PC lung infection. PC organisms (2 x 10(5)) were inoculated intratracheally into C.B-17 scid/scid mice that do not require steroids for immunosuppression. Four weeks after inoculation, bronchoalveolar lavage (BAL) fluid was fractionated into three fractions-cell pellet, large aggregate (LA), and small aggregate (SA) surfactant-and each fraction was analyzed for the expression of surfactant components. In uninfected mice, the majority of SP-A (62% +/- 10%) was found in association with lipids in the LA fraction, while 55% +/- 14% of SP-D was distributed in the SA fraction. In contrast, both hydrophobic proteins SP-B and SP-C were associated exclusively with LA. PC infection resulted in major changes in the expression of all surfactant components. Total protein content of LA was unchanged by PC infection (115% +/- 18% of control), whereas SA protein content markedly increased (240% +/- 18% of control level, P <.001). In contrast, the phospholipid content of LA was significantly decreased (53% +/- 5% of control level, P <.001), whereas the SA phospholipid content of infected mice was increased (172% +/- 16% of control level, P <.001). By Western blotting, PC pneumonia (PCP) induced a 3-fold increase in the total alveolar SP-D protein that was reflected mainly in increases in SA SP-D (454% +/- 135% of control, P <.05). The total alveolar SP-A protein content was also increased in PCP because of a large increase in SP-A in SA (720% +/- 115% of control, P <.05); SP-A levels in LA were unchanged. The increases in lung collectin expression were selective, because PCP resulted in the down-regulation of both SP-B and SP-C in LA (5% +/- 2% and 13% +/- 2% of control, respectively, P <.001). We conclude that PCP induces marked elevations in alveolar collectin levels because of increased expression and accumulation of SP-A and SP-D protein in SA surfactant.
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PMID:Pneumocystis carinii pneumonia alters expression and distribution of lung collectins SP-A and SP-D. 1138 64