Altered turnover and synthesis rates of lung surfactant following thoracic irradiation

Agreement in surfactant measurements of sputum induced with hypertonic and normal saline

“…Indeed Wright and colleagues have recently described altered phospholipid composition and function of airway (sputum) but not alveolar (BAL fluid) surfactant in adults with stable asthma 20 . Animal studies have shown progressively increased DPPC levels in response to chronic lung injury 8,9 . Acute suppression of airway surfactant production occurs as a response to lung injury, 7,21 and, following injury increased DPPC levels are found 8,9 , 22 .…”

“…The major constituent of surfactant that effects the barrier properties is dipalmitoyl phosphatidycholine (DPPC) 5 . Phospholipid levels of surfactant are known to be altered in animals with experimentally induced lung disease and processes such as toxin‐induced injury, 6 sepsis‐induced respiratory failure, 7 chronic sulphur dioxide exposure, 8 and thoracic irradiation 9 . The measurement of DPPC in induced sputum in humans may be useful for further research purposes.…”

“…5 Phospholipid levels of surfactant are known to be altered in animals with experimentally induced lung disease and processes such as toxin-induced injury, 6 sepsis-induced respiratory failure, 7 chronic sulphur dioxide exposure, 8 and thoracic irradiation. 9 The measurement of DPPC in induced sputum in humans may be useful for further research purposes. We have recently shown a relationship between sputum DPPC levels and eosinophilic inflammation in the airways of children with stable asthma.…”

Perinatal changes in lung surfactant calcium measured in situ.

“…Deficiency or dysfunction of surfactant results in severe lung disease, the best example of which is respiratory distress syndrome (RDS)' of University ofPennsylvania the premature newborn, in which an absolute deficiency of surfactant material exists due to immaturity ofthe type II cells (2). Other surfactant deficiency or dysfunction states are being increasingly recognized (3,4).…”

“…The calcium dependency of TM may be based on one of the major surfactant-associated proteins, SP-A, which is a calcium-binding protein (Kd = 1-2 mM) and which has been shown to aggregate into a multimolecular form in the presence of calcium (9,10). Further, adsorption of the surfactant material in vitro also has a calcium dependency (1 [1][2][3][4][5][6][7][8][9][10][11][12][13], and thus the lipid-protein complex in the form ofTM has been proposed to be an important intermediate between the secreted material and the functional interfacial form of surfactant (7,14).…”