Relationship between dynamic viscoelasticity and biochemical parameters in whole sputum from patients with hypersecretory respiratory diseases.

To obtain suitable biochemical parameters for measuring the dynamic viscoelasticity of sputum, we examined the relationships of the dynamic viscoelasticity with the dry weight (DW) and the contents of fucose, a parameter of airway mucous glycoprotein (AMG), and total protein (TP) and major proteins in whole sputum. The DW and TP, albumin and IgG concentrations and elastase activity were higher in purulent sputum than in mucoid-mucopurulent sputum, but there was no significant difference in the concentrations of airway wall-derived substances, such as fucose and S-IgA in the two. In mucoid-mucopurulent sputum, the dynamic viscosity (eta') and elastic modulus (G'), an indicator of dynamic elasticity, were most closely correlated with the fucose concentration (r = +0.

[Lung surfactant apoprotein (LSP) content of sputum samples from patients with chronic airway diseases].

LSP contents of sputum samples from patients with chronic airway diseases were measured by an enzyme-linked immunosorbent assay (ELISA) kit which was designed by Kuroki et al to examine whether a substance identical to lung surfactant contained in alveolar lining layer, is also contained in respiratory tract fluid or not in the ELISA kit. One antibody to LSP was conjugated to peroxidase and another one to LSP was fixed onto a bead. A neo-anionic detergent, Triton X-100 and an anionic detergent, sodium dodecyl sulfate (SDS) were added to extraction medium to separate LSP from lung surfactant, and LSP reaction of sputum sample was maximal when the ratio of Triton X-100 to SDS was in range of 1 to 4.