Article Text

PDF

PS-280 Surface Film Fromation in Vitro By Infant And Therapeutic Surfactants: Role Of Surfactant Protein B
  1. O Danhaive1,
  2. C Chapin1,
  3. H Horneman1,
  4. PE Cogo2,
  5. PL Ballard1
  1. 1Pediatrics, University of California San Francisco, San Francisco, USA
  2. 2Cardiology, Bambino Gesu Children’s Hospital, Rome, Italy

Abstract

Background Essential surfactant properties include transfer to gas-liquid interface, reduction of surface tension and film replenishment during respiratory cycles.

Objective To compare component-specific film formation properties of infant and therapeutic surfactants.

Design/methods Using a multiwell fluorescence assay, we compared maximal fluorescence (Max), time to reach Max (tMax) and phospholipid concentration for ½ maximal signal (½Max) for calfactant (CAL), poractant (POR), beractant (BER), colfosceryl palmitate (COL), with surfactant from immature infants with RDS. Dose-response studies were performed for addition of SP-B, albumin and budesonide.

Results Max and ½Max values for CAL were higher/similar to those of rat surfactant. There were significant differences between CAL and other therapeutic surfactants for Max (CAL >COL >POR >BER) whereas ½Max were similar except for COL.

In surfactant from 39 infant tracheal aspirates, ½Max was inversely correlated with SP-B content (p = 0.001). Addition of SP-B to samples with low endogenous content (<0.1%) decreased ½Max in a dose-dependent way. Addition of 1.25% SP-B to BER (SP-B content 0.04%) increased Max by 324%. Addition of albumin to CAL (0.75 μg/μg PL) increased ½Max by 110% and reduced Max by 13%. By contrast, addition of budesonide to CAL at 2% and 10% increased Max by 51 ± 26% and 93 ± 19%, with no effect on ½Max.

Conclusions This assay reveals differences in film formation efficiency for therapeutic surfactants reflecting differences in SP-B content and lipid composition. Film formation by infant surfactant is strongly influenced by SP-B content. The findings support the key physiological role of SP-B and the safety of surfactant as anti-inflammatory drug vehicle.

Statistics from Altmetric.com

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.