The effects of eosinophil-granule major basic protein on lung-macrophage superoxide anion generation

J Allergy Clin Immunol. 1992 Mar;89(3):746-52. doi: 10.1016/0091-6749(92)90383-d.

Abstract

The effects of major basic protein (MBP) on superoxide anion release in vitro from normal guinea pig (GP) alveolar macrophages (AM) was determined. Native MBP at 55 micrograms/ml had an immediate effect (reduction) on phorbol myristate acetate (PMA)-induced (p less than 0.01) and spontaneous (p = 0.055) superoxide (O2-) release by GP AMs. A similar effect was not observed from AMs incubated for 24 hours with MBP before assessment of O2- release. However, after AMs were incubated with MBP for 48 hours, again there was a significant reduction observed in both PMA-induced (p = 0.01) and spontaneous (p = 0.002) O2- release compared to that of control cultures. The immediate effect of MBP on AM O2- release was not due to cytotoxicity of MBP for AM. In contrast, the effect observed after 48 hours of culture was due, in part, to a direct toxic effect of the MBP on the AM because the viability of AM cultured for 48 hours with MBP (55 micrograms/ml) was 63.6% +/- 13% compared to the viability of control cultures of AM that was 83.9% +/- 7%; p = 0.03. The effect of MBP on AM O2- release at 48 hours was progressive over concentrations ranging from 2 to 55 micrograms/ml. These data suggest that native MBP can affect adversely PMA-induced and spontaneous release of O2- by GP AMs and that this effect depends only in part on the cytotoxic properties of MBP.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Animals
  • Anions
  • Blood Proteins / isolation & purification
  • Blood Proteins / pharmacology*
  • Cells, Cultured / drug effects
  • Cells, Cultured / metabolism
  • Eosinophil Granule Proteins
  • Eosinophils / metabolism*
  • Guinea Pigs
  • Humans
  • Macrophages, Alveolar / drug effects*
  • Macrophages, Alveolar / metabolism
  • Oxygen / metabolism
  • Ribonucleases*
  • Superoxides / metabolism*
  • Time Factors

Substances

  • Anions
  • Blood Proteins
  • Eosinophil Granule Proteins
  • Superoxides
  • Ribonucleases
  • Oxygen