High-molecular-weight surface-exposed proteins of Haemophilus influenzae mediate binding to macrophages. Academic Article uri icon

Overview

abstract

  • The molecular basis for direct bacteria-macrophage interactions that distinguishes nontypeable (NT) Haemophilus influenzae from type b organisms is not known. Because of similarities between filamentous hemagglutinin (FHA) adhesin of Bordetella pertussis and high-molecular-weight (HMW) proteins commonly expressed by NT H. influenzae, the role that HMW proteins play in determining NT H. influenzae-macrophage interactions was assessed. In tests with genetically engineered organisms, HMW protein-expressing bacteria bound significantly better than isogenic HMW protein-deficient bacteria to macrophages. HMW protein-dependent binding to macrophages is trypsin-sensitive, is independent of divalent cations, does not occur via the leukocyte integrin CD11b/CD18, and is not affected by galactose-containing carbohydrates. Organisms bound via HMW proteins remain largely extracellular and viable. Like FHA of Bordetella organisms, HMW proteins mediate binding of NT H. influenzae to macrophages. However, unlike the interaction determined by FHA, this interaction is characteristically one of adhesion and requires additional serum opsonization for efficient killing of bacteria by macrophages.

publication date

  • February 1, 1994

Research

keywords

  • Bacterial Proteins
  • Haemophilus influenzae
  • Macrophages

Identity

Scopus Document Identifier

  • 0028082259

Digital Object Identifier (DOI)

  • 10.1093/infdis/169.2.425

PubMed ID

  • 8106776

Additional Document Info

volume

  • 169

issue

  • 2