Different abilities of two types of Fc gamma receptor on guinea-pig macrophages to trigger the phosphatidylinositol turnover

Mol Immunol. 1991 Apr-May;28(4-5):359-65.

Abstract

When exposed to hen ovalbumin (OA) complexes of IgG antibodies, guinea-pig macrophages were found to augment the phosphatidylinositol (PI) turnover. This response depended on the IgG isotype of antibodies used; OA complex of IgG2 antibody (OA gamma 2) triggered it about 3 times more effectively than did OA complex of IgG1 antibody (OA gamma 1). The inhibition experiments with monoclonal antibodies to Fc gamma 1/gamma 2R and Fc gamma 2R showed that Fc gamma 2R triggered activation of the PI turnover more intensively than did Fc gamma 1/gamma 2R. The same results were also obtained by the cross-linking of Fc gamma 2Rs or Fc gamma 1/gamma 2Rs by a combination of anti-mouse IgG F(ab')2 and anti-Fc gamma 2R F(ab')2 or anti-Fc gamma 1/gamma 2R F(ab')2. As the number of Fc gamma 2R molecules per macrophage is about one-half that of Fc gamma 1/gamma 2R molecules, the ability of Fc gamma 2R to trigger the response was found to be much greater than that of Fc gamma 1/gamma 2R. Despite this difference, neither the activity of Fc gamma 2R nor that of Fc gamma 1/gamma 2R to augment the PI turnover were affected by depletion of the intracellular Ca2+ by incubating the cells with Ionomycin and EGTA, and also by the treatment with pertussis toxin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigen-Antibody Complex / immunology
  • Antigens, Differentiation / classification
  • Antigens, Differentiation / physiology*
  • Calcium / pharmacology
  • Egtazic Acid / pharmacology
  • Guinea Pigs
  • Immunoglobulin G / metabolism
  • Immunoglobulin Isotypes / metabolism
  • In Vitro Techniques
  • Inositol Phosphates / metabolism
  • Macrophages / physiology*
  • Ovalbumin / immunology
  • Pertussis Toxin
  • Phosphatidylinositols / metabolism*
  • Receptors, Fc / classification
  • Receptors, Fc / physiology*
  • Receptors, IgG
  • Signal Transduction
  • Virulence Factors, Bordetella / pharmacology

Substances

  • Antigen-Antibody Complex
  • Antigens, Differentiation
  • Immunoglobulin G
  • Immunoglobulin Isotypes
  • Inositol Phosphates
  • Phosphatidylinositols
  • Receptors, Fc
  • Receptors, IgG
  • Virulence Factors, Bordetella
  • Egtazic Acid
  • Ovalbumin
  • Pertussis Toxin
  • Calcium