Application of fluorescent monocytes for probing immune complexes on antigen microarrays

PLoS One. 2013 Sep 5;8(9):e72401. doi: 10.1371/journal.pone.0072401. eCollection 2013.

Abstract

Microarrayed antigens are used for identifying serum antibodies with given specificities and for generating binding profiles. Antibodies bind to these arrayed antigens forming immune complexes and are conventionally identified by secondary labelled antibodies.In the body immune complexes are identified by bone marrow derived phagocytic cells, such as monocytes. In our work we were looking into the possibility of replacing secondary antibodies with monocytoid cells for the generation of antibody profiles. Using the human monocytoid cell line U937, which expresses cell surface receptors for immune complex components, we show that cell adhesion is completely dependent on the interaction of IgG heavy chains and Fcγ receptors, and this recognition is susceptible to differences between heavy chain structures and their glycosylation. We also report data on a possible application of this system in autoimmune diagnostics.Compared to secondary antibodies, fluorescent monocytesas biosensors are superior in reflecting biological functions of microarray-bound antibodies and represent an easy and robust alternative for profiling interactions between serum proteins and antigens.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Immobilized / chemistry
  • Autoantigens / chemistry
  • Autoantigens / immunology
  • Autoantigens / metabolism*
  • Cell Adhesion
  • Cell Line, Tumor
  • Complement System Proteins / metabolism
  • Fluorescent Dyes / chemistry
  • Humans
  • Immunoglobulin G / blood*
  • Immunoglobulin M / blood
  • Lupus Erythematosus, Systemic / blood
  • Lupus Erythematosus, Systemic / immunology
  • Monocytes / immunology*
  • Protein Array Analysis / methods*
  • Protein Binding
  • Receptors, IgG / metabolism

Substances

  • Antibodies, Immobilized
  • Autoantigens
  • Fluorescent Dyes
  • Immunoglobulin G
  • Immunoglobulin M
  • Receptors, IgG
  • Complement System Proteins

Grant support

This work was supported by KMOP 1.1.1-08/1-2008-028 grant from the National Development Agency, OTKA PD104779 and K104838 grants and by the Hungarian Academy of Sciences. KP is supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.