Open AccessImmunological evidence and regulatory potential for cell‐penetrating antibodies in intravenous immunoglobulin
Author(s) -
Sali Aggeliki D,
Karakasiliotis Ioannis,
Evangelidou Maria,
Avrameas Stratis,
Lymberi Peggy
Publication year - 2015
Publication title -
clinical and translational immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.321
H-Index - 34
ISSN - 2050-0068
DOI - 10.1038/cti.2015.18
Subject(s) - antibody , autoantibody , cytoplasm , cell , immunology , intracellular , in vitro , splenocyte , in vivo , immunoglobulin g , chemistry , biology , microbiology and biotechnology , biochemistry
Anti‐DNA cell‐penetrating autoantibodies have been extensively studied in autoimmune but not in normal sera. We investigated herein the presence and properties of cell‐penetrating antibodies (CPAbs) in intravenous immunoglobulin (IVIg), a blood product of pooled normal human IgG. IVIg cell penetration was observed into various cell lines, as well as cells from several organs of mice injected intravenously with IVIg therapeutic dose. In all cell types examined in vitro and in vivo , intracellular IgG localized in the cytoplasm, in contrast to the nuclear accumulation of disease‐related CPAbs. IVIg was found to rapidly enter cells via an energy‐independent mode. The CPAb‐fraction was isolated and found to be polyreactive to nuclear and cytoplasmic components; although it corresponded to ~2% of IVIg, it accounted for its inhibitory effect on splenocyte activation. Investigation of IVIg cell penetration capacity provides insight into its mechanisms of action and may account for some of its beneficial effects in numerous diseases.