Anti-human platelet antigen-1α immunoglobulin G preparation intended to prevent fetal and neonatal alloimmune thrombocytopenia
Permanent lenke
https://hdl.handle.net/10037/10233Dato
2016-09-14Type
Journal articleTidsskriftartikkel
Peer reviewed
Forfatter
Weng, Ying-Jan; Husebekk, Anne; Skogen, Bjørn Ragnar; Killie, Mette Kjær; Lin, Liang-Tzung; Burnouf, ThierrySammendrag
Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a severe disease that is
caused by maternal alloantibodies generated during pregnancy or at delivery as a result of
incompatibility between maternal and fetal human platelet antigens (HPAs) inherited from
the father. Antibody-mediated immune suppression using anti-HPA-1a immunoglobulins is
thought to be able to prevent FNAIT caused by HPA-1a. A fractionation process to prepare
anti-HPA-1a immunoglobulin (Ig) G (IgG) from human plasma was therefore developed.
Anti-HPA-1a plasma was obtained from volunteer mothers who underwent alloimmunization
against HPA-1a during a previous pregnancy. Plasma was cryoprecipitated and the
supernatant treated with caprylic acid and solvent/detergent (S/D), purified by chromatography,
nanofiltered, concentrated, and sterile-filtered. The anti-HPA-1a immunoglobulin fraction
was characterized for purity and safety. PAK12 and quantitative monoclonal antibody
immobilization of platelet antigen (MAIPA) assays were used to detect anti-HPA-1a IgG.
Hepatitis C virus (HCV) removal during nanofiltration was assessed by spiking experiments,
using cell culture-derived reporter HCV and luciferase analysis. The caprylic acid treatment
precipitated non-Ig proteins yielding a 90% pure Ig supernatant. S-HyperCel chromatography
of the S/D-treated supernatant followed by HyperCel STAR AX provided high IgG
recovery (>80%) and purity (>99.5%), and efficient IgA and IgM removal. Concentrations of
complement factors C3 and C4 were < 0.5 and < 0.4 mg/dL, respectively. The final IgG
could be nanofiltered on Planova 20N under conditions removing more than 3 log HCV
infectivity to baseline mock infection level, and concentrated to ca. 30 g/L. Proteolytic activity
and thrombin generation were low in the final fraction. The Pak12 and MAIPA assays
showed good recovery of anti-HPA-1a throughout the process. Clinical-grade HPA-1a IgG can be prepared using a process compliant with current quality requirements opening perspectives
for the prevention of FNAIT.
Beskrivelse
Copyright: © 2016 Weng et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any
medium, provided the original author and source are
credited.
DOI: 10.1371/journal.pone.0162973
DOI: 10.1371/journal.pone.0162973