Pharmaceutical Research

, Volume 22, Issue 12, pp 1997–2006

Structural Characterization and Immunogenicity in Wild-Type and Immune Tolerant Mice of Degraded Recombinant Human Interferon Alpha2b

  • Suzanne Hermeling
  • Liliana Aranha
  • J. Mirjam A. Damen
  • Monique Slijper
  • Huub Schellekens
  • Daan J. A. Crommelin
  • Wim Jiskoot
Research Paper

DOI: 10.1007/s11095-005-8177-9

Cite this article as:
Hermeling, S., Aranha, L., Damen, J.M.A. et al. Pharm Res (2005) 22: 1997. doi:10.1007/s11095-005-8177-9

Purpose

This study was conducted to study the influence of protein structure on the immunogenicity in wild-type and immune tolerant mice of well-characterized degradation products of recombinant human interferon alpha2b (rhIFNα2b).

Methods

RhIFNα2b was degraded by metal-catalyzed oxidation (M), cross-linking with glutaraldehyde (G), oxidation with hydrogen peroxide (H), and incubation in a boiling water bath (B). The products were characterized with UV absorption, circular dichroism and fluorescence spectroscopy, gel permeation chromatography, reverse-phase high-pressure liquid chromatography, sodium dodecyl sulfate polyacrylamide gel electrophoresis, Western blotting, and mass spectrometry. The immunogenicity of the products was evaluated in wild-type mice and in transgenic mice immune tolerant for hIFNα2. Serum antibodies were detected by enzyme-linked immunosorbent assay or surface plasmon resonance.

Results

M-rhIFNα2b contained covalently aggregated rhIFNα2b with three methionines partly oxidized to methionine sulfoxides. G-rhIFNα2b contained covalent aggregates and did not show changes in secondary structure. H-rhIFNα2b was only chemically changed with four partly oxidized methionines. B-rhIFNα2b was largely unfolded and heavily aggregated. Nontreated (N) rhIFNα2b was immunogenic in the wild-type mice but not in the transgenic mice, showing that the latter were immune tolerant for rhIFNα2b. The anti-rhIFNα2b antibody levels in the wild-type mice depended on the degradation product: M-rhIFNα2b > H-rhIFNα2b ∼ N-rhIFNα2b ≫ B-rhIFNα2b; G-rhIFNα2b did not induce anti-rhIFNα2b antibodies. In the transgenic mice, only M-rhIFNα2b could break the immune tolerance.

Conclusions

RhIFNα2b immunogenicity is related to its structural integrity. Moreover, the immunogenicity of aggregated rhIFNα2b depends on the structure and orientation of the constituent protein molecules and/or on the aggregate size.

Key Words

aggregatesimmune toleranceimmunogenicityinterferon alpha2protein structuretransgenic mice

Abbreviations

ABTS

2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)

BSA

bovine serum albumin

CD

circular dichroism

DLS

dynamic light scattering

DTT

dithiothreitol

ELISA

enzyme-linked immunosorbent assay

ESI-ToF

electrospray ionization-time of flight

GPC

gel permeation chromatography

hIFNα2

human interferon alpha2

i.p.

intraperitoneally

MALDI-ToF/ToF

matrix-assisted laser desorption ionization time of flight/time of flight

PAGE

polyacrylamide gel electrophoresis

PB

sodium phosphate buffer, pH 7.2

PBS

phosphate-buffered saline

rhIFNα2b

recombinant human interferon alpha2b

RP-HPLC

reverse-phase high-pressure liquid chromatography

s.c.

subcutaneously

SDS

sodium dodecyl sulfate

SPR

surface plasmon resonance

TFA

trifluoroacetic acid

Copyright information

© Springer Science + Business Media, Inc. 2005

Authors and Affiliations

  • Suzanne Hermeling
    • 1
    • 2
  • Liliana Aranha
    • 2
  • J. Mirjam A. Damen
    • 3
  • Monique Slijper
    • 3
  • Huub Schellekens
    • 1
  • Daan J. A. Crommelin
    • 2
  • Wim Jiskoot
    • 2
  1. 1.Central Laboratory Animal InstituteUtrecht UniversityUtrechtThe Netherlands
  2. 2.Department of Pharmaceutics, Faculty of Pharmaceutical SciencesUtrecht Institute for Pharmaceutical Sciences (UIPS)UtrechtThe Netherlands
  3. 3.Department of Biomolecular Mass SpectrometryUtrecht Institute for Pharmaceutical Sciences (UIPS) and Bijvoet Center for Biomolecular ResearchUtrechtThe Netherlands