Abstracts (complete list) - Wissenschaft Online

Stefanie Helm, Patrick Pankert, Stefanie Eikelmeier, Edward Shang, Hans Ulrich
Weltzien, Martina Schnoelzer, Hermann-Josef Thierse
Elements of the innate immune barrier: Proteomic
identification of allergen-protein interactions in the human
epidermis
Background:
Innate and adaptive molecular events underlying the most common contact
hypersensitivity towards heavy metal nickel (Ni) are still incompletely understood.
Aiming to identify primary allergen-protein interactions in the human epidermis, we
have chosen a specific immunoproteomic approach. Keratinocyte derived Ni-interacting
proteins were identified by mass spectrometric analysis and compared to previously
generated data of human antigen presenting cells.
Results:
To investigate molecular effects of Ni ions on human keratinocytes immobilized metal
ion affinity chromatography (IMAC) was used to isolate Ni-interacting proteins from
primary cell lysates. After 2-dimensional gel electrophoresis (2D-PAGE), laser scanning
of fluorescent protein gels (Fujifilm Europe, FLA 5100) followed by spot picking (Bruker
Daltonics, Proteineer II), trypsin digestion and mass spectrometric analysis (Bruker
Reflex II) more than 15 Ni-interacting epithelial proteins were identified in isolated
human keratinocytes. Comparative analysis from previous studies revealed differential
as well as similar Ni-interacting molecules in human B-cells, in-vitro generated DCs and
primary human keratinocytes. Among others, several heat shock proteins were
detected, which may be involved in initial cellular stress responses towards heavy metal
Ni.
Conclusion:
Immunoproteomic identification of Ni-interacting proteins in primary keratinocytes is an
important step in increasing the understanding of molecular mechanisms involved in the
development and the pathophysiology of human nickel allergy. Results indicate a pivotal
role for heat shock proteins and are discussed in light of Polly Matzinger's danger
theory.
(This work was supported in part by the Landesstiftung Baden-Wuerttemberg,
Germany, Forschungsprogramm “Allergologie” by grant P-LS-AL/26, and the European
Union, as part of the project Novel Testing Strategies for In Vitro Assessment of
Allergens (Sens-it-iv), LSHB-CT-2005 – 018681, www.sens-it-iv.eu).