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Purification of the Membrane Compartment for Endoplasmic Reticulum-associated Degradation of Exogenous Antigens in Cross-presentation
Published on: August 21, 2017
Cathepsin E in antigen-presenting Langerhans and interdigitating reticulum cells. Its possible role in antigen
1Dipartimento di Patologia Umana ed Ereditaria, I Facoltà di Medicina e Chirurgia, Università di Pavia ed I.R.C.C.S. Policlinico S. Matteo, Italy.
Cathepsin E, an aspartic proteinase, is found in skin and lymph node immune cells like Langerhans cells, but not macrophages. Its location suggests a role in antigen processing.
Area of Science:
- Immunology
- Cell Biology
- Biochemistry
Background:
- Cathepsin E is an aspartic proteinase.
- Its cellular distribution and function are not fully understood.
Purpose of the Study:
- To investigate the presence and localization of cathepsin E in immune cells.
- To explore the potential role of cathepsin E in antigen processing.
Main Methods:
- Rabbit anti-human cathepsin E serum was used for detection.
- Immunoblotting was performed on tissue extracts.
- Electron immunocytochemistry with protein A gold technique was employed for ultrastructural localization.
Main Results:
- Cathepsin E was detected in Langerhans cells (skin), interdigitating reticulum cells (lymph nodes, spleen), and histiocytosis X cells.
- Cathepsin E was notably absent in macrophages.
- Immunoblotting confirmed cathepsin E in skin and lymph node extracts.
- Electron immunocytochemistry localized cathepsin E to the endoplasmic reticulum and endosomal vesicles, including Birbeck bodies, in interdigitating and Langerhans cells.
Conclusions:
- Cathepsin E is present in specific immune cells involved in antigen presentation.
- The localization of cathepsin E within endosomal compartments suggests a role in antigen processing.
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