These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Destructive proteolysis by cysteine proteases in antigen presentation of ovalbumin.
    Author: Rodriguez GM, Diment S.
    Journal: Eur J Immunol; 1995 Jul; 25(7):1823-7. PubMed ID: 7621859.
    Abstract:
    Most native antigens require digestion by acidic proteases in order to be recognized in the context of major histocompatibility complex class II by T helper cells (Th). We have studied the roles of three different acidic proteases, cathepsin D, cathepsin B and cathepsin L, in the processing of ovalbumin (OVA) for presentation in the context of I-Ad. We report that digestion of OVA in vitro with the aspartyl protease cathepsin D generates the epitope OVA322-336, which is recognized by I-Ad-restricted OVA-specific Th in the presence of paraformaldehyde-fixed antigen-presenting cells (APC). In contrast, digestion of OVA with the cysteine proteases cathepsin B and L not only failed to generate an epitope, but also destroyed OVA322-336. In the presence of fixed APC expressing I-Ad. OVA322-336 was protected from destructive proteolysis by cathepsin L. These results illustrate the dependence of epitope selection on the intracellular proteolytic environment in APC, and suggest that mechanisms must exist for protection of epitopes from destructive proteolysis in the processing compartments.
    [Abstract] [Full Text] [Related] [New Search]