MHC molecules protect T cell epitopes against proteolytic destruction

TY - JOUR

T1 - MHC molecules protect T cell epitopes against proteolytic destruction

AU - Mouritsen, S

AU - Meldal, M

AU - Werdelin, O

AU - Buus, Anette Stryhn

AU - Buus, S

N1 - Keywords: Amino Acid Sequence; Animals; Cell-Free System; Endopeptidases; Epitopes; Histocompatibility Antigens Class II; Mice; Molecular Sequence Data; Muramidase; Peptides; Protein Binding; T-Lymphocytes

PY - 1992

Y1 - 1992

N2 - There is a subtle duality in the role of proteolytic enzymes in Ag processing. They are required to fragment protein Ag ingested by APC. However, prolonged exposure to proteolytic enzymes may lead to a complete degradation of the Ag, leaving nothing for the T cell system to recognize. What ensures that some of the Ag is salvaged? Using a cell-free system we demonstrate that an Ag fragment, once bound to a MHC class II molecule, is effectively protected against proteolytic destruction by cathepsin B and pronase E. The bound fragment, however, can be modified by aminopeptidase N. We suggest that MHC class II molecules play an important regulatory role in the physiologic processing of Ag.

AB - There is a subtle duality in the role of proteolytic enzymes in Ag processing. They are required to fragment protein Ag ingested by APC. However, prolonged exposure to proteolytic enzymes may lead to a complete degradation of the Ag, leaving nothing for the T cell system to recognize. What ensures that some of the Ag is salvaged? Using a cell-free system we demonstrate that an Ag fragment, once bound to a MHC class II molecule, is effectively protected against proteolytic destruction by cathepsin B and pronase E. The bound fragment, however, can be modified by aminopeptidase N. We suggest that MHC class II molecules play an important regulatory role in the physiologic processing of Ag.

M3 - Journal article

C2 - 1381392

SN - 0022-1767

VL - 149

SP - 1987

EP - 1993

JO - Journal of Immunology

JF - Journal of Immunology

IS - 6

ER -