Details

Autor(en) / Beteiligte

• Kerblat, I
• Tongiani-Dahshan, S
• Aude-Garcia, C
• Villiers, M-B
• Drouet, C
• Marche, P N

Titel

Tetanus toxin L chain is processed by major histocompatibility complex class I and class II pathways and recognized by CD8 super(+) or CD4 super(+) T lymphocytes

Ist Teil von

• Immunology, 2000-06, Vol.100 (2), p.178-184

Erscheinungsjahr

2000

Link zum Volltext

Quelle

Wiley Online Library Journals Frontfile Complete

Beschreibungen/Notizen

• Tetanus toxin (TeNT) is a heterodimeric protein antigen, whose light chain (L) is translocated in the cytosol of neuronal target cells specifically to cleave its substrates, vesicle-associated membrane protein-2 (VAMP-2, or synaptobrevin) or cellubrevin. We report that the L chain behaves as a nominal antigen recognized by specific T-cell clones upon either class I- or II-restricted presentation. Three types of responses are observed: (i) a TeNT- and L-specific CD8 super(+) T-cell response, that can be inhibited in a dose-dependent manner by the proteasome inhibitor clasto-Lactacystin beta -lactone; (ii) a CD4 super(+) T-cell response specific for L but not TeNT, with recognition of a determinant processed in a chloroquine-sensitive and brefeldin A-resistant compartment; (iii) a CD4 super(+) T-cell response against both L and TeNT, with processing in a brefeldin A-sensitive compartment. The L chain processing was investigated in U937 cells by internalization and localization of L chain by separation of the cell content by differential centrifugation experiments. After incubation with TeNT or L chain in the presence of H chain, the L chain was predominantly distributed in the cytosolic fraction, whereas incubation with L alone led to localization in a lysosome/membrane fraction. The distribution of the TeNT L chain in both cytosolic and endocytic compartments of the antigen-presenting cell accounted for its processing by both class I and class II pathways. Furthermore, an epitope overlapping with the zinc-binding region was recognized by CD4 super(+) and CD8 super(+) T cells.