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Updated: Jul 13, 2026
08:51
Identification of Mouse and Human Antibody Repertoires by Next-Generation Sequencing
Published on: March 15, 2019
Evidence for a viral superantigen in humans
M Lafon1, M Lafage, A Martinez-Arends
1Unité de la Rage, Institut Pasteur, Paris, France.
Nature
|August 6, 1992
Summary
The rabies virus nucleocapsid acts as a superantigen, stimulating T lymphocytes. This finding identifies the first human viral superantigen, binding to HLA class II molecules.
Area of Science:
- Immunology
- Virology
- Molecular Biology
Background:
- Superantigens are microbial toxins that potently activate T lymphocytes by cross-linking T cell receptors with MHC class II molecules.
- Bacterial superantigens cause diseases like food poisoning and toxic shock syndrome.
- Viral superantigens are known in mice but have not been identified in humans.
Purpose of the Study:
- To identify and characterize a potential viral superantigen in humans.
- To investigate the role of the rabies virus nucleocapsid in immune responses.
Main Methods:
- Binding assays to assess interaction with HLA class II molecules.
- T lymphocyte proliferation assays to evaluate superantigen activity.
- Analysis of T lymphocyte V beta usage.
Main Results:
- The rabies virus nucleocapsid protein was identified as an exogenous superantigen.
- This superantigen specifically targets human T lymphocytes expressing V beta 8 sequences.
- The nucleocapsid binds to the alpha-chain of HLA class II molecules.
Conclusions:
- The rabies virus nucleocapsid functions as a human viral superantigen.
- This discovery has implications for understanding viral pathogenesis and T cell activation.
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