Related Experiment Videos
MHC class II-mediated T cell response to DNA
1Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel.
Cellular Immunology
|October 10, 1996
Summary
DNA directly activates T cells by binding to MHC class II molecules, a crucial step in autoimmune diseases like lupus. This finding reveals DNA's direct role in T cell regulation and autoimmunity.
Area of Science:
- Immunology
- Autoimmunity
- Molecular Biology
Background:
- Anti-DNA antibodies are hallmarks of autoimmune diseases such as systemic lupus erythematosus.
- The mechanism of T cell activation by DNA, a prerequisite for antibody production, remained unclear, as DNA presentation by major histocompatibility complex (MHC) molecules was not previously demonstrated.
Purpose of the Study:
- To investigate the direct role of DNA in T cell activation and its presentation by MHC molecules.
- To elucidate the involvement of DNA in autoimmune processes.
Main Methods:
- T cells from mice immunized with anti-DNA antibodies were isolated.
- DNA-specific T cell proliferation assays were performed.
- Antigen-presenting cells were used to study DNA presentation, with inhibition assays employing anti-Ia antibodies and H-2 haplotype-restricted peptides.
Main Results:
- Demonstrated DNA-specific T cell activation in response to DNA.
- Showed that DNA presentation by antigen-presenting cells is mediated by MHC class II molecules.
- Inhibition studies confirmed the MHC class II-restricted presentation of DNA.
Conclusions:
- DNA can be directly presented by MHC class II molecules to activate T cells.
- This DNA presentation plays a direct role in the regulation of T cells.
- The findings suggest a direct role for DNA in the pathogenesis of autoimmune diseases.