| Autor: |
Dennert Kate, Kozinski Karen, Khatri Bhupendra O, Tector Matt, Oaks Martin K |
| Jazyk: |
angličtina |
| Rok vydání: |
2009 |
| Předmět: |
|
| Zdroj: |
BMC Immunology, Vol 10, Iss 1, p 51 (2009) |
| Druh dokumentu: |
article |
| ISSN: |
1471-2172 |
| DOI: |
10.1186/1471-2172-10-51 |
| Popis: |
Abstract Background CTLA-4 was initially described as a membrane-bound molecule that inhibited lymphocyte activation by interacting with B7.1 and B7.2 molecules on antigen presenting cells. Alternative splicing of mRNA encoding the CTLA-4 receptor leads to the production of a molecule (sCTLA-4) that lacks a membrane anchor and is therefore secreted into the extracellular space. Despite studies finding that people with autoimmune disease more frequently express high levels of sCTLA-4 in their blood than apparently healthy people, the significance of these findings is unclear. Methods Molecules isolated from blood using CTLA-4 specific antibodies were analyzed with ligand binding assays, mass spectroscopy, and biochemical fractionation in an effort to increase our understanding of CTLA-4 immunoreactive material. Results Mass spectroscopy analysis of the molecules recognized by multiple CTLA-4-specific antibodies failed to identify any CTLA-4 protein. Even though these molecules bind to the CTLA-4 receptors B7.1 and B7.2, they also exhibit properties common to immunoglobulins. Conclusion We have identified molecules in blood that are recognized by CTLA-4 specific antibodies but also exhibit properties of immunoglobulins. Our data indicates that what has been called sCTLA-4 is not a direct product of the CTLA-4 gene, and that the CTLA-4 protein is not part of this molecule. These results may explain why the relationship of sCTLA-4 to immune system activity has been difficult to elucidate. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
|
