| Autor: |
Alam SM; Department of Medicine, Duke Human Vaccine Institute, Duke University School of Medicine, RP1 Circuit Drive, Durham, NC 27710, USA. alam0004@mc.duke.edu, McAdams M, Boren D, Rak M, Scearce RM, Gao F, Camacho ZT, Gewirth D, Kelsoe G, Chen P, Haynes BF |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of immunology (Baltimore, Md. : 1950) [J Immunol] 2007 Apr 01; Vol. 178 (7), pp. 4424-35. |
| DOI: |
10.4049/jimmunol.178.7.4424 |
| Abstrakt: |
Two neutralizing human mAbs, 2F5 and 4E10, that react with the HIV-1 envelope gp41 membrane proximal region are also polyspecific autoantibodies that bind to anionic phospholipids. To determine the autoantibody nature of these Abs, we have compared their reactivities with human anti-cardiolipin mAbs derived from a primary antiphospholipid syndrome patient. To define the role of lipid polyreactivity in binding of 2F5 and 4E10 mAbs to HIV-1 envelope membrane proximal epitopes, we determined the kinetics of binding of mAbs 2F5 and 4E10 to their nominal gp41 epitopes vs liposome-gp41 peptide conjugates. Both anti-HIV-1 mAbs 2F5 and 4E10 bound to cardiolipin with K(d) values similar to those of autoimmune anti-cardiolipin Abs, IS4 and IS6. Binding kinetics studies revealed that mAb 2F5 and 4E10 binding to their respective gp41 peptide-lipid conjugates could best be defined by a two-step (encounter-docking) conformational change model. In contrast, binding of 2F5 and 4E10 mAbs to linear peptide epitopes followed a simple Langmuir model. A mouse mAb, 13H11, that cross-blocks mAb 2F5 binding to the gp41 epitope did not cross-react with lipids nor did it neutralize HIV-1 viruses. Taken together, these data demonstrate the similarity of 2F5 and 4E10 mAbs to known anti-cardiolipin Abs and support the model that mAb 2F5 and 4E10 binding to HIV-1 involves both viral lipid membrane and gp41 membrane proximal epitopes. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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