Autor: |
David, Smith, Roland, D'Argy, Mats, Nilsson, Ulf, Yrlid, James, de Jersey, Lars, Björck, Mary Jo, Wick |
Rok vydání: |
2004 |
Předmět: |
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Zdroj: |
Cellular microbiology. 6(7) |
ISSN: |
1462-5814 |
Popis: |
Protein L is an immunoglobulin (Ig)-binding protein produced by the Gram-positive bacterium Peptostreptococcus magnus that interacts with the variable region of Ig kappa light chains. The Ig light chain-binding capacity of protein L gives it the potential to interact with cells expressing surface Ig such as B cells. The present study was performed to address the in vivo trafficking of protein L at both the organ and the cellular level. Using the powerful technique of whole-body autoradiography in a murine model system, we demonstrate specific targeting of protein L to secondary lymphoid tissues in whole-animal analysis. The observed targeting depends on the capacity to interact with murine Ig, as tissue targeting was not apparent in mice given protein H, an Ig-binding protein produced by Streptococcus pyogenes with affinity for human but not murine Ig. Tissue targeting data were combined with flow cytometry analysis, which demonstrated the capacity of protein L to target and activate B lymphocytes in vivo. B cells targeted by protein L had increased surface expression of CD86 and MHC-II, and protein L was present in vacuolar compartments of B cells. Protein L did not bind T cells or natural killer cells but had some capacity to target dendritic cells and macrophages. The data show that protein L preferentially targets secondary lymphoid organs, and activates and is internalized by B cells in vivo. Furthermore, the observed tissue and cell targeting properties require an affinity for murine Ig. These data support the potential use of this Ig-binding protein as a targeting approach to deliver agents to defined cell populations in vivo. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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