In a previous study, we identified that transferrin receptor (TfR) is the receptor utilized by hepatitis B virus (HBV) to enter T cells. We demonstrated that hepatitis B envelope antigen (H-BenvAg) is taken up by activated T cells via TfR, processed in endosomal compartments, and presented on class II molecules to specific CD4(+) T cell clones. Herein, we report that binding to soluble ferric Tf by HBenvAg is needed in TfR-mediated endocytosis. Accordingly, presentation of HBenvAg by activated T cells is not observed in serum-free medium and is restored by addition of soluble Tf. Moreover,we provide evidence that pre-S2 and S regions of HBenvAg contain the critical residues for the interaction with soluble Tf. Our data not only explain HBV entry into a variety of host activated cells, but may also help in developing strategies to alter the course of chronic HBV infection.
SOLUBLE TRANSFERRIN MEDIATES TARGETING OF HEPATITIS-B ENVELOPE ANTIGEN TO TRANSFERRIN RECEPTOR AND ITS PRESENTATION BY ACTIVATED T-CELLS / Maria Cristina, Gagliardi; Roberto, Nisini; Rosalba, Benvenuto; Guido De, Petrillo; M. L., Michel; Barnaba, Vincenzo. - In: EUROPEAN JOURNAL OF IMMUNOLOGY. - ISSN 0014-2980. - 24:6(1994), pp. 1372-1376. [10.1002/eji.1830240620]
SOLUBLE TRANSFERRIN MEDIATES TARGETING OF HEPATITIS-B ENVELOPE ANTIGEN TO TRANSFERRIN RECEPTOR AND ITS PRESENTATION BY ACTIVATED T-CELLS
BARNABA, Vincenzo
1994
Abstract
In a previous study, we identified that transferrin receptor (TfR) is the receptor utilized by hepatitis B virus (HBV) to enter T cells. We demonstrated that hepatitis B envelope antigen (H-BenvAg) is taken up by activated T cells via TfR, processed in endosomal compartments, and presented on class II molecules to specific CD4(+) T cell clones. Herein, we report that binding to soluble ferric Tf by HBenvAg is needed in TfR-mediated endocytosis. Accordingly, presentation of HBenvAg by activated T cells is not observed in serum-free medium and is restored by addition of soluble Tf. Moreover,we provide evidence that pre-S2 and S regions of HBenvAg contain the critical residues for the interaction with soluble Tf. Our data not only explain HBV entry into a variety of host activated cells, but may also help in developing strategies to alter the course of chronic HBV infection.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.