Conformational changes in Sindbis virus E1 glycoprotein induced by monoclonal antibody binding

Area of Science:

• Virology
• Immunology
• Structural Biology

Background:

• Sindbis virus is an enveloped virus with surface glycoproteins E1 and PE2.
• Understanding the interactions between viral proteins and antibodies is crucial for developing antiviral strategies.

Purpose of the Study:

• To characterize the specificity and binding interactions of monoclonal antibodies against Sindbis virus E1 and PE2 proteins.
• To investigate the effect of antibody binding on the stability of E1-PE2 complexes.

Main Methods:

• Using monoclonal antibodies (30.2, 30.11, 30.12) against Sindbis virus-infected cells.
• Employing immunoprecipitation assays with non-ionic detergent and SDS.
• Conducting competition binding experiments with radiolabeled antibodies.

Main Results:

• Antibody 30.2 is specific for E1, while other antibodies (30.11, 30.12) also bind E1.
• Antibody binding can either precipitate E1-PE2 complexes or induce their dissociation.
• Antibodies bind to distinct antigenic sites on E1, with some interactions enhancing binding and altering conformation.

Conclusions:

• Monoclonal antibodies exhibit distinct binding patterns and effects on Sindbis virus E1-PE2 complex stability.
• Antibody-induced conformational changes in E1 influence its interaction with PE2 and other antibodies.
• These findings provide insights into Sindbis virus structural protein interactions and antibody recognition.