Coxsackie B viruses use multiple receptors to infect human cardiac cells

Area of Science:

• Cardiology
• Virology
• Molecular Biology

Background:

• Viral myocarditis is a severe heart muscle inflammation, often fatal, primarily caused by human enteroviruses like Coxsackievirus B3 and B5.
• Understanding viral entry mechanisms into cardiac cells is crucial for developing effective treatments.

Purpose of the Study:

• To investigate the role of known receptors (Coxsackievirus adenovirus receptor protein - CAR and CD55) in Coxsackievirus B3 and B5 infection of cardiac cells.
• To identify potential new receptors used by these viruses for cardiac muscle entry.

Main Methods:

• Cardiac cells were treated with antibodies specific to CAR and CD55 to inhibit viral binding.
• Viral infectivity and binding assays were performed to assess the efficacy of antibody-mediated inhibition.
• Proteomic analysis was employed to identify novel viral binding proteins.

Main Results:

• Antibodies against CAR and CD55 did not completely inhibit Coxsackievirus B3 and B5 binding or infectivity in cardiac cells.
• Five novel proteins involved in Coxsackievirus binding to cardiac tissue were identified.
• These newly identified proteins are distinct from CAR and CD55.

Conclusions:

• The findings suggest that Coxsackievirus B3 and B5 may utilize a broader range of receptors than previously known for cardiac muscle infection.
• Existing therapeutic strategies targeting CAR and CD55 may be insufficient to fully prevent viral myocarditis.
• Further research into these novel receptors is warranted to understand their role in viral pathogenesis and develop targeted therapies.