Desmin mutations in cardiomyocytes increase susceptibility to coxsackievirus B3 infection by impairing antiviral IFN-β response and upregulating viral receptors expression

Desmin-related cardiomyopathies caused by mutations in the DES gene are characterized by cytoskeletal disorganization and impaired cardiomyocyte function. Viral infections, particularly with Coxsackievirus B3 (CVB3), have been implicated as environmental triggers for cardiac decompensation. However, the interaction between desmin mutations and viral infection has never been explored. Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) from a healthy donor (control-CMs) and from patients carrying DES S46Y , DES D214−E245del , or DES P419H mutations ( DES mut -CMs) were infected with the cardiovirulent enterovirus CVB3/28. Structural changes were assessed by immunofluorescence for sarcomeric proteins and desmin. Contractile function was evaluated through video-based motion tracking. Viral replication, protein expression and antiviral responses were measured via plaque assays, immunostaining, and qPCR. Coxsackievirus and Adenovirus Receptor (CAR) and cell-surface vimentin expression were quantified post-infection. DES mut -CMs exhibited baseline sarcomeric disorganization and desmin aggregation, which were further aggravated by CVB3/28 infection in a mutation-specific manner. CVB3/28 significantly reduced spontaneous contractility in control-CMs, DES S46Y , and DES P419H -CMs, with minimal effect in DES D214−E245del -CMs. Infected DES mut -CMs showed enhanced viral replication, increased VP1 expression and elevated virion release. This was accompanied by a stunted IFN-β response, reduced APOBEC3A expression, and infection-induced upregulation of viral receptors CAR and cell-surface vimentin. CVB3/28 infection compromises the structural integrity and contractile function of cardiomyocytes and exerts a more severe effect in cells harboring DES mutations. These findings underscore a pathogenic synergy between genetic cytoskeletal defects and viral infection, revealing a mechanistic basis for the heightened vulnerability of patients carrying mutation in DES gene to virus-induced cardiac decompensation. CVB3/28 infection disrupts cardiomyocyte structure and impairs contractility, with more severe effects in cells carrying DES mutations. By enhancing viral replication and weakening antiviral defenses, DES mutations act synergistically with CVB3/28 infection to increase the risk of cardiac dysfunction.