The present invention provides for a vector and a gene expression system for producing a soluble pentameric protein complex comprising the HCMV glycoproteins UL128, UL130, UL131, gH and gL or sequence variants thereof, as well as vaccine compositions comprising the same. The present invention further provides for a vaccine composition for use in prophylactically or therapeutically vaccinating against HCMV infections. Also disclosed are methods of producing the inventive vaccine. Furthermore, the present invention pertains to methods of vaccination of humans with the inventive vaccine composition.
