Disclosed are methods of treatment of a subject, such as a method of vaccination, immunomodulation or gene therapy of a subject. These methods comprise administering to the subject a modified enveloped viral particle, wherein the modified enveloped viral particle has been obtained by a method comprising the steps of a) incubating a fluid containing enveloped viral particles with one or more reactants consisting of a hydrophilic target domain and a lipophilic membrane anchor domain, wherein the lipophilic membrane anchor domain becomes integrated into the lipid double layer of the envelope of the viral particle, wherein the hydrophilic target domain becomes exposed to the fluid； and b) separating enveloped modified viral particles from excessive reactants.
