Disclosed are chimeric polypeptides based on viral membrane fusion proteins. More particularly, the present invention discloses chimeric polypeptides that comprise a virion surface exposed portion of a viral fusion protein and a heterologous structure-stabilizing moiety, and to complexes of those chimeric polypeptides. The present invention also discloses the use of these complexes in compositions and methods for eliciting an immune response to a fusion protein of an enveloped virus, or complex of the fusion protein, and/or for treating or preventing an enveloped virus infection. The present invention further discloses the use of the heterologous structure-stabilizing moiety for oligomerizing heterologous molecules of interest.
