Development of an alternative neutralization assay using Akabane virus-based transcription and replication-competent virus-like particles.

Akabane virus (AKAV) and other orthobunyaviruses are associated with congenital abnormalities in domestic ruminants. The emergence of novel orthobunyaviruses poses a constant threat to animal health and the livestock industry. The neutralization assay represents a reliable test for detecting orthobunyavirus infections, but it requires virus isolation. Because of difficulties in virus isolation, the neutralization assay cannot be performed for some viruses associated with clinical cases. In this study, we generated AKAV-based transcription and replication-competent virus-like particles (trVLPs) bearing AKAV and Shamonda virus glycoproteins and performed an alternative neutralization assay using trVLPs. The results illustrated that trVLPs could be used to detect neutralizing antibodies in a similar manner as conventional neutralization assays using intact viruses. This alternative neutralization assay could be a powerful tool for detecting neutralizing antibodies against orthobunyaviruses, thereby overcoming the limitations of current diagnostic tests.