respiratory syncytial virus LID delta M2-2

Respiratory syncytial virus LID ΔM2-2 is a live-attenuated vaccine candidate developed by the National Institute of Allergy and Infectious Diseases (NIAID) for the prevention of RSV infection, particularly in infants. The vaccine is based on a recombinant version of the RSV strain A2 (using the LID or 'Low-Immune-Determinant' backbone) that has been attenuated by the deletion of the M2-2 gene. The M2-2 protein normally functions as a structural switch that regulates the balance between viral RNA transcription and replication. Its deletion results in a unique phenotype characterized by significantly restricted viral RNA replication but significantly increased mRNA transcription. This leads to a high level of viral protein (antigen) expression, enhancing the vaccine's immunogenicity, while the restricted replication ensures the virus is sufficiently attenuated for safety. It is typically administered intranasally to induce both systemic and local mucosal immunity.

Other names

live-attenuated RSV LID delta M2-2 vaccinerecombinant RSV LID delta M2-2