Respiratory syncytial virus (RSV), also known as human orthopneumovirus, is an enveloped respiratory virus belonging to the family Pneumoviridae. RSV is a major cause of respiratory tract infections in infants and young children and can also cause significant disease in older adults and immunocompromised individuals. Infection may range from mild upper respiratory illness to bronchiolitis and pneumonia.
The RSV genome consists of approximately 15.2 kb of non-segmented, negative-sense, single-stranded RNA. It contains 10 genes arranged in the order NS1-NS2-N-P-M-SH-G-F-M2-L and encodes 11 proteins, as the M2 gene produces two distinct proteins, M2-1 and M2-2. These viral proteins coordinate genome replication, transcription, particle assembly, host immune modulation, and viral entry.
The attachment glycoprotein G and fusion glycoprotein F are the principal surface proteins involved in RSV entry. The G protein contributes to attachment to target cells, while the F protein mediates fusion of the viral and cellular membranes. The F protein exists in structurally distinct prefusion and postfusion conformations, with the prefusion form displaying several highly potent neutralizing antibody epitopes and serving as an important target for vaccine and therapeutic antibody development.
RSV is divided into antigenic groups A and B, which circulate concurrently and exhibit substantial genetic diversity, particularly in the G protein. RSV recombinant proteins, antibodies, pseudoviruses, and related assay reagents are valuable tools for studying viral entry, antigenicity, immune responses, neutralizing antibodies, vaccine candidates, antiviral agents, and diagnostic assay development.