Recombinant RSV Prefusion (DS-Cav1), Trimer

Respiratory syncytial virus (RSV) is a major cause of acute lower respiratory tract infection and hospitalization in infants¹. RSV F protein is a type I integral membrane protein essential for viral membrane fusion that is highly conserved among isolates of RSV A and B subgroups and is the primary target for RSV antiviral drug development². RSV F protein is synthesized as a 574 amino acid inactive precursor, assembled into a trimer, post-translationally modified, and then cleaved during activation for membrane fusion to produce F1, F2, and intervening peptide pep27². When functional F protein trimer in the virion membrane is triggered, F protein merges virus and host-cell membranes using the difference in folding energy between its pre-fusion (pre-F) and post-fusion (post-F) forms³. During infection, RSV-neutralizing antibodies target epitopes that reside primarily on the pre-F conformation^{3, 4}, particularly antigenic site Ø on the apex of pre-F, which is highly sensitive to neutralization and exclusive to the pre-F conformation⁵.

DS-Cav1 was developed as a variant F protein for vaccine use³. DS-Cav1 is a soluble pre-F trimeric subunit protein that is stabilized in the pre-F conformation via structurally supportive mutations^{3, 6}. Additionally, DS-Cav1 is engineered to stably expose antigenic site Ø on the trimer apex and present a “supersite” of overlapping epitopes that is highly sensitive to neutralization and can be recognized by multiple antibodies^{3, 6}. Immunization studies have shown DS-Cav1 vaccination elicits antibody responses to pre-F–exclusive surfaces on the apex as well as shared pre-F and post-F surfaces on the side of pre-F⁵. Additionally, the average neutralizing potency of F-specific antibodies increases with DS-Cav1 immunization.

Recombinant DS-Cav1 is provided under an intellectual property license from the National Institutes of Health (NIH). Leinco is licensed under NIH Patent No.:US 11,878,998B2 to manufacture and sell this product. The purchase of this protein conveys to the buyer the non-transferable right to use the purchased protein for research use only (RUO). As this protein is protected by the intellectual property rights of the NIH, the buyer of this protein (academic or commercial) is expressly prohibited from using the protein or any derivative in any commercial (revenue generating) activity. Such activities may include, but are not limited to, manufacturing, services, therapeutics, diagnostics, prophylactics or resale (including RUO).

Viral

P03420

Lyophilized

~180k Non-reducing conditions

60.5k monomer 181.5k Trimer

Lyophilized from PBS + 5% Trehalose

Reconstitute at 0.1-1 mg/ml using filtered deionized water. Gently mix by vortexing and/or inversion until fully dissolved. Centrifuge if necessary.

This lyophilized protein is stable for twelve months when stored at -20°C to -70°C. After aseptic reconstitution, this protein may be stored for one month at 2°C to 8°C or for three months at -20°C to -70°C in a manual defrost freezer. Avoid Repeated Freeze Thaw Cycles.

Ambient

Viral

Research Use Only

P03420

1. Hammitt LL, Dagan R, Yuan Y, et al. N Engl J Med. 386(9):837-846. 2022.
2. McLellan JS, Ray WC, Peeples ME. Curr Top Microbiol Immunol. 372:383-104. 2013.
3. McLellan JS, Chen M, Joyce MG, et al. Science. 342(6158):592-598. 2013.
4. Magro M, Mas V, Chappell K, et al. Proc Natl Acad Sci U S A. 109(8):3089-3094. 2012.
5. Crank MC, Ruckwardt TJ, Chen M, et al. Science. 365(6452):505-509. 2019.
6. Ruckwardt TJ, Morabito KM, Phung E, et al. Lancet Respir Med. 9(10):1111-1120. 2021.
7. Espeseth AS, Cejas PJ, Citron MP, et al. NPJ Vaccines. 5(1):16. 2020.
8. Chang LA, Phung E, Crank MC, et al. Sci Transl Med. 14(676):eade0424. 2022.
9. Steff AM, Monroe J, Friedrich K, et al. Nat Commun. 8(1):1085. 2017.