SL9, HIV-1 p17 (77-85) peptide

• COA/MS/HPLC Report
• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

Batch to batch variation of the purity

The SL9 peptide, also known as HIV-1 p17 Gag_77–85 (SLYNTVATL), is an HLA-A*0201-restricted cytotoxic T lymphocyte (CTL) epitope. This epitope is derived from the HIV-1 Gag protein and has been extensively characterized. Studies indicate that SL9-specific CTLs can be primed ex vivo from naive CD8⁺ T cells of healthy donors using immature dendritic cells as antigen-presenting cells. These CTLs exhibit a helper-independent phenotype, capable of sustained clonal expansion and differentiation without CD4⁺ T cell help or exogenous interleukin-2, due to autocrine cytokine production.

The SL9-specific CTL response demonstrates a broad T cell receptor repertoire and functional avidity comparable to CTLs derived from infected individuals. These cells recognize not only the native SL9 epitope but also several naturally occurring variant peptides. However, SL9-CTLs display a unique sensitivity to paracrine interleukin-2, which can induce apoptosis. This immunogenic epitope is efficiently processed and presented, but its distinctive priming requirements and cytokine sensitivity contribute to its unusual manifestation over the course of infection.

• Kan-Mitchell J, Bisikirska B, Wong-Staal F, Schaubert KL, Bajcz M, Bereta M. The HIV-1 HLA-A2-SLYNTVATL is a help-independent CTL epitope. J Immunol. 2004 May 1;172(9):5249-61. doi: 10.4049/jimmunol.172.9.5249. PMID: 15100263.

Trifluoroacetic acid (TFA) is a common counterion from the purification process using High-Performance Liquid Chromatography (HPLC). The presence of TFA can affect the peptide's net weight, appearance, and solubility.

Impact on Net Weight: The TFA salt contributes to the total mass of the product. In most cases, the peptide content constitutes >80% of the total weight, with TFA accounting for the remainder.

Solubility: TFA salts generally enhance the solubility of peptides in aqueous solutions.

In Biological Assays: For most standard in vitro assays, the residual TFA levels do not cause interference. However, for highly sensitive cellular or biochemical studies, please be aware of its presence.