P3 peptide

P3 peptide

• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

Batch to batch variation of the purity

ALFDIESKV

Ala-Leu-Phe-Asp-Ile-Glu-Ser-Lys-Val

9

95.5%

C₄₇H₇₆N₁₀O₁₅

1021.18

Synthetic

Powder

P3 (ALFDIESKV) is a 9-mer HLA-A02:01-restricted CTL epitope originating from Prostate-Specific Membrane Antigen (PSMA, FOLH1; UniProt ID: Q04609), located at the 711–719 amino acid segment of the PSMA extracellular domain. With the highest predicted binding score (0.97) and a very low percentile rank (0.01) for HLA-A02:01 interaction, this peptide displays exceptional MHC class I binding capacity, confirmed by in vitro ELISA assays showing high-affinity binding at low concentrations (5 μM). It adopts a stable α-helical conformation in phosphate-buffered saline, and molecular docking analysis verifies its favorable accommodation within the HLA-A*02:01 binding cleft (binding energy −216.37). As the most functionally potent epitope candidate in preclinical evaluations, ALFDIESKV induces the strongest IFN-γ response (185 ± 12.3 SFUs per 10⁵ splenocytes) and the highest frequency of IFN-γ+ CD8+ T cells (7.4% ± 0.5%) in transgenic mice, alongside robust polyfunctional CD8+ T cell activation with TNF-α co-expression. The peptide also possesses high sequence conservation and efficient proteasomal cleavage potential, ensuring its physiological relevance for endogenous antigen presentation.

Normally, this peptide will be delivered in lyophilized form and should be stored in a freezer at or below -20 °C. For more details, please refer to the manual: Handling and Storage of Synthetic Peptides

• Yueting Huang, Yang Yang, Yanni Xie, Yue Shu, Siqi Yang, Xuezhi Long, Zhipeng Wen, Xiaolu Duan, Li Fu, Di Gu & Tuxiong Huang (2026) Preclinical Assessment of HLAA*02:01-Restricted PSMA and STEAP1 Epitopes for Peptide-Based Immunotherapy in Prostate Cancer, Drug Design, Development and Therapy, , 576346, DOI: 10.2147/DDDT.S576346

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.