Peptide name : p776

Source/Organism : Synthetic Peptide

Linear/Cyclic : Linear

Chirality : L

Peptide length: 15

C-terminal modification: Linear

N-terminal modification : Free

Non-natural peptide information: None

Assay type : ELISPOT assay

Assay time : Not found

Activity : Not found

Cell line : Not found

Cancer type : Tumor

Other activity : Not found

Amino acid composition bar chart :

Molecular mass : 1533.8332 Dalton

Aliphatic index : 1.426

Instability index : 52.9867

Hydrophobicity (GRAVY) : 1.1067

Isoelectric point : 8.222

Charge (pH 7) : 0.7492

Aromaticity : 0.066

Molar extinction coefficient (cysteine, cystine): (1490, 1490)

Hydrophobic/hydrophilic ratio : 2.75

hydrophobic moment : -0.652

Missing amino acid : W,H,Q,T,M,E,K,F,D,N,A

Most occurring amino acid : G

Most occurring amino acid frequency : 3

Least occurring amino acid : P

Least occurring amino acid frequency : 1

Secondary structure fraction (Helix, Turn, Sheet): (0.2, 0.4, 0.4)

SMILES Notation: CC[C@H](C)[C@H](NC(=O)CNC(=O)[C@H](CC(C)C)NC(=O)[C@H](CC(C)C)NC(=O)[C@H](CCCNC(=N)N)NC(=O)[C@H](CO)NC(=O)[C@@H](NC(=O)[C@H](Cc1ccc(O)cc1)NC(=O)[C@@H]1CCCN1C(=O)[C@H](CO)NC(=O)CNC(=O)[C@@H](NC(=O)CN)C(C)C)C(C)C)C(=O)N[C@@H](CS)C(=O)N[C@@H](CC(C)C)C(=O)O

1 : Gritzapis AD, et al. Ontak reduces the immunosuppressive tumor environment and enhances successful therapeutic vaccination in HER-2/neu-tolerant mice. Cancer Immunol Immunother. 2012; 61:397-407. doi: 10.1007/s00262-011-1113-4

Paper title : Ontak reduces the immunosuppressive tumor environment and enhances successful therapeutic vaccination in HER-2/neu-tolerant mice.

Doi : https://doi.org/10.1007/s00262-011-1113-4

Abstract : Disrupting tumor-mediated mechanisms suppressing host immunity represents a novel approach to tumor immunotherapy. Depletion of regulatory T cells (Tregs) increases endogenous anti-tumor immunity and the efficacy of active immunotherapy in experimental tumor models. HLA-A2.1/HLA-DR1 (A2.1/DR1) × BALB- neuT+ (neuT+) triple transgenic mice represent an improvement over neuT+ mice for evaluating vaccination regimens to overcome tolerance against HER-2/neu. We questioned whether depletion of Tregs with Denileukin diftitox (Ontak) enhances the efficacy of a therapeutic vaccine consisting of HER-2(85-94) (p85) CTL and HER-2(776-790) (p776) Th peptides against the growth of TUBO.A2 transplantable tumor in male A2.1/DR1 × neuT+ Tg mice. While the therapeutic vaccine primed the tumor-reactive CD8+ CTLs and CD4+ effector T lymphocytes (Teffs) compartment, inducing activation, tumor infiltration, and tumor rejection or delay in tumor growth, treatment with Ontak 1 day prior to vaccination resulted in enhanced CD4+ and CD8+ T-cell-mediated vaccine-specific immune responses in the periphery. This was closely associated with greater infiltration and a striking change in the intratumor balance of Tregs and vaccine-specific CTLs/Teffs that directly correlated with markedly enhanced antitumor activity. The data suggest that Tregs control both CD4+ and CD8+ T-cell activity within the tumor, emphasize the importance of the intratumor ratio of vaccine-specific lymphocytes to Tregs, and demonstrate significant inversion of this ratio and correlation with tumor rejection during Ontak/vaccine immunotherapy.