A 14-aa internally disulfide-bonded peptide that potently competes against SDF-1α/CXCL12 for CXCR4 binding (IC₅₀ = 0.91 nM; [SDF-1] = 100 nM) and protects MT-4 cells against X4-HIV strain HIV-1_IIIB infection (EC₅₀ = 4 nM in 5 d; MOI = 0.01) with no significant cytotoxicity (CC₅₀ = 56 µM; 5 d). Inhibits SDF-1-induced Ca²⁺ mobilization (IC₅₀ = 4.5 nM; [SDF-1] = 30 nM; CXCR4-expressing CHO cells) in vitro and effectively prevents CXCR4-dependent 5BC-5 metastasis in NK-depleted SCID mice in vivo (10 mg/kg i.p.) in vivo.

Please note that the molecular weight for this compound is batch-specific due to variable water content. Please refer to the vial label or the certificate of analysis for the batch-specific molecular weight. The molecular weight provided represents the baseline molecular weight without water.

Cell permeable: yes

Primary Target
CXCR4

Supplied as a trifluoroacetate salt.

Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 3 months at -20°C.

N^α-4-fluorobenzoyl-Arg-Arg-Nal-Cys⁴-Tyr-Cit-Lys-D-Lys-Pro-Tyr-Arg-Cit-Cys¹³-Arg-NH₂ (Disulfide bond: 4 → 13; Nal = L-3-(2-naphthyl)alanine; Cit = L-citrulline)

Otani, Y., et al. 2012. FEBS Lett.586, 3639.
Oishi, S., and Fujii, N. 2012. Org. Biomol. Chem.10, 5720.
Tamamura, H., et al. 2003. Org. Biomol. Chem.1 3663.
Tamamura, H., et al. 2003. Org. Biomol. Chem.1, 3656.

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany

Toxicity: Standard Handling (A)