PMX53

A cell-permeable, orally available, and metabolically stable macrocyclic hexapeptidomimetic compound that acts as a non-competitive antagonist of complement C5a receptor (C5aR; CD88; IC₅₀ = 240 nM) and as a low-affinity agonist for MrgX2, a GPCR, in human mast cells Shown to specifically bind to C5aR1 and not to CaR2 and C3aR. Displays a broad range of anti-inflammatory effects, both in vitro and in vivo. Shown to inhibit C5a-induced neutrophil myeloperoxidase release (IC₅₀ = 22 nM) and chemotaxis (IC₅₀ = 75 nM). Preincubation with PMX-53 (~10 nM) blocks C5a-induced Ca2+ responses in HMC-1 and RBL-2H3 cells, but does not affect C3a responses. Suppresses the growth of 4T1 mammary carcinoma tumor xenograft in mice (1 mg/kg/every 2-3 days, s.c.). Reported to diminish C5a-mediated increase in pluripotency in human embryonic stem cells in the absence of FGF2.

Cell permeable: yes

Primary Target
C5aR

Reversible: yes

Packaged under inert gas

Toxicity: Standard Handling (A)

Ac-Phe-[Orn-Pro-dCha-Trp-Arg]

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

Lillegard, K., et al. 2014. JPET.351,344.
Vadrevu, S. K., et al. 2014. Cancer Res.74, 3454.
Liang, S., et al. 2011. J. Immun.186, 869.
Woodruff, T., et al. 2005. JPET.314, 811.

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