Recombinant Human C-C motif chemokine 3-like 1 protein (CCL3L1) (Active)

CCL3L1 is a potent CCR5 ligand whose copy-number variation has been linked to differential HIV-1 susceptibility, making precise functional studies of this chemokine critically important. This tag-free recombinant human CCL3L1 encompasses the full-length mature sequence (residues 24–93) and demonstrates robust biological activity in a human monocyte chemotaxis bioassay at 1.0–10 ng/mL, providing a suitable basis for migration assays, CCR5/CCR1 signaling pathway analyses involving MAPK and NF-κB activation, and in vivo inflammation models. Endotoxin levels below 1.0 EU/μg minimize LPS-driven artifacts that can confound monocyte and macrophage functional readouts, while >97% purity by SDS-PAGE supports use as a reliable reference standard in cytokine detection assays or as a positive control for antibody validation by ELISA and western blot. The E. coli-expressed protein aligns with standards expected in cell-based activation and differentiation experiments where attribution of response to the target chemokine is essential.