Human lymphotactin (Lptn)/XCL1 (also named human SCM-1 alpha and ATAC) and its mouse homologue belong to the C or gamma subfamily of chemokines. The C chemokines lack two (the 1st and 3rd ) of the four invariant cysteine residues normally found in the CC and CXC chemokines and have an extended carboxy terminus. Human lymphotactin encodes a 114 amino acid residue precursor protein with a 21 amino acid residue predicted signal peptide. The expression of lymphotactin is abundant in some activated T cells such as activated CD8+ T cells and other class I MHC restricted T cells. Lptn expression is absent in CD4+ T cells. Human and mouse Lptn share approximately 60% amino acid sequence homology. The gene for lymphotactin has been mapped to chromosome 1 in both human and mouse. Recombinant human lymphotactin has been shown to have chemotactic activity for lymphocytes and NK cells. The orphan receptor GPR5 has been reported to be the specific receptor for Lptn. Product Properties Synonyms ATAC, C motif chemokine 1, Cytokine SCM-1, Lymphotaxin, SCM-1-alpha, Small-inducible cytokine C1, XC chemokine ligand 1 Accession P47992 GeneID 6375 Source E.coli-derived Human Lymphotactin/XCL1, Gly23-Gly114. Molecular Weight Approximately 10.2 kDa. AA Sequence GSEVSDKRTC VSLTTQRLPV SRIKTYTITE GSLRAVIFIT KRGLKVCADP QATWVRDVVR SMDRKSNTRN NMIQTKPTGT QQSTNTAVTL TG Tag None Physical Appearance Sterile Filtered White lyophilized (freeze-dried) powder. Purity > 98% by SDS-PAGE and HPLC analyses. Biological Activity The biological activity determined by a chemotaxis bioassay using human T-lymphocytes is in a concentration of 10-100 ng/mL. Fully biologically active when compared to standard. Endotoxin < 1.0 EU per 1μg of the protein by the LAL method. Formulation Lyophilized from a 0.2 μm filtered concentrated solution in 20 mM PB, pH 7.4, 150 mM NaCl. Reconstitution We recommend that this vial be briefly centrifuged prior to opening to bring the contents to the bottom. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1.0 mg/mL. Stock solutions should be apportioned into working aliquots and stored at ≤ -20°C. Further dilutions should be made in appropriate buffered solutions. Shipping and Storage The products are shipped with ice pack and can be stored at -20℃ to -80℃ for 1 year. Recommend to aliquot the protein into smaller quantities when first used and avoid repeated freeze-thaw cycles. Cautions 1. Avoid repeated freeze-thaw cycles. 2. For your safety and health, please wear lab coats and disposable gloves for operation. 3. For research use only!
