LAG-1 Human, His

LAG-1 is a chemokine that signals through the CCR5 receptor. It is nearly identical to MIP-1β (Macrophage Inflammatory Protein-1β), with only two amino acid substitutions: arginine for histidine at position 22 and serine for glycine at position 47 of the mature protein . The recombinant form of LAG-1 is produced in E. coli and is a non-glycosylated polypeptide chain containing 94 amino acids, including a 25 amino acid His-tag at the N-terminus . The molecular mass of this recombinant protein is approximately 10.5 kDa .

LAG-1 exhibits several important biological activities:

• Chemoattraction: It attracts monocytes, a type of white blood cell, to sites of inflammation .
• HIV Suppression: LAG-1 has been shown to act as an HIV-suppressive factor, likely due to its interaction with the CCR5 receptor, which is also a co-receptor for HIV entry into cells .

Recombinant LAG-1 is widely used in research to study its role in immune responses and its potential therapeutic applications. Its ability to chemoattract CCR5-transfected cells is often utilized in functional assays . Additionally, its activity as an HIV-suppressive factor makes it a valuable tool in HIV research .

The recombinant form of LAG-1 is produced in E. coli and purified using proprietary chromatographic techniques to ensure high purity (≥ 98% by SDS-PAGE gel and HPLC analyses) . The endotoxin level is kept below 0.1 ng/µg of protein, making it suitable for various research applications .