BD 4 Rat

Defensins are classified into two main subfamilies: alpha-defensins and beta-defensins. The primary distinction between these subfamilies lies in the pairing of their three disulfide bonds . BD-4 belongs to the beta-defensin subfamily, which is characterized by a six-cysteine motif that forms three intra-molecular disulfide bonds .

BD-4 is expressed in various tissues and organs in rats, including the testis, stomach, uterus, neutrophils, thyroid, lung, and kidney . This widespread expression suggests that BD-4 plays a significant role in protecting multiple organ systems from microbial infections.

BD-4 exhibits a broad spectrum of antimicrobial activity. It is expressed as the C-terminal portion of precursor proteins and is released by proteolytic cleavage of a signal sequence . The peptide ranges in size from 33 to 47 amino acid residues and has a molecular weight of approximately 4.4 kDa . BD-4 is fully biologically active and has been shown to be effective in chemotaxis bioassays using human monocytes at concentrations ranging from 0.1 to 100.0 ng/ml .

Recombinant BD-4 is typically produced in E. coli expression systems. The protein is then purified using proprietary chromatographic techniques to achieve a purity level of over 95% as analyzed by SDS-PAGE and HPLC . The endotoxin level is kept below 1 EU/μg of protein by the LAL method .

Upon receiving, BD-4 remains stable for up to six months when stored at -70°C or -20°C. Once reconstituted, the product should be stable for up to one week at 4°C or up to three months at -20°C. It is important to avoid repeated freeze-thaw cycles to maintain the protein’s stability and activity .

BD-4 is primarily used for laboratory research purposes. It is not intended for direct human use, including oral intake, injection, or clinical applications . Researchers utilize BD-4 to study its antimicrobial properties, its role in the immune system, and its potential therapeutic applications.