Recombinant Human Beta-defensin 4A protein (DEFB4A) (Active)

Human beta-defensin 2 (DEFB4A) plays a central role in epithelial innate immunity, recruiting immature dendritic cells while exerting direct bactericidal and fungicidal activity against invading pathogens. This tag-free recombinant form, encompassing the full-length mature protein (aa 24–64) expressed in *E. coli*, demonstrates confirmed chemotactic activity on immature human dendritic cells at 10–100 ng/ml, validating its biological functionality for innate immunity and host defense research. The endotoxin level of less than 1.0 EU/μg provides the stringent LPS control essential for MIC determination assays, bactericidal and fungicidal activity testing, and membrane disruption mechanistic studies where even trace endotoxin would confound antimicrobial readouts. Purity exceeding 98% by SDS-PAGE, combined with this low endotoxin burden, satisfies the quality criteria typical for drug resistance studies and quantitative dose-response experiments requiring precise peptide concentrations.