B7-33 is an engineered single-chain peptide analogue derived from the B-chain of human H2 relaxin. Native H2 relaxin is a complex two-chain hormone containing multiple disulfide bonds, which brings high barriers for chemical synthesis and stability maintenance. B7-33 was specially optimized to abandon the complicated double-chain framework, while preserving the core pharmacophore capable of binding to RXFP1 receptor, greatly lowering the technical threshold of lab research.

It acts as a biased RXFP1 agonist with unique signaling selectivity. Different from native relaxin that triggers both cAMP and ERK1/2 cascades, B7-33 preferentially activates ERK1/2 and MMP2 related pathways. It can modulate extracellular matrix metabolism, promote collagen degradation and restrain excessive fibroblast deposition, making it a valuable research tool for organ fibrosis studies. Preclinical experiments explore its effects on cardiac, pulmonary and renal fibrosis, together with vascular tissue remodeling and cardioprotective mechanisms.

Our B7-33 is manufactured via solid-phase peptide synthesis with strict coupling and cleavage control. As a long linear peptide, it is prone to incomplete coupling and sequence deletion during synthesis. Each batch undergoes mass spectrometry validation to confirm full amino acid sequence, and HPLC chromatogram is applied to monitor impurity levels. The lyophilized form stabilizes the peptide structure and protects bioactivity during transportation and long-term frozen preservation.

When handling B7-33 in lab work, attention should be paid to its relatively short half-life in liquid state after reconstitution. Once dissolved, the peptide solution is sensitive to temperature rise and proteolytic degradation. It is strongly recommended to aliquot the reconstituted solution into small single-use portions and freeze immediately. Repeated thawing and prolonged exposure at room temperature will reduce biological activity. Standard laboratory protective equipment should be worn during weighing and sample preparation.