Triple Point Biologics' Serine Proteinase Inhibitors recombinant catalog covers members of the serpin superfamily — including SERPINA1, SERPINB-class intracellular inhibitors, SERPINC1 (antithrombin), SERPINE1 (PAI-1), SERPING1 (C1-inhibitor), and SERPINH1 (HSP47) — produced as recombinant proteins in HEK293 expression systems. Serpins are a structurally conserved family of serine protease inhibitors characterized by a reactive center loop (RCL) that undergoes a metastable-to-stable conformational transition upon covalent complex formation with a target protease. Physiologically, individual family members regulate distinct but intersecting arms of protease biology: SERPINC1 is a principal inhibitor of thrombin and factor Xa in the coagulation cascade; SERPINE1 modulates fibrinolysis through inhibition of tissue- and urokinase-type plasminogen activators; SERPING1 controls early complement activation via inhibition of C1r and C1s; and SERPINH1 functions as a collagen-specific chaperone in the endoplasmic reticulum. These proteins have been extensively characterized in published studies of thrombotic disorders, angioedema, fibrosis, and inflammatory disease, making recombinant forms standard reference material in plasma protein and protease biology research.

All recombinant serpins in the Triple Point Biologics catalog are paired with a matched rabbit polyclonal antibody raised in the same laboratory, validated for Western blot and IHC against the same recombinant protein used as immunogen. This lot-to-lot correspondence between antigen and antibody — maintained across more than 30 years of proteinase inhibitor antibody production at Triple Point Biologics since 1994 — provides a traceable internal standard for detection experiments. Cross-reactivity to human orthologs is validated; reactivity to additional species is predicted based on sequence identity and noted per product.

Recombinant serpins from this collection are used as positive controls in protease activity assays, inhibition kinetics studies, surface plasmon resonance binding experiments, and ELISA standard curve generation. For guidance on incorporating recombinant proteins into functional inhibition workflows, see the Triple Point Biologics guide to protease activity assays. For best practices on using HEK293-expressed recombinant proteins as immunodetection controls, refer to the guide on recombinant protein positive controls.