Cyclophilin B Human
Description
Enzymatic Activity
CypB catalyzes peptidyl-prolyl cis-trans isomerization, facilitating protein folding. This activity is inhibited by cyclosporin A (CsA), forming a complex critical for CsA-mediated immunosuppression .
Signaling and Binding Partners
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CD147 interaction: Binds to CD147 (Basigin) to regulate MAPK signaling, calcium transport, and apoptosis .
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Immune modulation: Mediates T-cell adhesion via β1 integrin activation and chemotaxis in macrophages .
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Pathogen interactions: Serves as a receptor for Plasmodium falciparum merozoites during erythrocyte invasion by binding PfRhopH3 ( M) .
Inflammatory Regulation
CypB attenuates TNF-α, IL-1β, and chemokine production in LPS-stimulated macrophages via Bcl-3 induction, contrasting with its proinflammatory roles in rheumatoid arthritis and sepsis .
Inflammatory Diseases
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Elevated in rheumatoid arthritis synovial fluid and coronary artery disease (CAD) T-cells .
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Enhances neutrophil chemotaxis and platelet adhesion to collagen .
Cancer
Overexpressed in breast, liver, colon, and pancreatic cancers, where it promotes tumor progression and metastasis .
Infectious Diseases
Facilitates P. falciparum invasion by forming a multi-protein complex with Basigin on erythrocytes .
Mechanistic Insights
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Cyclosporin A targeting: CypB mediates CsA uptake in T-cells via surface receptor binding, enhancing immunosuppressive activity .
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Anti-inflammatory effects: Pretreatment with CypB reduces LPS-induced TNF-α production by 70% in macrophages .
Therapeutic Applications
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Recombinant CypB (21.2 kDa, ENZ-313) is used to study isomerase activity ( nmol/min/mg) .
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Antibodies targeting CypB (e.g., D1V5J Rabbit mAb) enable detection in Western blotting .
Key Research Findings
Product Specs
Product Science Overview
Cyclophilin-B is a cyclosporine-binding protein that plays a crucial role in protein folding and trafficking within the ER. It is involved in the secretory pathway and is released in biological fluids . This protein can bind to cells derived from T- and B-lymphocytes and may regulate cyclosporine A-mediated immunosuppression .
Cyclophilin-B has been shown to interact with various cellular components, including the Gag protein, and is involved in p300-mediated degradation of CHOP in tumor cell adaptation to hypoxia . It also possesses proinflammatory properties and plays a principal role in ER redox homeostasis . High levels of Cyclophilin-B are found in inflammatory processes such as sepsis and rheumatoid arthritis .
Cyclophilin-B is identified as a candidate gene for Osteogenesis Imperfecta (OI-IX), an inherited disorder of connective tissue . Mutations in the PPIB gene, which encodes Cyclophilin-B, can lead to defects in collagen production, resulting in brittle bones and other connective tissue abnormalities .
