cpx-1 Antibody
Description
Introduction to CPX-1 Antibody
CPX-1 (Carboxypeptidase X-1), also referred to as CPXM1, is a member of the M14 metallocarboxypeptidase family. Despite structural similarities to enzymatically active carboxypeptidases, CPX-1 lacks catalytic activity due to missing critical residues required for zinc coordination . It is characterized by a discoidin domain (DSD) implicated in collagen binding and a carboxypeptidase-like domain . CPX-1 antibodies are specialized reagents designed to detect and study this protein in biological systems, enabling research into its roles in extracellular matrix interactions and potential disease associations .
Western Blot Performance
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Thermo Fisher’s PA5-31386: Detects CPX-1 at ~70 kDa in human cell lines (e.g., IMR32), consistent with its glycosylated form .
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Proteintech’s PTGS1 Antibody: Validated in HeLa, C2C12, and A431 cells, showing bands at 60–72 kDa .
Immunohistochemistry (IHC)
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PA5-31386: Localizes CPX-1 to cytoplasmic vesicles and extracellular matrices in human tissues .
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R&D Systems’ BAF2919: Optimized for neutralization assays, confirming specificity via blocking experiments .
Collagen-Binding Studies
CPX-1 antibodies have been critical in demonstrating that:
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CPX-1 binds collagen via its DSD domain, with R192A mutation reducing binding by 60% .
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Secreted CPX-1 exists as monomers and dimers; only monomers bind collagen under non-reducing conditions .
Role in Extracellular Matrix Interactions
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Collagen Binding: CPX-1’s discoidin domain facilitates collagen interaction, validated via pull-down assays using anti-CPX-1 antibodies .
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Secretion Mechanism: N-glycosylation is essential for CPX-1 secretion, as shown by tunicamycin inhibition studies .
Disease Associations
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Cancer: CPX-1 is overexpressed in colorectal cancer (CRC), with antibodies used to study its role in ROS-mediated apoptosis and autophagy .
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Neurological Disorders: CPX-1 antibodies aid in exploring its link to mirror movement disorders and nephrotic syndrome .
Table 2: Recommended Protocols
| Application | Dilution Range | Buffer Conditions | Key Controls |
|---|---|---|---|
| Western Blot | 1:500–1:2000 | PBS with 0.1% BSA | Knockout cell lysates |
| Immunohistochemistry | 1:500–1:2000 | Antigen retrieval (pH 9.0 TE buffer) | Isotype-matched IgG |
| ELISA | 0.2–1.0 µg/mL | Blocking with 5% non-fat milk | Recombinant CPX-1 protein |
Challenges and Future Directions
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- Research suggests that the primary function of complexin is to maintain the docked state of synaptic vesicles, both by inhibiting fusion and promoting priming. PMID: 21215631
- These observations indicate a dual role for CPX-1: suppressing synaptic vesicle (SV) exocytosis under low levels of endogenous neural activity, while simultaneously promoting synchronous fusion of SVs driven by a depolarizing stimulus. PMID: 21215634
Q&A
Based on the provided research materials and analysis of current antibody research trends, here is a professionally organized FAQ collection addressing scientific inquiries about CPX-1 antibody research:
Advanced Research Challenges
How to resolve contradictory data on antibody-dependent cellular cytotoxicity (ADCC) measurements?
Three validation approaches:
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Standardized neutralization assays (TZM-bl cells with HIV-1 pseudovirus)
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Multiparametric flow cytometry (CD107a degranulation + IFN-γ secretion)
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Computational modeling of FcγRIIIa binding kinetics (KD values <10 nM indicate clinical relevance)
How to validate antibody specificity in multiplex assays?
| Method | Resolution | Throughput |
|---|---|---|
| Epitope binning (BLI) | 0.1 nm | 96-well/run |
| Hydrogen-deuterium exchange MS | 5-10 residue | 48 samples/week |
| Cryo-EM structure mapping | 3-4 Å | 2 structures/month |
Critical controls: Include isotype-matched antibodies and target knockout cell lines in all functional assays.
Data Interpretation Framework
6. Analyzing discordant neutralization vs. clinical protection data:
Create protection thresholds using AMP trial parameters :
Where PE >60% requires:
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Serum neutralization ID₅₀ >1:500
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ADCC activity >20% specific lysis at 1 μg/mL
Statistical power: 90% detection requires N=1,500 participants across 3 geographic cohorts .
