cemip2 Antibody

What is CEMIP2 and what are its alternative names in the scientific literature?

CEMIP2 (Cell migration inducing hyaluronidase 2) is a membrane-bound protein involved in hyaluronan metabolism. It is also known as cell surface hyaluronidase, transmembrane protein 2 (TMEM2), and TMEM2. In humans, the canonical protein has 1383 amino acid residues with a molecular mass of 154.4 kDa and is primarily localized in the cell membrane. Up to two different isoforms have been reported for this protein, and it is widely expressed across many tissue types. CEMIP2 belongs to the CEMIP protein family and is involved in angiogenesis. The protein undergoes post-translational modifications, notably glycosylation .

What is the molecular function of CEMIP2 in cellular processes?

Recent research indicates that human TMEM2 (CEMIP2) functions as a regulator of hyaluronan metabolism rather than as a direct catalytic hyaluronidase. It mediates the initial cleavage of extracellular high-molecular-weight hyaluronan into intermediate-size fragments of approximately 10-5 kDa. CEMIP2 shows high specificity for hyaluronan and cannot cleave other glycosaminoglycans such as chondroitin sulfate or dermatan sulfate. It plays essential roles in systemic hyaluronan catabolism and turnover, regulates cell adhesion and migration via hyaluronan degradation at focal adhesion sites, and acts as a regulator of angiogenesis and heart morphogenesis .

How do mouse and human CEMIP2 proteins compare structurally and functionally?

Mouse and human TMEM2 (CEMIP2) share similar protein structures with approximately 66% nucleotide homology and 87% amino acid sequence homology. Both proteins contain the G8 and GG domains and have three PbH1 repeats in the C-terminal extracellular domain (ECD). Research investigating chimeric constructs of human and mouse TMEM2 has shown that the GG domain of mouse TMEM2 is critical for its enzymatic activity. This structural conservation explains why antibodies developed against one species often cross-react with CEMIP2 from other species .

What are the common applications for CEMIP2 antibodies in research?

CEMIP2 antibodies are primarily used for immunodetection of the protein in various experimental contexts. The most common applications include:

These applications enable researchers to detect CEMIP2 expression, determine subcellular localization, and investigate its role in various biological processes .

How can researchers distinguish between CEMIP2's regulatory role versus direct enzymatic activity in hyaluronan metabolism?

To differentiate between CEMIP2's regulatory functions and direct enzymatic activity, researchers should implement multi-faceted experimental approaches:

• In vitro enzymatic assays: Compare purified CEMIP2 with known hyaluronidases using substrate degradation assays with purified hyaluronan. True enzymatic activity should show direct, concentration-dependent substrate degradation.

• Domain mutation studies: Create constructs with mutations in the GG domain, which is critical for enzymatic activity in mouse TMEM2. Comparing wild-type and mutant proteins can reveal whether the protein directly catalyzes reactions or regulates other enzymes.

• Protein-protein interaction studies: Use co-immunoprecipitation with CEMIP2 antibodies followed by mass spectrometry to identify binding partners involved in hyaluronan metabolism.

• Temporal gene expression analysis: Monitor expression patterns of CEMIP2 alongside other hyaluronidases (e.g., HYBID) after cytokine stimulation. Research shows that IL-1β and TGF-β induce CEMIP2 expression while suppressing HYBID expression, suggesting regulatory relationships .

What are the critical considerations when designing knockdown experiments targeting CEMIP2?

When designing CEMIP2 knockdown experiments, researchers should consider several critical factors:

• Downstream gene effects: CEMIP2 knockdown affects the expression of other hyaluronan-related genes. Research demonstrates that suppression of HYBID expression and enhancement of HAS2 expression by proinflammatory cytokines were canceled by CEMIP2 silencing .

• Temporal dynamics: Time-course experiments are essential as cytokine-induced changes in CEMIP2 expression have specific temporal patterns. IL-1β stimulation increases CEMIP2 mRNA expression significantly from 3 hours, reaching a plateau at 6 hours, while TGF-β induces a more gradual increase .

• Validation methods: Confirm knockdown efficiency at both mRNA (qRT-PCR) and protein levels (Western blot with CEMIP2 antibodies) to ensure robust silencing.

• Functional assays: Include hyaluronan degradation assays to determine whether CEMIP2 knockdown alters extracellular hyaluronan levels and composition.

• Cell type considerations: Different cell types may exhibit varying dependencies on CEMIP2 for hyaluronan metabolism, requiring cell type-specific optimization.

How should researchers approach epitope selection when choosing CEMIP2 antibodies for specific applications?

Epitope selection is critical for successful CEMIP2 antibody applications:

• Domain-specific epitopes: For structure-function studies, select antibodies targeting functional domains like the G8 or GG domains. Research has shown the GG domain is critical for enzymatic activity in mouse TMEM2 .

• Application-specific considerations:

  • For Western blot: Antibodies targeting linear epitopes (e.g., middle region antibodies) typically perform better as proteins are denatured .

  • For immunoprecipitation: Antibodies recognizing native conformations are preferred.

  • For immunohistochemistry: Consider epitope accessibility in fixed tissues; some commercial antibodies are validated specifically for paraffin-embedded samples .

• Cross-reactivity assessment: When studying CEMIP2 across species, evaluate whether the epitope is conserved in the target species. Given the 87% amino acid homology between mouse and human CEMIP2, many antibodies cross-react across species .

• Isoform discrimination: If studying specific CEMIP2 isoforms, select antibodies targeting regions present in one isoform but not others.

• Post-translational modifications: Consider whether the epitope contains sites for glycosylation or other modifications that might interfere with antibody binding.

What experimental approaches can elucidate CEMIP2's role in cell migration and adhesion?

To investigate CEMIP2's role in cell migration and adhesion, researchers should consider these experimental approaches:

• Wound healing assays: Combined with CEMIP2 knockdown or overexpression to assess effects on collective cell migration rates.

• Single-cell tracking: Time-lapse microscopy with fluorescently labeled cells to quantify migration parameters (velocity, directionality, persistence).

• Focal adhesion analysis: Immunofluorescence co-staining for CEMIP2 and focal adhesion markers (paxillin, vinculin) to assess correlation between CEMIP2 localization and adhesion dynamics.

• Hyaluronan-dependent migration: Compare migration on hyaluronan-rich versus hyaluronan-free substrates to determine specificity of CEMIP2's effects.

• 3D invasion assays: Using hyaluronan-rich matrices to better recapitulate physiological environments where CEMIP2 functions.

• Adhesion strength measurements: Employing techniques like atomic force microscopy or centrifugal adhesion assays to quantify CEMIP2's impact on cell-substrate binding forces.

Research has demonstrated that CEMIP2-mediated hyaluronan degradation plays a critical role in the adhesion and migration of cells on hyaluronan-rich extracellular matrix substrates .

How does cytokine regulation of CEMIP2 impact experimental design in inflammation studies?

Cytokine regulation of CEMIP2 introduces important considerations for inflammation research:

• Temporal dynamics: When NHDFs (Normal Human Dermal Fibroblasts) are stimulated with IL-1β (1 ng/ml), CEMIP2 mRNA expression increases significantly from 3 hours and reaches a plateau at 6 hours. TGF-β (1 ng/ml) induces CEMIP2 expression more gradually. Experimental timepoints should capture these dynamics .

• Concentration-response relationships: The effects of cytokines on CEMIP2 expression are dose-dependent. Experiments should include concentration titrations to determine optimal stimulation conditions.

• Reciprocal regulation: Cytokine-induced increases in CEMIP2 expression are inversely correlated with decreases in HYBID expression. This reciprocal relationship requires monitoring multiple genes simultaneously .

• Functional consequences: Changes in CEMIP2 and related gene expression correlate with altered extracellular hyaluronan levels. Hyaluronan quantification should accompany gene expression studies.

• Pathway analysis: Different cytokines may regulate CEMIP2 through distinct signaling pathways, necessitating pathway inhibitor studies to determine specific mechanisms.

What are the optimal sample preparation methods for detecting CEMIP2 in different applications?

Optimal sample preparation varies by application:

For Western Blot:

• Use lysis buffers containing detergents suitable for membrane proteins (e.g., RIPA buffer with 1% Triton X-100)

• Include protease inhibitor cocktails to prevent degradation

• Maintain samples at 4°C during processing

• For mouse heart tissue lysates (a validated positive control), mechanical homogenization followed by detergent extraction is recommended

• Load 20-40 μg of total protein per lane

For Immunohistochemistry:

• Formalin fixation followed by paraffin embedding preserves CEMIP2 antigenicity

• Perform heat-induced epitope retrieval using citrate buffer (pH 6.0)

• Human liver tissue, rat kidney tissue, and mouse kidney tissue serve as validated positive controls

• Use hematoxylin as a counterstain to provide cellular context

• Block endogenous peroxidase activity before antibody application

For Immunocytochemistry:

• Fix cells with 4% paraformaldehyde (10-15 minutes at room temperature)

• Permeabilize with 0.1-0.2% Triton X-100 (5-10 minutes)

• Block with 5% normal serum in PBS (1 hour at room temperature)

• Incubate with primary antibody overnight at 4°C

What controls should be included when using CEMIP2 antibodies for reliable interpretation?

Rigorous controls are essential for reliable results:

Positive Controls:

• Mouse heart tissue lysate for Western blot analysis

• Paraffin-embedded human liver tissue for IHC-P

• Paraffin-embedded rat and mouse kidney tissue for IHC-P

Negative Controls:

• Primary antibody omission control

• Isotype control (rabbit IgG at the same concentration)

• Peptide competition assay (pre-incubating antibody with immunizing peptide)

• CEMIP2 knockdown samples (siRNA-treated cells)

Specificity Controls:

• Compare staining patterns with antibodies targeting different CEMIP2 epitopes

• Verify molecular weight in Western blot (expected 154.4 kDa)

• Cross-validate results using multiple detection methods

How can researchers troubleshoot common issues with CEMIP2 antibody applications?

Common issues and troubleshooting strategies include:

Weak or No Signal:

• Increase antibody concentration (try 1:500 for Western blot if 1:1000 fails)

• Extend incubation time (overnight at 4°C)

• Optimize antigen retrieval for IHC (try different pH buffers and heating times)

• Verify that your sample expresses CEMIP2 (it is widely expressed but levels vary)

• Ensure epitope integrity is maintained during sample preparation

High Background:

• Increase blocking time or concentration (5% BSA in TBST for Western blot)

• Use more stringent washing (additional washes with 0.1% Tween-20)

• Decrease primary antibody concentration

• Ensure proper blocking of endogenous peroxidase/phosphatase

• Filter antibody solutions before use

Multiple Bands in Western Blot:

• Determine if bands represent isoforms (CEMIP2 has up to 2 reported isoforms)

• Check for partial degradation products (add additional protease inhibitors)

• Verify antibody specificity through knockdown experiments

• Use gradient gels for better resolution of high molecular weight proteins

• Consider protein glycosylation (CEMIP2 undergoes glycosylation which can affect migration)

What are the recommended storage and handling conditions for maximizing CEMIP2 antibody performance?

To maintain optimal antibody activity:

• Storage temperature: Store concentrated stocks at -20°C and working dilutions at 4°C for up to one week.

• Aliquoting: Divide antibody into small aliquots upon receipt to avoid repeated freeze-thaw cycles.

• Formulation: Commercial CEMIP2 antibodies are typically formulated in PBS (pH 7.4) with 0.2% BSA and 40% glycerol, with 0.05% sodium azide as a preservative .

• Thawing procedure: Thaw antibodies completely at 4°C before use; avoid rapid warming.

• Mixing method: Mix by gentle inversion rather than vortexing to prevent protein denaturation.

• Transportation: Transport on ice when moving between laboratories.

• Documentation: Maintain records of antibody lot numbers, dilutions, and experimental performance.

• Expiration: Most antibodies remain effective for at least 12 months when stored properly, but verify activity before critical experiments.

How can CEMIP2 antibodies be utilized to study its role in cancer biology?

CEMIP2 antibodies offer several approaches for investigating cancer:

• Expression profiling: Evaluate CEMIP2 expression across cancer types and stages using tissue microarrays. Commercial antibodies have been validated in various cancer cell lines including U2OS (osteosarcoma), BT474 (breast carcinoma), DU145 (prostate adenocarcinoma), and TRAMP-C2 (mouse adenocarcinoma) .

• Functional studies: Combine CEMIP2 antibody staining with markers of invasion, migration, or angiogenesis to correlate expression with functional outcomes.

• Hyaluronan metabolism: Many tumors have altered hyaluronan metabolism. Use CEMIP2 antibodies alongside hyaluronan staining to assess correlation with tumor hyaluronan content.

• Therapeutic targeting: Validate CEMIP2 as a potential therapeutic target by confirming protein expression in patient samples.

• Mechanistic investigations: Use CEMIP2 antibodies in co-immunoprecipitation experiments to identify cancer-specific protein interactions.

• Response biomarkers: Monitor changes in CEMIP2 expression after treatment with chemotherapy or targeted therapies.

What approaches can researchers use to study the relationship between CEMIP2 and HYBID in hyaluronan metabolism?

To investigate the CEMIP2-HYBID regulatory relationship:

• Co-expression analysis: Perform dual immunostaining or sequential Western blots to examine correlation between CEMIP2 and HYBID expression across tissues or cell lines.

• Cytokine stimulation: Research shows that proinflammatory cytokines (IL-1β, TGF-β) upregulate CEMIP2 while downregulating HYBID expression. Time-course experiments with both proteins can reveal regulatory dynamics .

• Knockdown studies: CEMIP2 silencing prevents cytokine-induced suppression of HYBID, suggesting regulatory control. Perform knockdown of each protein and monitor effects on the other's expression .

• Promoter analysis: Investigate whether CEMIP2 directly or indirectly regulates HYBID transcription through reporter assays or chromatin immunoprecipitation.

• Functional hyaluronan assays: Compare hyaluronan degradation patterns when manipulating CEMIP2, HYBID, or both to determine their relative contributions.

• Protein interaction studies: Use proximity ligation assays or co-immunoprecipitation to assess whether CEMIP2 and HYBID physically interact or exist in the same protein complexes.

How do CEMIP2 antibodies contribute to angiogenesis research?

CEMIP2 antibodies enable several approaches in angiogenesis research:

• Vascular expression profiling: Immunohistochemical analysis of CEMIP2 in developing and mature blood vessels using validated antibodies in tissues like liver and kidney, which show robust CEMIP2 expression .

• Co-localization studies: Combine CEMIP2 antibodies with endothelial markers (CD31, vWF) to assess expression in vascular structures.

• Mechanistic investigations: CEMIP2 acts as a regulator of angiogenesis by mediating degradation of extracellular hyaluronan, thereby influencing VEGF signaling. Antibodies can help track this regulatory relationship .

• In vitro models: Apply CEMIP2 antibodies in tube formation assays to correlate protein localization with functional endothelial behavior.

• Developmental studies: Given that CEMIP2 gene orthologs have been reported in zebrafish (where it was initially characterized), antibodies can be valuable for studying evolutionary conservation of angiogenic mechanisms .

• Therapeutic assessment: Evaluate CEMIP2 as a potential anti-angiogenic target through expression studies in pathological angiogenesis.