Target Specificity:
The PLAC8.1 Antibody targets the PLAC8 protein, a 112-amino-acid cysteine-rich molecule. While the term "PLAC8.1" is not explicitly defined in the provided sources, it likely refers to a specific isoform or variant of PLAC8. The antibody is raised in rabbit (polyclonal) and purified via immunogen affinity chromatography .
Conjugation:
The HRP (horseradish peroxidase) conjugation enables enzymatic detection in assays, with applications optimized for ELISA, immunohistochemistry (IHC), and Western blotting .
Purity and Validation:
Purity exceeds 95% as determined by SDS-PAGE . Specificity is validated through immunoblotting and immunofluorescence assays .
The HRP-conjugated antibody is commonly used to detect PLAC8 expression in lysates or supernatants . For example, in studies of duck hepatitis A virus (DHAV-1), Western blotting with this antibody revealed PLAC8 upregulation post-infection .
In zebrafish embryogenesis, PLAC8.1 antibodies (polyclonal rabbit) were used to visualize protein localization during gastrulation, showing cytosolic-to-membranous redistribution .
In pancreatic ductal adenocarcinoma (PDA) models, PLAC8 antibodies demonstrated its role in autophagosome-lysosome fusion, critical for tumor growth .
PLAC8.1 antibody with HRP conjugation is primarily utilized in ELISA, Western blotting, and immunohistochemistry applications. For ELISA applications, HRP-conjugated antibodies eliminate the need for secondary antibodies, providing direct detection capabilities with enhanced sensitivity and reduced background . The conjugation allows for one-step detection protocols, particularly valuable in multi-parameter analyses.
When using this antibody for Western blotting, optimal dilutions typically range from 1:1000 to 1:5000 depending on protein expression levels. For immunohistochemistry, antigen retrieval methods significantly impact staining quality, with citrate buffer (pH 6.0) generally yielding superior results for PLAC8 detection.
PLAC8.1 antibodies demonstrate variable cross-reactivity across species, with most commercial antibodies showing reactivity to human, mouse, and rat PLAC8 . Cross-reactivity verification is essential before initiating multi-species experiments. When designing experiments:
Confirm specific reactivity through manufacturer validation data
Run preliminary tests with positive control samples from each species
Adjust antibody concentrations for optimal signal-to-noise ratios in different species
Consider sequence homology between species (human PLAC8 shares approximately 73% homology with mouse orthologs)
Species-specific validation prevents misinterpretation of negative results that might stem from lack of cross-reactivity rather than absence of target protein.
HRP-conjugated antibodies require specific storage conditions to maintain enzymatic activity. For PLAC8.1 HRP-conjugated antibodies:
Store at 2-8°C for short-term (2-4 weeks) and -20°C for long-term storage
Avoid repeated freeze-thaw cycles (limit to 3-5 maximum)
Add glycerol (50%) when freezing to prevent ice crystal formation
Store in small aliquots to minimize freeze-thaw degradation
Protect from light exposure, particularly important for HRP conjugates
Activity degradation can be monitored through regular testing against control samples. Typical shelf-life for properly stored HRP-conjugated antibodies is 12-18 months, though enzymatic activity gradually decreases over time even under optimal conditions .
For detecting low PLAC8 expression levels, several advanced optimization strategies can be employed:
Signal amplification systems: Utilize tyramide signal amplification (TSA) to enhance HRP signal by 10-100 fold. This system converts tyramide substrates into highly reactive intermediates that covalently bind to nearby proteins, significantly increasing localized signal.
Extended substrate incubation: For colorimetric detection, extend DAB substrate incubation to 10-15 minutes while monitoring to prevent excessive background. For chemiluminescence, use extended exposure times with high-sensitivity substrates.
Antibody concentration optimization matrix:
| Sample Type | Starting Dilution | Optimal Range | Incubation Time |
|---|---|---|---|
| Cell lysates | 1:1000 | 1:500-1:2000 | 1-2 hours at RT |
| Tissue sections | 1:200 | 1:100-1:500 | Overnight at 4°C |
| ELISA | 1:2000 | 1:1000-1:5000 | 1-2 hours at RT |
Reduce washing stringency while maintaining specificity by decreasing detergent concentration in wash buffers (0.05% Tween-20 instead of 0.1%) .
When introducing PLAC8.1 antibodies to novel experimental systems, comprehensive validation is essential:
Knockout/knockdown controls: Compare antibody signals between wild-type samples and those with PLAC8 knockdown or knockout. Signal reduction proportional to knockdown efficiency confirms specificity.
Epitope competition assays: Pre-incubate antibody with excess purified PLAC8 protein or immunizing peptide before applying to samples. Signal elimination indicates specific binding.
Multiple antibody validation: Test multiple PLAC8 antibodies targeting different epitopes. Concordant signals strongly suggest specificity.
Molecular weight verification: For Western blotting, PLAC8 should appear at approximately 12.5 kDa . Multiple bands may indicate isoforms, post-translational modifications, or non-specific binding.
Orthogonal technique validation: Compare protein detection with mRNA expression through qPCR or RNA-seq data correlation analysis.
Documentation of these validation steps is critical when publishing research involving novel applications of PLAC8.1 antibodies.
Contradictory results between methods (e.g., positive IHC but negative Western blot) may stem from several factors:
Epitope accessibility: Formalin fixation can mask epitopes recognized by certain antibodies. Implement multiple antigen retrieval methods:
| Antigen Retrieval Method | Protocol | Best For |
|---|---|---|
| Heat-induced (HIER) with citrate | 95°C, 20 min, pH 6.0 | Formalin-fixed tissues |
| Heat-induced with EDTA | 95°C, 20 min, pH 8.0 | Heavily cross-linked samples |
| Enzymatic (pepsin) | 0.05% pepsin, 15 min, 37°C | Surface epitopes |
Protein conformation differences: Native (IHC) versus denatured (WB) states may affect epitope recognition. Try native page for Western blotting to preserve protein folding.
Expression threshold differences: Methods vary in detection sensitivity. Quantify minimum detectable PLAC8 concentration for each method.
Post-translational modifications: These may be tissue-specific and affect antibody binding. Analyze with phosphatase treatment if phosphorylation is suspected.
Cross-reactivity in complex samples: Validate with recombinant PLAC8 protein as positive control alongside tissue samples .
Multiplexing PLAC8.1 detection with other proteins requires careful methodological planning:
For chromogenic multiplexing in IHC:
Sequential detection using antibody stripping between rounds (glycine buffer, pH 2.2, 10 minutes)
Use different chromogens for each target (DAB for HRP-PLAC8.1, Vector Red for alkaline phosphatase conjugates)
Apply spectral unmixing algorithms for quantitative analysis
For fluorescent multiplexing:
Tyramide-based sequential detection allows multiple HRP-conjugated antibodies on the same sample
Protocol sequence:
Apply first HRP-conjugated antibody (PLAC8.1)
Develop with spectrally distinct tyramide (e.g., FITC-tyramide)
Quench HRP activity (3% hydrogen peroxide, 15 minutes)
Apply second HRP-conjugated antibody
Develop with different tyramide (e.g., Cy3-tyramide)
Repeat for additional targets
Cross-reactivity testing between antibodies is essential before multiplexing to ensure signal specificity. Always include single-stained controls for spectral compensation in analysis .
Fixation significantly impacts PLAC8 epitope preservation and accessibility:
| Fixation Method | Impact on PLAC8 Detection | Recommended Tissues |
|---|---|---|
| 10% Neutral Buffered Formalin | Moderate epitope masking; requires HIER | Most tissues; standard for archival samples |
| 4% Paraformaldehyde | Good epitope preservation; mild retrieval needed | Brain, embryonic tissues |
| Methanol/Acetone (1:1) | Excellent for cytoplasmic PLAC8; poor morphology | Cell preparations, frozen sections |
| Bouin's Solution | Strong epitope masking; extended retrieval required | Not recommended for PLAC8 |
For tissues with high lipid content (adipose, brain), shorter fixation times (4-8 hours) improve PLAC8 detection. Extended fixation (>24 hours) significantly reduces signal intensity even with aggressive antigen retrieval. Perfusion fixation provides superior results compared to immersion fixation for PLAC8 detection in highly vascularized tissues .
Quantitative analysis of PLAC8 expression in heterogeneous tissues requires specialized approaches:
Digital pathology workflow:
Whole slide scanning at 20-40x magnification
Tissue segmentation using machine learning algorithms
Cell classification (epithelial, stromal, immune)
PLAC8 intensity measurement within classified regions
Normalized quantification methods:
H-score calculation (percentage of positive cells × intensity category)
Automated positive pixel counting with intensity weighting
Region-specific analysis with normalization to cell density
Statistical considerations:
Minimum analysis of 5-10 high-power fields per sample
Non-parametric testing for intensity distributions (Mann-Whitney)
Multiple testing correction for regional comparisons
Validation approaches:
Correlation with orthogonal methods (qPCR, proteomics)
Biological replicate concordance analysis
Technical replicate variability assessment (<15% coefficient of variation expected)
When reporting PLAC8 quantification, clearly document image acquisition parameters, analysis algorithms, and normalization methods to ensure reproducibility .
PLAC8 demonstrates diverse subcellular localization patterns with distinct functional implications:
Nuclear localization: Often associated with transcriptional regulation and cell cycle control. Quantify as nuclear:cytoplasmic ratio with values >1.5 indicating predominant nuclear function.
Cytoplasmic distribution patterns:
Diffuse: Generally associated with metabolic functions
Punctate: Often indicates vesicular association or protein complex formation
Perinuclear: May suggest Golgi processing or nuclear transport regulation
Membrane association: Indicates potential involvement in signaling cascades or transport processes. Verify with membrane fractionation studies.
Expression dynamics during experimental manipulation:
Stress response: Typically increases cytoplasmic localization
Differentiation: Often shows compartment-specific regulation
Cell cycle: May shuttle between compartments during progression
When evaluating localization, consider co-staining with compartment markers (DAPI for nucleus, phalloidin for actin cytoskeleton, wheat germ agglutinin for membrane) to precisely define distribution patterns. Changes in localization often precede expression level changes during cellular responses and may provide earlier indicators of biological processes .
Single-cell protein analysis with PLAC8.1 antibodies presents unique methodological challenges:
For mass cytometry (CyTOF) applications:
Metal conjugation (typically 147Sm or 153Eu) rather than HRP
Concentration titration critical (typically 0.1-0.5 μg/test)
Validation against flow cytometry results essential
Include spike-in control samples for batch normalization
For microfluidic proteomics platforms:
Higher antibody concentrations generally required (2-5x compared to bulk assays)
Extensive blocking to prevent non-specific adsorption
Sequential incubation with primary-secondary superior to direct conjugates
Temperature control critical for consistent results
Quality control metrics for single-cell applications:
Signal-to-noise ratio >10:1 for reliable detection
Cell recovery >80% to avoid population bias
Coefficient of variation for technical replicates <20%
Correlation with bulk measurements for validation (r>0.8)
Single-cell protein analysis provides critical insights into PLAC8 heterogeneity within populations that bulk measurements cannot resolve, particularly valuable for understanding its role in cellular differentiation and disease progression .
Computational methods significantly enhance PLAC8 expression analysis:
Machine learning for pattern recognition:
Convolutional neural networks for automated localization classification
Random forest algorithms for identifying correlative markers
Support vector machines for patient stratification based on expression patterns
Multi-omics integration approaches:
Correlation of protein expression with transcriptomics data
Network analysis identifying PLAC8 functional associations
Pathway enrichment analysis of co-expressed genes
Data preprocessing requirements:
Batch effect correction using ComBat or similar algorithms
Normalization to account for technical variation
Missing value imputation when appropriate
Visualization techniques:
t-SNE or UMAP for dimensionality reduction
Heatmaps with hierarchical clustering for pattern identification
Correlation networks for identifying functional relationships
These computational approaches transform descriptive PLAC8 expression data into functional hypotheses by identifying patterns and relationships not apparent through conventional analysis. Public database mining (TCGA, GTEx, CCLE) can provide external validation datasets for generated hypotheses .