FITC conjugation involves covalent bonding between the isothiocyanate group of FITC and primary amines (e.g., lysine residues) on the antibody. Key steps include:
Antibody Preparation: Dialyze purified CYBA antibody (≥1 mg/mL) against carbonate-bicarbonate buffer (pH 9.2) to remove interfering ions.
FITC Labeling: Add FITC dissolved in DMSO (20 μL of 5 mg/mL FITC per mg antibody). Incubate 2 hrs at RT.
Purification: Remove unbound FITC via gel filtration or dialysis.
Quality Control: Calculate fluorochrome-to-protein (F/P) ratio using absorbance at 280 nm (protein) and 492 nm (FITC). Optimal F/P: 5–6:1 .
Specificity: CYBA-FITC antibodies show no cross-reactivity with unrelated proteins in western blotting .
Sensitivity: Detects CYBA at concentrations as low as 0.1 ng/mL in ELISA .
Flow Cytometry: Validated in competitive binding assays (e.g., 92–100% binding efficiency in EGFR studies) .
| Supplier | Catalog No. | Host | Conjugate | Price (USD) |
|---|---|---|---|---|
| Antibodies.com | ABIN1042638 | Mouse | Unconjugated | N/A |
| Antibodies.com | ABIN656083 | Rabbit | Unconjugated | N/A |
| Proteintech | SA00003-2 | Goat | FITC | $40/0.6 mg |
Note: Custom FITC conjugation services are widely available for unconjugated CYBA antibodies .
CYBA (Cytochrome b-245 light chain) is a crucial component of the NADPH oxidase complex, also known as Cytochrome b(558) alpha chain, Neutrophil cytochrome b 22 kDa polypeptide, or p22-phox. This 22 kDa protein forms part of the superoxide-generating NADPH oxidase system in phagocytes, making it central to understanding oxidative stress responses, immune cell function, and related pathologies. The CYBA gene (UniProtID: P13498) encodes this protein which is essential for proper electron transport during respiratory burst in neutrophils and macrophages . Research targeting CYBA is particularly valuable in studying chronic granulomatous disease, cardiovascular conditions, and inflammatory responses where reactive oxygen species play significant roles.
FITC (Fluorescein isothiocyanate) conjugation involves covalently linking the fluorescent FITC molecule to antibodies, creating a detectable reporter system. FITC is a derivative of fluorescein with an isothiocyanate reactive group (-N=C=S) that binds to primary amines on proteins . FITC-conjugated antibodies exhibit excitation and emission peak wavelengths of approximately 495 nm and 519 nm respectively, producing a bright green fluorescence . This conjugation enables direct visualization of antibody-antigen interactions without requiring secondary detection systems. FITC-conjugated antibodies maintain stable fluorescence properties when properly stored at -20°C and protected from light exposure. The FITC conjugation to the CYBA antibody preserves the antibody's target specificity while enabling fluorescent detection in applications such as flow cytometry, immunofluorescence microscopy, and fluorescent ELISA .
The FITC-conjugated CYBA antibody differs from non-conjugated versions in several important aspects. The conjugation process adds the fluorophore directly to the antibody molecule, increasing its molecular weight and potentially altering its solubility and buffer compatibility. The FITC-conjugated version is supplied in a specialized buffer system containing 50% glycerol, 0.01M PBS at pH 7.4, with 0.03% Proclin 300 as a preservative . Unlike non-conjugated antibodies that require secondary detection reagents, the FITC-conjugated CYBA antibody enables direct detection in fluorescence-based assays. The conjugation ratio (number of FITC molecules per antibody) is optimized to provide bright signal while minimizing potential interference with antigen binding. Researchers should note that the FITC conjugation may slightly reduce binding affinity compared to unconjugated versions, although manufacturers typically validate that the conjugated antibody maintains specific target recognition.
Validation of CYBA Antibody, FITC conjugated typically involves a multi-parameter approach. Manufacturers employ affinity purification using Protein G to achieve >95% purity before conjugation . Specificity is confirmed using ELISA against the recombinant human CYBA immunogen (amino acids 128-195) . Flow cytometry validation uses positive controls (cells known to express CYBA) and negative controls (CYBA-knockout cells or isotype controls) to verify target-specific binding. Western blot analysis confirms detection of the appropriate molecular weight band (approximately 22 kDa). Immunofluorescence microscopy validation demonstrates the expected subcellular localization pattern of CYBA, particularly in phagocytic cells. Cross-reactivity testing with related proteins helps ensure the antibody does not bind unintended targets. Batch-to-batch consistency testing confirms reproducible performance across manufacturing lots. Researchers should review the validation data provided by manufacturers and consider performing their own validation in their specific experimental system before conducting critical experiments.
Optimizing immunofluorescence with CYBA Antibody, FITC conjugated for challenging tissue samples requires systematic protocol modifications. For tissues with high autofluorescence, implement a pre-treatment with 0.1% Sudan Black B in 70% ethanol for 20 minutes followed by extensive PBS washing. Antigen retrieval methods should be empirically tested, comparing heat-induced epitope retrieval (in citrate buffer pH 6.0 or Tris-EDTA pH 9.0) against enzymatic retrieval methods. When working with fixed tissues showing poor antibody penetration, extend the incubation time to 24-48 hours at 4°C with gentle agitation, and consider using a detergent-enhanced buffer system (0.3% Triton X-100 in PBS with 1% BSA). For multi-labeling experiments where spectral overlap is a concern, use sequential staining protocols and appropriate compensation controls. The antibody concentration should be titrated specifically for each tissue type, typically starting at 1:50 dilution and preparing a dilution series to determine optimal signal-to-noise ratio. For quantitative studies, always include unstained, isotype, and single-color controls to establish thresholds and account for tissue-specific background. Confocal microscopy with appropriate filter sets (excitation 488 nm, emission 520 nm) will provide optimal visualization of the FITC signal with minimal bleed-through.
When analyzing rare cell populations with CYBA Antibody, FITC conjugated, several critical factors must be addressed. First, implement rigorous pre-analytical sample preparation to minimize cell loss—use gentle centrifugation speeds (300-400×g) and pre-coat tubes with 2% BSA to prevent cell adhesion. For intracellular CYBA detection, optimize permeabilization conditions, comparing commercial permeabilization reagents to find the balance between epitope accessibility and cellular integrity. Develop a multi-parameter gating strategy incorporating lineage-specific markers alongside CYBA to accurately identify target populations. When analyzing rare events (frequency <0.1%), collect at least 1-3 million total events to ensure statistical significance, and verify results using fluorescence-minus-one (FMO) controls. To distinguish true CYBA signal from autofluorescence, include a viability dye and implement dump channels to exclude dead cells and unwanted populations. Consider using spectral flow cytometry for improved resolution or fluorescence-activated cell sorting for subsequent functional analysis of CYBA-positive cells. For longitudinal studies, establish robust quality control measures including calibration beads and daily instrument performance checks to ensure data comparability across time points.
Addressing potential interference between FITC conjugation and CYBA epitope recognition requires a systematic experimental approach. First, perform parallel experiments comparing FITC-conjugated CYBA antibody with unconjugated primary followed by fluorescent secondary antibody detection, analyzing signal intensity, background, and staining pattern. Epitope mapping studies can identify whether the conjugation affects critical binding regions—employ peptide competition assays using overlapping peptides spanning the immunogen sequence (amino acids 128-195 of human CYBA) to determine if FITC conjugation alters specific epitope recognition. To assess whether steric hindrance is affecting antibody penetration in tissue sections, test varying fixation conditions and antigen retrieval methods, as overfixation may exacerbate accessibility issues with conjugated antibodies. For applications requiring maximal sensitivity, consider using signal amplification systems such as tyramide signal amplification compatible with FITC detection. In multiplexed experiments, evaluate whether antigen order of staining affects signal intensity, as sequential staining may be preferable to simultaneous application when working with conjugated antibodies targeting sterically challenging epitopes. Additionally, validate findings using alternative detection methods such as proximity ligation assay to confirm specificity when epitope interference is suspected.
Quantification of CYBA expression using FITC-conjugated antibodies requires proper calibration and standardization. Implement quantitative flow cytometry using calibration beads with known FITC molecules of equivalent soluble fluorochrome (MESF) to convert fluorescence intensity into absolute units. The following table demonstrates a typical calibration curve for FITC quantification:
| MESF Standard | Mean Fluorescence (FL1) | CV (%) |
|---|---|---|
| Blank | 2.1 | 3.2 |
| Standard 1 | 5,245 | 4.1 |
| Standard 2 | 15,876 | 3.8 |
| Standard 3 | 36,990 | 2.9 |
| Standard 4 | 154,567 | 3.5 |
For quantitative immunofluorescence microscopy, perform parallel staining of calibration slides containing reference cells with known CYBA expression levels. Develop automated image analysis workflows that segment cells, subtract background, and measure integrated fluorescence intensity. For relative quantification across experimental conditions, use standardized acquisition parameters and include internal reference standards in each experiment. When absolute quantification is required, consider complementary approaches such as quantitative Western blotting or mass cytometry. For single-cell analysis, implement high-content imaging systems to correlate CYBA expression with morphological features or other biomarkers. Statistical analysis should include appropriate controls for autofluorescence, and results should be validated using orthogonal methods such as quantitative PCR for CYBA mRNA levels.
Designing experiments to study CYBA function with FITC-conjugated antibodies requires careful consideration of biological context and technical constraints. Begin with clear hypothesis formulation based on CYBA's role in the NADPH oxidase complex. Include appropriate biological controls—positive controls (neutrophils or macrophages with known NADPH oxidase activity), negative controls (cells treated with NADPH oxidase inhibitors or from CGD patients), and isotype controls to establish baseline fluorescence. For functional studies, pair CYBA antibody staining with reactive oxygen species (ROS) detection assays such as dihydroethidium (DHE) or 2',7'-dichlorofluorescin diacetate (DCFDA). When studying stimulated conditions, standardize stimulation protocols (e.g., PMA concentration, incubation time) across experimental replicates. For co-localization studies, combine CYBA-FITC with antibodies against other NADPH oxidase components (gp91phox, p47phox) using compatible fluorophores. Implement time-course experiments to capture dynamic changes in CYBA distribution during cellular activation. For mechanistic studies, integrate CYBA staining with inhibitor treatments or genetic perturbations (siRNA, CRISPR) targeting regulatory pathways. Power calculations should determine appropriate sample sizes, typically requiring at least 3-5 biological replicates per condition. Document detailed protocols including fixation conditions, antibody concentrations, and image acquisition parameters to ensure reproducibility.
When encountering weak or non-specific signals with CYBA Antibody, FITC conjugated, implement a systematic troubleshooting approach. For weak signals, first verify antibody viability—FITC is photosensitive, so confirm proper storage away from light at -20°C . Optimize antibody concentration through titration experiments, typically testing 2-fold dilutions from 1:25 to 1:800. Enhance signal detection by extending incubation time (overnight at 4°C) or improving permeabilization for intracellular targets. For high background or non-specific binding, implement more stringent blocking (5% BSA with 5% normal serum matching the host species of cells) and increase washing steps (5-6 washes of 5 minutes each). If autofluorescence is present, include 0.1-0.3% Sudan Black B treatment post-fixation or use alternative detection methods. For flow cytometry, optimization of voltage settings and compensation is critical. The following table outlines common issues and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No signal | Antibody degradation | Use fresh aliquot, verify with positive control |
| Inadequate permeabilization | Optimize detergent concentration and time | |
| Target not expressed | Verify expression with alternative methods | |
| High background | Insufficient blocking | Increase blocking reagent concentration and time |
| Non-specific binding | Pre-adsorb antibody, increase washing stringency | |
| Autofluorescence | Use Sudan Black B, switch to far-red fluorophores | |
| Inconsistent results | Variable fixation | Standardize fixation protocol, time, and temperature |
| Batch variation | Use same lot number, include internal standards |
If problems persist, verify antibody specificity using knockout controls or peptide competition assays.
Integrating CYBA Antibody, FITC conjugated into multiplexed immunofluorescence requires strategic panel design. First, select compatible fluorophores that minimize spectral overlap with FITC's emission spectrum (519 nm)—ideal partners include PE (emission ~575 nm), APC (emission ~660 nm), and far-red dyes (emission >700 nm). Perform single-color controls to establish compensation matrices, particularly important for flow cytometry applications. When designing microscopy panels, consider the excitation laser lines available and prioritize channel assignment based on target abundance (place less abundant targets in brighter channels). For tissue sections, implement sequential staining protocols to minimize antibody cross-reactivity, particularly when multiple rabbit-derived antibodies are used. Validate multiplexed panels incrementally, adding one marker at a time to identify potential interactions. For panels exceeding 4-5 colors, consider spectral unmixing algorithms to resolve overlapping emission profiles. Implement consistent nomenclature and standardized acquisition settings across experiments. For quantitative analysis, include fluorescence minus one (FMO) controls for each marker to establish accurate gating boundaries. When studying cellular interactions, combine CYBA staining with lineage-specific markers and functional readouts such as phospho-protein detection. For high-dimensional analysis, consider computational approaches such as tSNE or UMAP to visualize complex cellular phenotypes in relation to CYBA expression patterns.
Interpreting CYBA expression patterns requires contextualizing results within cellular activation frameworks. In resting neutrophils and macrophages, CYBA (p22-phox) typically shows a diffuse cytoplasmic distribution with some membrane localization. Upon cellular activation (e.g., with PMA, fMLP, or pathogen exposure), researchers should observe increased membrane translocation corresponding with NADPH oxidase complex assembly. Quantitative analysis should measure not only total CYBA signal intensity but also subcellular distribution patterns using colocalization coefficients with membrane markers. Different activation stimuli may produce distinct temporal patterns of CYBA redistribution—rapid translocation (minutes) typically occurs with direct PKC activators, while slower responses (hours) may accompany differentiation or polarization processes. Heterogeneity in cellular responses should be quantified using single-cell analysis approaches rather than population averages. When analyzing tissue samples, consider the microenvironmental context, as hypoxia, pH changes, and neighboring cell interactions can modulate CYBA expression and localization. For disease-related studies, compare CYBA patterns in pathological samples with appropriate controls matched for age, sex, and relevant clinical parameters. Statistical analysis should employ appropriate tests for the data distribution (parametric vs. non-parametric) and account for multiple comparisons when analyzing complex phenotypes. Integration with functional readouts such as ROS production measurements provides the most comprehensive understanding of CYBA's biological significance in different activation states.
Differentiating specific CYBA-FITC signal from autofluorescence requires both experimental and analytical approaches. Experimentally, implement autofluorescence quenching treatments such as Sudan Black B (0.1% in 70% ethanol) or commercially available quenching reagents specifically designed for tissues with high endogenous fluorescence (e.g., liver, brain). When working with fixed tissues or cells containing lipofuscin (common in aging tissues), photo-bleaching the sample prior to antibody application can reduce background (expose to intense light source with appropriate FITC filter for 1-2 minutes). Analytically, employ spectral unmixing algorithms that can separate the FITC emission profile from autofluorescence based on their distinct spectral signatures. Multi-exponential lifetime imaging (FLIM) offers another approach, as antibody-conjugated FITC typically has a different fluorescence lifetime than endogenous fluorophores. For flow cytometry applications, include unstained controls from each experimental condition and use matched isotype-FITC controls to set positive/negative thresholds. The following analytical workflow can be implemented:
Collect data in unstained and single-stained samples across all channels
Generate autofluorescence profile for each sample type
Apply computational correction algorithms (e.g., autofluorescence subtraction)
Validate threshold settings using known positive and negative controls
Implement Boolean gating strategies that incorporate multiple parameters to confirm true positive events
This combined approach significantly improves signal-to-noise ratio, particularly in challenging samples such as lung tissue or macrophages with high intrinsic autofluorescence.
Quantitative comparison of CYBA expression across experimental conditions requires standardized data acquisition and analysis protocols. For flow cytometry, implement calibration with quantitative beads to convert mean fluorescence intensity (MFI) to molecules of equivalent soluble fluorochrome (MESF), enabling absolute quantification independent of instrument settings. Always process samples from different experimental conditions simultaneously with identical antibody concentrations, incubation times, and acquisition parameters. For image-based analysis, standardize exposure settings, gain, and offset values across all samples, and include fluorescence calibration slides in each imaging session. Develop automated image analysis pipelines that perform consistent cell segmentation, background subtraction, and intensity measurement. When comparing across multiple experiments, include internal reference standards (e.g., a standard cell line) in each experiment for normalization. Statistical analysis should account for the hierarchical nature of the data (cells within samples within experimental conditions) using mixed-effects models rather than simple t-tests or ANOVA. The following table demonstrates a normalization approach for cross-experimental comparisons:
| Experiment | Raw CYBA MFI (Control) | Raw CYBA MFI (Treatment) | Normalized Ratio (Treatment/Control) |
|---|---|---|---|
| 1 | 4,532 | 9,876 | 2.18 |
| 2 | 5,123 | 10,452 | 2.04 |
| 3 | 3,987 | 8,654 | 2.17 |
| Mean ± SD | 4,547 ± 568 | 9,661 ± 916 | 2.13 ± 0.08 |
This normalization approach controls for day-to-day variations in instrument performance while preserving the biological effect size. For time-course experiments, area-under-curve analysis or mixed-effects modeling for repeated measures provides more robust comparisons than individual time point analyses.
Analyzing colocalization between CYBA-FITC and other fluorescently labeled proteins requires rigorous methodology to generate reliable results. Begin with proper image acquisition—use sequential scanning rather than simultaneous acquisition to prevent bleed-through, and ensure optimal sampling by adhering to Nyquist criteria (pixel size ≤1/2 resolution limit). Before analysis, apply appropriate pre-processing steps including background subtraction, deconvolution (if applicable), and chromatic aberration correction using multicolor beads. For quantitative colocalization, employ multiple complementary metrics: Pearson's correlation coefficient (PCC) measures intensity correlation (-1 to +1), Manders' overlap coefficients (M1 and M2) quantify proportional overlap (0 to 1), and object-based approaches count instances of spatial coincidence. The table below provides interpretation guidelines for colocalization coefficients:
| Coefficient Value | Pearson's Interpretation | Manders' Interpretation |
|---|---|---|
| 0.7 to 1.0 | Strong colocalization | High overlap |
| 0.4 to 0.7 | Moderate colocalization | Moderate overlap |
| 0.2 to 0.4 | Weak colocalization | Low overlap |
| -0.2 to 0.2 | No colocalization | Random overlap |
| -0.7 to -0.2 | Weak exclusion | N/A |
| -1.0 to -0.7 | Strong exclusion | N/A |
Include appropriate controls: positive controls (dual-labeled single protein), negative controls (proteins known to occupy distinct compartments), and random controls (digitally randomized image overlays). For dynamics studies, implement live-cell imaging with photostable fluorophores and analyze temporal correlation. When studying membrane proteins, consider super-resolution techniques (STED, PALM, STORM) to overcome diffraction limitations. Statistical analysis should compare colocalization metrics across experimental conditions using appropriate tests and include sufficient biological replicates (minimum n=3) with multiple fields of view per replicate.
CYBA Antibody, FITC conjugated offers powerful capabilities for investigating oxidative stress in cardiovascular disease models. In atherosclerosis research, implement multi-parameter flow cytometry panels combining CYBA-FITC with markers for specific vascular cell populations (endothelial cells: CD31; smooth muscle cells: α-SMA; macrophages: CD68) to track cell-specific NADPH oxidase activity. For tissue-based studies, perform immunofluorescence on vascular sections, analyzing CYBA distribution in relation to atherosclerotic plaque progression. In hypertension models, quantify CYBA expression in resistance vessels using confocal microscopy, correlating with vascular remodeling metrics and blood pressure measurements. For mechanistic investigations, combine CYBA staining with phospho-specific antibodies targeting activation pathways (PKC, Rac1) to elucidate signaling cascades. In ischemia-reperfusion models, track the temporal dynamics of CYBA redistribution and activation during the reperfusion phase, implementing intravital microscopy when feasible. Functional correlation requires parallel assays measuring superoxide production (e.g., dihydroethidium fluorescence or lucigenin chemiluminescence) alongside CYBA localization. For translational relevance, compare findings between animal models and human samples (e.g., vascular biopsies, isolated leukocytes from patients with cardiovascular disease). Advanced applications include single-cell transcriptomics combined with index sorting of CYBA-FITC labeled cells to correlate protein expression with transcriptional profiles in heterogeneous vascular cell populations.
Emerging technologies are revolutionizing applications of FITC-conjugated CYBA antibodies in research. Super-resolution microscopy techniques (STED, STORM, PALM) overcome the diffraction limit (approximately 200 nm) to resolve nanoscale organization of CYBA within membrane microdomains, critically important for understanding NADPH oxidase complex assembly. Lattice light-sheet microscopy enables long-term 4D imaging of CYBA dynamics in living cells with minimal phototoxicity. Mass cytometry (CyTOF) with metal-tagged antibodies against CYBA can be combined with dozens of other markers for high-dimensional phenotyping without fluorescence spillover concerns. Spatial transcriptomics technologies allow correlation of CYBA protein localization with gene expression patterns in intact tissues. Expansion microscopy physically enlarges specimens after CYBA-FITC labeling, providing enhanced resolution on standard microscopes. Microfluidic systems enable real-time analysis of CYBA trafficking during controlled cellular stimulation. For quantitative applications, smFRET (single-molecule Förster Resonance Energy Transfer) between FITC-CYBA and complementary labeled NADPH oxidase components provides direct measurement of molecular interactions at nanometer scale. Advanced computational approaches include deep learning algorithms for automated detection and classification of CYBA distribution patterns, and agent-based modeling to predict CYBA behavior based on experimental data. CRISPR-based gene editing combined with FITC-CYBA antibodies facilitates precise correlation between genetic variants and protein function in isogenic cell systems.
Integrating CYBA-FITC antibody data with multi-omics approaches creates a comprehensive systems biology framework. Begin by combining single-cell proteomics and CYBA-FITC flow cytometry through index sorting, where cells are analyzed by flow cytometry for CYBA expression before individual cell sequencing. This links CYBA protein levels directly to transcriptional profiles. For spatial context, implement multiplexed immunofluorescence with CYBA-FITC alongside transcriptomics using technologies such as Geo-seq or 10X Visium, correlating spatial CYBA distribution with local transcriptional programs. Integration with metabolomics requires careful experimental design—analyze metabolite profiles in CYBA-high versus CYBA-low sorted cell populations to identify metabolic signatures associated with NADPH oxidase activity. Epigenomic integration can reveal regulatory mechanisms controlling CYBA expression through techniques like CUT&TAG or ATAC-seq on sorted cell populations. The following analytical workflow maximizes multi-omics integration:
Generate paired datasets (e.g., CYBA-FITC flow cytometry + RNA-seq from the same samples)
Implement data normalization appropriate for each platform
Perform dimensionality reduction to identify major sources of variation
Apply multi-omics integration algorithms (MOFA+, mixOmics, DIABLO)
Validate predicted interactions using targeted experiments
For clinical translation, correlate CYBA expression patterns with patient-derived multi-omics data and clinical outcomes. Network analysis tools can then model the relationships between CYBA, interacting proteins, transcriptional regulators, and downstream effectors. This systems approach generates testable hypotheses about CYBA's role in complex biological processes like inflammation resolution or redox-sensitive cellular adaptations.
Longitudinal studies using CYBA Antibody, FITC conjugated require careful planning to ensure data consistency and reliability over time. First, create a master antibody bank by purchasing sufficient antibody from a single manufacturing lot, aliquoting appropriately to minimize freeze-thaw cycles, and storing at -20°C protected from light . Implement rigorous quality control measures including regular antibody performance testing against reference standards and inclusion of internal controls in each experimental time point. For flow cytometry applications, establish a standardized panel that includes CYBA-FITC alongside stable reference markers, and use calibration beads to normalize fluorescence intensity across instruments and time points. When analyzing tissue samples collected over time, standardize every aspect of the workflow—fixation duration, antigen retrieval conditions, antibody concentration, and incubation times. Documentation is critical: maintain detailed protocols, reagent information, instrument settings, and analysis parameters in a laboratory information management system. For long-term cell culture experiments, carefully control passage number, confluency, and culture conditions to minimize phenotypic drift. Statistical analysis should employ mixed-effects modeling approaches that account for both biological variability and technical factors. When personnel changes occur during the study, implement formal training and validation procedures to ensure consistent technique. For clinical studies, consider establishing a centralized sample processing core to minimize site-to-site variability. These systematic approaches maximize the reliability of longitudinal CYBA expression data for detecting true biological changes while minimizing technical artifacts.