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CBX5 / Chromobox protein homolog 5 · IHC design guide
Design Immunohistochemistry for CBX5
Plan CBX5 IHC in paraffin sections around the nuclear staining seen in most tissues (HPA tissue IHC). The guide covers controls, antigen retrieval, chromogenic detection and interpretation of staining intensity.
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
CBX5 Immunohistochemistry Experimental Design Guide
Expected localisation, validated protocols, controls and antibodies — the at-a-glance facts below, then the full design guide.
Must know before staining
| Expected localisation | Nuclei in most tissues (HPA tissue IHC) | |
| Staining pattern | Nuclear staining in cells across most tissues (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet M02780-2) | |
| Positive control | Cerebellum+4 more · see all | |
| Negative control | Heart muscle+4 more · see all |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep formalin fixation consistent across sections. (standard IHC practice; not target-specific) | |
| Caveat | Staining and RNA show medium consistency (HPA tissue IHC) | |
| Regulation | Expression regulation not annotated (UniProt) | |
| Isoform / epitope | No annotated isoforms or processing variants (UniProt) |
Section 1
Recommended CBX5 IHC & IF Protocols
The catalog antibody has an IHC-P protocol (datasheet: M02780-2). The following published protocols describe CBX5 staining of tissue microarrays, GBM samples, lung adenocarcinoma tissue, and osteosarcoma tissue (PMC13355934; PMC6658867; PMC3419921; PMC12450695).
| Sample | Paraffin-embedded rat brain tissue; fixative not specified (datasheet M02780-2) |
| Fixation | Image fixative and duration unreported (datasheet M02780-2); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: EDTA pH 8.0 (datasheet M02780-2); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet M02780-2) |
| Primary antibody | Mouse monoclonal (clone 8G6) anti-CBX5, 2μg/ml (datasheet M02780-2) |
| Primary incubation | Overnight at 4 °C (datasheet M02780-2) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet M02780-2) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | CBX5-positive staining in cells in molecular layer of cerebellum (HPA tissue IHC: High). HPA tissue profile: Nuclear expression in most tissues. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA pH 8.0 retrieval for the catalog antibody (datasheet: M02780-2). Published alternatives include citrate pH 6.0 and 1X Trilogy (PMC6658867; PMC3419921).
Section 2
What Is the Expected CBX5 Staining Pattern?
CBX5 is a nuclear, chromatin-associated protein with centromeric and pericentromeric localization (UniProt P45973: subcellular location). In paraffin-section IHC, expect nuclear staining in many cell types, including neuronal cells of the cerebral cortex and placental cytotrophoblasts (HPA tissue IHC: High; nuclear expression in most tissues). HPA rates the tissue profile Enhanced, while noting medium consistency between antibody staining and RNA expression (HPA tissue IHC: reliability description).
| Distinct nuclear staining in cortical neuronal cells or placental cytotrophoblasts. | This matches reported High staining in those cells (HPA tissue IHC: cerebral cortex; placenta). Score the relevant cell nuclei, rather than treating every cell in the section as an equivalent positive control (general IHC practice). |
| Predominantly cytoplasmic or membranous staining with little nuclear signal. | Treat this as a localization mismatch requiring investigation: CBX5 is nuclear and chromatin-associated, and has no transmembrane segment (UniProt P45973: subcellular location; topology). The pattern alone cannot identify the artefact's cause. |
| Strong staining in cardiomyocytes, cholangiocytes, or skeletal myocytes. | These cells were Not detected in the HPA tissue profile (HPA tissue IHC: heart muscle; liver; skeletal muscle). Check possible cross-reactivity or endogenous detection activity before interpreting the staining as CBX5; an HPA negative is an observed reference pattern, not proof that expression is impossible. |
| Diffuse colour across nuclei, cytoplasm, and tissue spaces. | A diffuse deposit does not provide the nuclear contrast expected for CBX5 (UniProt P45973: subcellular location; HPA tissue IHC: nuclear expression). Assess background against a section processed without primary antibody (general IHC practice). |
| No nuclear staining in a reported High cell population. | This conflicts with the HPA reference pattern for, for example, cortical neuronal cells or parathyroid glandular cells (HPA tissue IHC: High). First assess the run's controls and tissue integrity; one blank section cannot establish that CBX5 is absent (general IHC practice). |
💡Expected CBX5 appearanceCall a section positive when the expected cells show clear nuclear staining, potentially strong in HPA High populations such as cortical neurons; dominant cytoplasmic staining or strong staining in HPA Not detected cells calls for investigation (HPA tissue IHC: cerebral cortex, heart muscle; UniProt P45973: subcellular location).
| Cell population selected for assessment | HPA reports High staining in several specific populations, including cerebellar molecular-layer cells and gallbladder glandular cells, but Not detected in cardiomyocytes (HPA tissue IHC). Compare the same cell population when judging controls. |
| Antibody validation for IHC | CAB017548 has an Enhanced IHC validation entry; HPA016699 has no IHC validation entry in the supplied antibody record (HPA antibodies). An ICC Supported entry should not be treated as IHC validation (HPA antibodies). |
| Compartment and protein architecture | CBX5 occupies the nucleus and chromatin, including centromeric heterochromatin (UniProt P45973: subcellular location). Its sequence has no transmembrane segment or signal peptide (UniProt P45973: topology; processing), supporting a nuclear interpretation. |
| Fixation sensitivity | Target-specific effects of fixation or antigen retrieval on CBX5 staining are unreported in the supplied UniProt and HPA records. Select and assess retrieval conditions as a general paraffin-IHC workflow decision, without inferring sensitivity from HPA staining levels. |
| Situation | Likely cause | Next action |
|---|---|---|
| No signal in a reported High population. | The result conflicts with the HPA reference pattern; the section alone does not distinguish technical failure from specimen variation (HPA tissue IHC: High populations). | Review a positive control in the same run, confirm that the primary antibody is IHC-validated, and check retrieval and detection steps (HPA antibodies: CAB017548 IHC Enhanced; general IHC practice). |
| Predominantly cytoplasmic or membranous colour. | The compartment conflicts with nuclear CBX5 localization (UniProt P45973: subcellular location). Nonspecific staining or detection background is possible (general IHC practice). | Compare the suspect signal with a no-primary control, then assess whether the nuclear pattern is reproducible with the IHC-validated antibody (HPA antibodies: CAB017548 IHC Enhanced; general IHC practice). |
| Strong signal in a reported Not detected cell type. | Cross-reactivity or endogenous detection activity may explain staining that conflicts with the HPA observation (HPA tissue IHC: cardiomyocytes, cholangiocytes, skeletal myocytes Not detected). | Examine a no-primary control for detection background and compare staining in a reported High population before assigning the signal to CBX5 (HPA tissue IHC; general IHC practice). |
| Diffuse staining obscures individual nuclei. | Background can prevent assessment of the expected nuclear pattern (UniProt P45973: subcellular location; general IHC practice). Its source cannot be determined from appearance alone. | Check the no-primary control and review blocking, washes, primary-antibody concentration, and detection conditions as general IHC variables; reassess only where nuclei remain distinguishable (general IHC practice). |
| A reported negative cell population is blank. | This can agree with the HPA reference: cardiomyocytes and smooth muscle cells are Not detected (HPA tissue IHC). A blank negative population does not show that the staining run worked. | Use a reported High cell population and the run controls to assess assay performance; record the specific cell type scored (HPA tissue IHC: High and Not detected populations; general IHC practice). |
| IF/ICC: where should CBX5 fluorescence appear? | HPA reports an enhanced nucleoplasmic location in ICC-IF images, consistent with UniProt nuclear localization (HPA subcellular ICC-IF; UniProt P45973: subcellular location). | Interpret fluorescence against a nuclear counterstain and appropriate background control (general IF practice). Use the separate IF/ICC guide for experimental conditions; HPA's ICC Supported status is distinct from IHC validation (HPA antibodies). |
Experiment evidence
IHC & IF images showing CBX5 staining
M02780-2 · IHCIHC analysis of HP1 alpha/CBX5 using anti-HP1 alpha/CBX5 antibody (M02780-2). HP1 alpha/CBX5 was detected in paraffin-embedded section of ra
M02780-2 · IHCIHC analysis of HP1 alpha/CBX5 using anti-HP1 alpha/CBX5 antibody (M02780-2). HP1 alpha/CBX5 was detected in paraffin-embedded section of hu
M02780-2 · IFIF analysis of HP1 alpha/CBX5 using anti-HP1 alpha/CBX5 antibody (M02780-2). HP1 alpha/CBX5 was detected in immunocytochemical section of A5
A02780-3 · IHCIHC analysis of HP1 alpha/CBX5 using anti-HP1 alpha/CBX5 antibody (A02780-3). HP1 alpha/CBX5 was detected in paraffin-embedded section of hu
A02780-3 · IHCIHC analysis of HP1 alpha/CBX5 using anti-HP1 alpha/CBX5 antibody (A02780-3). HP1 alpha/CBX5 was detected in paraffin-embedded section of hu
A02780-3 · IFIF analysis of HP1 alpha/CBX5 using anti-HP1 alpha/CBX5 antibody (A02780-3). HP1 alpha/CBX5 was detected in immunocytochemical section of He
M02780 · IHCIHC analysis of CBX5 using anti-CBX5 antibody (M02780). CBX5 was detected in a paraffin-embedded section of mouse brain tissue. Heat mediate
M02780 · IHCIHC analysis of CBX5 using anti-CBX5 antibody (M02780). CBX5 was detected in a paraffin-embedded section of rat brain tissue. Heat mediated
M02780 · IFImmunofluorescent analysis using the Antibody at 1:50 dilution.
M02780-3 · IHCRat pancreas was stained with anti-HP1α rabbit antibody
M02780-3 · IHCHuman breast carcinoma was stained with anti-HP1α rabbit antibody
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000094916-CBX5/tissue/cerebral+cortex#imid_4424664
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000094916-CBX5/tissue/colon#imid_4424606
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000094916-CBX5/tissue/liver#imid_4424599
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000094916-CBX5/tissue/kidney#imid_4424600
HPA · ICC-IF U-251MGHuman Protein Atlas immunofluorescence, U-251MG, antibody HPA016699; green = CBX5, blue = nucleus, red = microtubules.
HPA · ICC-IF U-251MGHuman Protein Atlas immunofluorescence, U-251MG, antibody HPA016699; green = CBX5, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for CBX5 IHC & IF
🧪Run cerebral cortex first and expect nuclear staining in neuronal cells (HPA: High in cerebral cortex neuronal cells; UniProt P45973: nuclear localization). Use skeletal muscle myocytes as the negative tissue (HPA: Not detected in skeletal muscle myocytes); on the cortex slide, cells without nuclear signal provide a background reference, but the supplied HPA data do not identify a validated negative cell type within that tissue.
Positive control tissue: Cerebellum (Cells in molecular layer, HPA High)
Negative control tissue: Heart muscle (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show CBX5 in U-251MG, U2OS, A-431, with annotated localisation: Nucleoplasm (enhanced) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only slide and a host-species-matched isotype control; the selected antibody is mouse-derived, while its clonality is unreported (selected-SKU tissue-IHC caption: mouse anti-CBX5). Use CBX5-knockout material as a biological specificity control where available, and check endogenous peroxidase and biotin background because the reported brain-section detection uses a biotin-based complex and DAB (selected-SKU tissue-IHC caption: SABC with DAB).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the fixative in the selected-SKU paraffin-section caption is unreported (selected-SKU tissue-IHC caption). The reported rat brain IHC used heat retrieval in EDTA at pH 8.0, so assess retrieval when transferring the method to another specimen preparation (selected-SKU tissue-IHC caption). The supplied evidence does not establish whether frozen sections or IF/ICC are easier; brain pigment can complicate chromogenic interpretation, so judge signal by its expected nuclear location (UniProt P45973: nuclear localization).
HPA tissue IHC evidence for CBX5
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — Medium consistency between antibody staining and RNA expression data.). Rows are taken directly from the HPA tissue chart — click any row's HPA link to view the source.
Positive expression · recommended positive controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Cerebellum | Cells in molecular layer | High | Protein (IHC) | HPA → |
| Cerebral cortex | Neuronal cells | High | Protein (IHC) | HPA → |
| Gallbladder | Glandular cells | High | Protein (IHC) | HPA → |
| Hippocampus | Glial cells | High | Protein (IHC) | HPA → |
| Parathyroid gland | Glandular cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Heart muscle | Cardiomyocytes | Not detected | Protein (IHC) | HPA → |
| Liver | Cholangiocytes | Not detected | Protein (IHC) | HPA → |
| Skeletal muscle | Myocytes | Not detected | Protein (IHC) | HPA → |
| Smooth muscle | Smooth muscle cells | Not detected | Protein (IHC) | HPA → |
| Soft tissue | Chondrocytes | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced CBX5 IHC Tips
Troubleshoot chromogenic CBX5 IHC by checking retrieval, nuclear localisation, staining controls and scoring before interpreting tissue differences.
What retrieval should I start with for weak CBX5 staining in paraffin sections?
Start with heat mediated retrieval in EDTA at pH 8.0 for paraffin sections (datasheet M02780-2). The selected antibody detected CBX5 in rat brain after that retrieval, followed by 10% goat serum blocking and 2 µg/mL primary antibody overnight at 4°C (datasheet M02780-2). If nuclear staining remains weak, compare shorter and longer heating while keeping buffer, detection and section handling consistent (standard IHC practice). Assess morphology alongside signal, because excessive heating can damage sections and make nuclear staining difficult to interpret (standard IHC practice). Include a known positive section in each comparison, such as the documented rat brain preparation (datasheet M02780-2).
Could fixation explain weak or uneven CBX5 staining?
Target specific fixation sensitivity is unknown: the selected paraffin section caption does not state a fixative (datasheet M02780-2). Record fixative, fixation duration and tissue thickness for each specimen, then compare sections processed under matched conditions (standard IHC practice). If staining varies, repeat the documented EDTA pH 8.0 retrieval and 2 µg/mL overnight primary incubation on both specimens before attributing the difference to fixation (datasheet M02780-2; standard IHC practice). Inspect nuclear detail and section edges for processing artefacts, and use an independently processed positive section to check the staining run (standard IHC practice). Nuclear localisation or reported CBX5 modifications do not establish how this antibody responds to a particular fixative (UniProt P45973).
Where should convincing CBX5 chromogenic staining appear?
Score staining within nuclei: CBX5 is annotated in nuclei and on chromosomes, including centromeric and pericentromeric heterochromatin (UniProt P45973). Tissue IHC reports nuclear expression in most tissues, while cell imaging places CBX5 in the nucleoplasm (HPA tissue IHC; HPA subcellular). Expect the appearance of nuclear staining to vary with cell cycle and chromatin organization, since CBX5 associates with chromosomes during mitosis (UniProt P45973; standard IHC practice). Compare DAB signal with the counterstained nuclear boundary at matched exposure and development conditions, and investigate prominent diffuse cytoplasmic signal before scoring it as positive (standard IHC practice). A no primary control can help distinguish detection background from nuclear antigen signal (standard IHC practice).
How should I investigate an unexpected staining pattern when the antibody epitope is unspecified?
The supplied record lists 0 annotated isoforms, but it does not identify the selected antibody’s binding epitope (UniProt P45973; datasheet M02780-2). CBX5 has a chromo domain at residues 20–78, a chromoshadow domain at 121–179, and reported modified residues near its N terminus (UniProt P45973). Those features give reasons to test epitope accessibility, but they do not show that a modification alters this antibody’s staining (UniProt P45973; standard IHC practice). Keep the documented EDTA pH 8.0 retrieval as the baseline and compare any retrieval changes on adjacent sections (datasheet M02780-2; standard IHC practice). If available, compare a separately validated antibody with a known epitope and inspect agreement in nuclear distribution (standard IHC practice).
How can I use IF to check a puzzling CBX5 IHC result?
Treat IF as a separate assay: the selected antibody’s supplied tissue evidence documents chromogenic staining of paraffin sections, while the IF images listed for CBX5 are separate HPA observations (datasheet M02780-2; HPA subcellular). Multiplex CBX5 with a validated marker for the cell population being evaluated, and use a DNA counterstain to assess nuclear overlap (standard IF practice; UniProt P45973 localisation). Select fluorophores after inspecting unstained tissue autofluorescence, placing the weaker signal in a cleaner spectral channel (standard IF practice). CBX5 has no transmembrane segment and is nuclear, so use controlled permeabilisation that permits nuclear antibody access while preserving morphology (UniProt P45973; standard IF practice). Include single stain and no primary controls when judging overlap and background (standard IF practice).
What should I check when DAB appears outside CBX5 positive nuclei?
First distinguish diffuse DAB from the predominantly nuclear pattern reported for CBX5 in tissue IHC (HPA tissue IHC). The documented workflow used 10% goat serum, 2 µg/mL primary antibody overnight at 4°C, a biotinylated secondary for 30 minutes at 37°C, and a streptavidin biotin detection system with DAB (datasheet M02780-2). Check no primary and secondary only controls, endogenous peroxidase blocking, wash quality and DAB development as general chromogenic IHC troubleshooting steps (standard IHC practice). With biotin based detection, an appropriate endogenous biotin control can clarify staining unrelated to antibody binding (standard IHC practice). Reassess any remaining signal against nuclear boundaries before changing the primary concentration (standard IHC practice).
How should I quantify CBX5 staining across tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and region before scoring, then report the percentage of positive nuclei and an intensity based H score (standard IHC practice). An H score can use 0–3 intensity categories and sum each intensity multiplied by its percentage of cells, giving a 0–300 range (standard IHC practice). Normalise positive counts to the number of evaluable nuclei in the same region; if reporting density, use positive nuclei per mm² of evaluable tissue (standard IHC practice). Keep retrieval, DAB development, counterstain and scoring thresholds matched across sections (standard IHC practice). Analyse relevant cell populations separately because HPA reports different CBX5 staining levels among annotated tissue cell types (HPA tissue IHC).
How can I distinguish true CBX5 signal from a staining artefact?
A credible positive has signal within intact nuclear boundaries, consistent with CBX5’s nuclear and chromosomal localisation and the predominantly nuclear tissue pattern (UniProt P45973; HPA tissue IHC). Check the annotated cell population: HPA reports high staining in cerebral cortex neuronal cells and no detection in heart muscle cardiomyocytes, so tissue identity alone cannot establish positivity (HPA tissue IHC). Treat staining concentrated at section edges, necrotic areas or damaged nuclei cautiously, and inspect a no primary control for nonspecific detection (standard IHC practice). Exclude endogenous peroxidase related DAB signal with a suitable control before counting positive nuclei (standard IHC practice). Interpret discordant cases alongside morphology, controls and HPA’s reported medium consistency between staining and RNA expression (HPA tissue IHC).
Boster reagents
Best CBX5 / Chromobox protein homolog 5 IHC Antibodies
Anti-CBX5 antibodies have IHC images from human, mouse and rat paraffin sections, and IF/ICC images from human HeLa and A549 cells (catalog image captions).
Real IHC data
Anti-HP1 alpha/CBX5 Antibody ® (monoclonal, 8G6)
Cat # M02780-2
Real IHC data
Anti-HP1 alpha/CBX5 Antibody ®
Cat # A02780-3
Real IHC data
Anti-HP1 alpha CBX5 Rabbit Monoclonal Antibody
Cat # M02780
Real IHC data
Anti-HP1α Rabbit Monoclonal Antibody
Cat # M02780-3
M02780-2 has IHC images from rat brain and three human tumors; A02780-3 has IHC images from human lung and mammary cancers and mouse intestine (catalog IHC captions). M02780 has IHC images from mouse and rat brain; M02780-3 has IHC images from rat and mouse pancreas and human breast carcinoma (catalog IHC captions).
Which to pick: For tissue IHC, start with A02780-3: its caption documents staining of paraffin sections of human lung cancer at 1 μg/ml after EDTA pH 8.0 retrieval; the fixative is unreported (A02780-3 IHC caption). For IF/ICC, M02780-2 is a mouse monoclonal with a documented A549 cell IF image (M02780-2 catalog and IF caption). For work spanning human, mouse and rat tissue, consider the rabbit monoclonal M02780-3: its IHC captions show human breast carcinoma and mouse and rat pancreas, though they do not report fixation or processing conditions (M02780-3 catalog and IHC captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P45973 (CBX5_HUMAN, Chromobox protein homolog 5).
- Human Protein Atlas. CBX5 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. CBX5 subcellular location (ICC-IF): Localized to the nucleoplasm..
- Human Protein Atlas. CBX5 antibody validation summary (2 antibodies).
- Psychological Stress Associated Bile Acid Reprogramming Promotes Hepatocellular Carcinoma Progression. Advanced science (Weinheim, Baden-Wurttemberg, Germany) 2026 — PMC13355934.
- Acquired temozolomide resistance in MGMT-deficient glioblastoma cells is associated with regulation of DNA repair by DHC2. Brain : a journal of neurology 2019 — PMC6658867.
- Network biology of tumor stem-like cells identified a regulatory role of CBX5 in lung cancer. Scientific reports 2012 — PMC3419921.
- Identification of MAEA protein as a potential target for chemoresistance in osteosarcoma using bioinformatics and proteomic analysis. Frontiers in oncology 2025 — PMC12450695.
- PubMed PMID:8505380 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
- PubMed PMID:15489334 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for CBX5 (Chromobox protein homolog 5). Expected localisation Nuclei in most tissues (HPA tissue IHC). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet M02780-2). Validated IHC antibody: M02780-2 at 2μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Cerebellum (Cells in molecular layer); negative Heart muscle. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded rat brain tissue; fixative not specified (datasheet M02780-2); 2. Fixation: Image fixative and duration unreported (datasheet M02780-2); verify before use.; 3. Sectioning: 4–5 µm sections on charged slides (standard); 4. Deparaffinisation: Xylene, graded ethanol series to water (standard); 5. Antigen retrieval: Heat retrieval: EDTA pH 8.0 (datasheet M02780-2); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet M02780-2); 8. Primary antibody: Mouse monoclonal (clone 8G6) anti-CBX5, 2μg/ml (datasheet M02780-2); 9. Primary incubation: Overnight at 4 °C (datasheet M02780-2). Watch for: Fixation: Keep formalin fixation consistent across sections. (standard IHC practice; not target-specific); Caveat: Staining and RNA show medium consistency (HPA tissue IHC); Isoform / epitope: No annotated isoforms or processing variants (UniProt); Regulation: Expression regulation not annotated (UniProt). Evidence: UniProt P45973, HPA tissue IHC · Enhanced, HPA ICC-IF · nucleoplasm., Datasheet M02780-2, PMC13355934, PMC6658867. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/CBX5/immunohistochemistry-ihc-guide.