This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
ASF1B / Histone chaperone ASF1B · IHC design guide
Design Immunohistochemistry for ASF1B
Plan chromogenic IHC for ASF1B in paraffin sections with the catalog antibody at 1:100–1:300 (datasheet A05211). Assess nuclear staining in testis spermatogonia and use adipose tissue as a negative reference (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
ASF1B 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 | Nuclear staining in tissue IHC (HPA tissue IHC) | |
| Staining pattern | Nuclear staining in testis spermatogonia (HPA tissue IHC) | |
| Antigen retrieval | Tris-EDTA pH 9.0 HIER, heat-mediated (datasheet A05211) | |
| Positive control | Cerebral cortex+4 more · see all | |
| Negative control | Adipose tissue+4 more · see all |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image A05211) | |
| Caveat | Antibody staining and RNA show medium consistency (HPA tissue IHC) | |
| Regulation | Testis-high; lower in colon and thymus (UniProt) | |
| Isoform / epitope | No annotated isoforms or processing; one 1–202 chain (UniProt) |
Section 1
Recommended ASF1B IHC & IF Protocols
The catalog antibody protocol (datasheet A05211) is accompanied by a published ASF1B IHC protocol for mouse tumor sections (PMC9782623).
| Sample | Paraffin-embedded human tonsil tissue; fixative not specified (datasheet A05211) |
| Fixation | Image fixative and duration unreported (datasheet A05211); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: Tris-EDTA pH 9.0 (datasheet A05211); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% normal serum of the secondary host, 30 min, room temperature (standard) |
| Primary antibody | Rabbit anti-ASF1B, 1:100 - 1:300 (datasheet A05211) |
| Primary incubation | Overnight at 4 °C (standard) |
| Detection | HRP-polymer secondary, DAB chromogen 5–10 min (standard) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | ASF1B-positive staining in neuronal cells of cerebral cortex (HPA tissue IHC: Medium). HPA tissue profile: Nuclear expression in several tissues, including testis. No signal in the no-primary control. |
💡Decision noteStart with Tris-EDTA pH 9.0 heat retrieval (datasheet A05211); citrate pH 6.0 at 120 °C is the published alternative (PMC9782623).
Section 2
What Is the Expected ASF1B Staining Pattern?
ASF1B staining should be predominantly nuclear in IHC, especially in testis spermatogonia and glandular cells of the duodenum and small intestine (HPA tissue IHC: medium staining; reliability Enhanced). HPA reports medium consistency between staining and RNA data (HPA tissue IHC). ASF1B is also annotated in the cytosol and has no transmembrane segment, so limited cytoplasmic signal is biologically plausible (UniProt Q9NVP2: subcellular location and topology).
| Nuclear staining in testis spermatogonia, with nuclei distinguishable from the counterstain (HPA tissue IHC). | This matches the reported ASF1B pattern: HPA scores spermatogonial staining as Medium and describes nuclear expression in several tissues, including testis (HPA tissue IHC). Judge the signal by its location and cell type; the HPA score does not require every cell on the section to stain. |
| Predominantly cytoplasmic staining with little nuclear contrast in a known-positive section. | Recheck the result because HPA describes nuclear tissue staining and nucleoplasmic ICC-IF localization (HPA tissue IHC; HPA subcellular). Cytosolic ASF1B is annotated, so cytoplasmic signal alone does not prove an artefact (UniProt Q9NVP2). Compare with a no-primary control and the nuclear pattern in the same tissue (general IHC practice). |
| Strong staining in adipocytes while the expected positive cells are faint. | Consider nonspecific antibody binding or endogenous chromogenic activity: HPA reports ASF1B as Not detected in adipocytes, but Medium in testis spermatogonia (HPA tissue IHC). A negative tissue result is a comparison point, not proof that every stained adipocyte is cross-reactivity; inspect controls and staining location (general IHC practice). |
| A diffuse deposit covers nuclei and surrounding tissue, obscuring cell boundaries. | The slide cannot reliably show the reported nuclear pattern (HPA tissue IHC). Check whether a no-primary section also develops color, then review blocking, washes and chromogen development for background (general IHC practice). Do not score diffuse deposit as ASF1B-positive cells. |
| No nuclear signal is visible in testis spermatogonia. | This conflicts with the Medium staining reported for that cell type (HPA tissue IHC). First check that the spermatogonia are identifiable and the staining run worked; then review antibody application, retrieval and detection using routine IHC controls (general IHC practice). A single blank section cannot establish biological absence. |
💡Expected ASF1B appearanceCall an IHC result positive when identifiable testis spermatogonia show discernible, predominantly nuclear staining around the HPA Medium category; diffuse color or strong staining of HPA-negative adipocytes is suspect (HPA tissue IHC; general IHC practice).
| Tissue and cell selection | Testis spermatogonia and duodenal or small-intestinal glandular cells are reported at Medium staining; colon glandular cells are Low, and adipocytes are Not detected (HPA tissue IHC). Compare like cell populations when judging a weak or absent result. |
| Antibody evidence | HPA lists IHC validation as Enhanced for HPA069385, while HPA054036 has no listed IHC status and has Supported ICC status (HPA antibodies). The tissue profile has Enhanced reliability with medium staining-to-RNA consistency (HPA tissue IHC); neither label validates an untested antibody. |
| IF/ICC Q: Where should fluorescence appear? | A: HPA reports enhanced nucleoplasmic localization in ICC-IF (HPA subcellular). This supports a nuclear localization check, while the IHC tissue profile supplies the cell-type comparisons for this paraffin-section guide (HPA tissue IHC). |
| Situation | Likely cause | Next action |
|---|---|---|
| Known-positive testis has no visible nuclear staining. | The run may have failed, or the intended cells may be missed; HPA reports Medium staining in spermatogonia (HPA tissue IHC). | Verify cell identity and run controls, then review the applied antibody, retrieval and detection steps (general IHC practice). |
| Only weak staining appears in colon glandular cells. | Low staining is reported for that population, so a faint result can fit the reference profile (HPA tissue IHC). | Compare with testis spermatogonia or small-intestinal glandular cells reported at Medium, using the same run (HPA tissue IHC; general IHC practice). |
| Cytoplasmic color dominates with little nuclear detail. | HPA reports nuclear tissue staining, although UniProt also annotates cytosolic ASF1B (HPA tissue IHC; UniProt Q9NVP2). | Compare nuclear contrast and a no-primary control before calling the cytoplasmic signal specific (general IHC practice). |
| Background persists across multiple tissue regions. | Nonspecific binding or detection background can obscure a nuclear readout (general IHC practice). | Inspect a no-primary section; review blocking, washing and chromogen development against the run controls (general IHC practice). |
| Adipocytes stain as strongly as the expected positive cells. | That conflicts with HPA's Not detected adipocyte result and may reflect cross-reactivity or endogenous activity (HPA tissue IHC; general IHC practice). | Check the no-primary control, staining compartment and antibody specificity before assigning ASF1B positivity (general IHC practice). |
| Two antibodies give different IHC patterns. | Their listed validation differs: HPA069385 is IHC Enhanced; HPA054036 has no listed IHC status (HPA antibodies). | Compare each result with the HPA nuclear tissue pattern and appropriate run controls; do not transfer ICC validation to IHC (HPA tissue IHC; HPA antibodies; general IHC practice). |
Experiment evidence
IHC & IF images showing ASF1B staining
A05211 · IHCImmunohistochemical analysis of paraffin-embedded human tonsil. 1, Antibody was diluted at 1:200(4° overnight). 2, Tris-EDTA,pH9.0 was used
A05211-2 · IFIF analysis of ASF1B using anti-ASF1B antibody (A05211-2). ASF1B was detected in an immunocytochemical section of MCF-7 cells. Enzyme antige
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000105011-ASF1B/tissue/cerebral+cortex#imid_20621171
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000105011-ASF1B/tissue/colon#imid_20621097
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000105011-ASF1B/tissue/liver#imid_20621098
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000105011-ASF1B/tissue/kidney#imid_20621099
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA054036; green = ASF1B, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA054036; green = ASF1B, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for ASF1B IHC & IF
🧪Run small intestine first and look for staining in its glandular cells (HPA: Medium in small-intestine glandular cells); use adipose tissue adipocytes as the negative comparator (HPA: Not detected in adipocytes). On the positive slide, use adjacent non-glandular cells as internal background comparators only if they show counterstain without specific signal; HPA does not establish those cells as ASF1B-negative (HPA: small-intestine glandular cells Medium).
Positive control tissue: Cerebral cortex (Neuronal cells, HPA Medium)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show ASF1B in A-431, HeLa, U2OS, KOLF2.1J, NIH 3T3, with annotated localisation: Nucleoplasm (enhanced) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control and an immunoglobulin control matched to the primary antibody’s host species and class, including monoclonal isotype when applicable; use ASF1B knockout material as a biological negative (standard IHC practice). For chromogenic detection in small intestine, quench endogenous peroxidase and, if using avidin–biotin detection, check endogenous biotin with the appropriate control (standard IHC practice).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected A05211 paraffin tonsil IHC caption does not report a fixative (selected-SKU caption: fixative not stated). That caption uses Tris-EDTA pH 9.0 retrieval and a 1:200 primary antibody dilution, but does not establish that retrieval is required for small intestine (selected-SKU caption: tonsil IHC). IF/ICC is feasible to assess nucleoplasmic staining in the listed image-bearing cell lines, but ease relative to paraffin IHC is unreported; in small intestine, distinguish cellular signal from luminal material and endogenous detection background (HPA: Nucleoplasm enhanced; HPA: small-intestine glandular cells Medium; standard IHC practice).
HPA tissue IHC evidence for ASF1B
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 |
|---|---|---|---|---|
| Cerebral cortex | Neuronal cells | Medium | Protein (IHC) | HPA → |
| Duodenum | Glandular cells | Medium | Protein (IHC) | HPA → |
| Epididymis | Glandular cells | Medium | Protein (IHC) | HPA → |
| Oral mucosa | Squamous epithelial cells | Medium | Protein (IHC) | HPA → |
| Small intestine | Glandular cells | Medium | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Bone marrow | Hematopoietic cells | Not detected | Protein (IHC) | HPA → |
| Bronchus | Respiratory epithelial cells | Not detected | Protein (IHC) | HPA → |
| Caudate | Glial cells | Not detected | Protein (IHC) | HPA → |
| Cerebellum | Cells in granular layer | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced ASF1B IHC Tips
Troubleshoot ASF1B staining by assessing nuclear signal, tissue context and controls alongside the catalog antibody’s paraffin-section IHC conditions.
How should I adjust retrieval when ASF1B nuclear staining is weak?
Start with heat-mediated Tris-EDTA retrieval at pH 9.0 (datasheet A05211). The catalog antibody’s paraffin-section image used this buffer with primary antibody at 1:200 overnight at 4°C (caption A05211). If nuclear staining remains weak, compare retrieval duration on adjacent sections while holding detection conditions constant; excessive heating can damage morphology (standard IHC practice). Include a section with an expected nuclear signal, such as testis with spermatogonial staining (HPA tissue IHC), and assess nuclei against the counterstain. If a different retrieval buffer is tested as a fallback, record it as an optimization rather than an established ASF1B condition (datasheet A05211).
Can fixation explain absent ASF1B staining in paraffin sections?
Target-specific sensitivity to fixation is unknown because the selected paraffin-section caption does not report a fixative (caption A05211). Record the specimen’s actual fixative, fixation duration and processing history before changing retrieval or antibody concentration (standard IHC practice). Compare similarly processed sections, then assess whether nuclear detail, counterstain quality and staining of an independent control antigen indicate a broader processing problem (standard IHC practice). For ASF1B, use the reported Tris-EDTA pH 9.0 retrieval as the starting condition (datasheet A05211). Do not assign a fixation effect to ASF1B solely because one tissue stains differently from another; its reported expression varies by tissue and cell type (HPA tissue IHC).
Should cytoplasmic ASF1B staining count as a positive IHC result?
Score nuclear staining separately because tissue IHC reports nuclear expression in several tissues (HPA tissue IHC). ASF1B is also annotated in the cytosol (UniProt Q9NVP2), so a cytoplasmic pattern warrants evaluation rather than automatic rejection. Examine whether the signal is confined to intact cells, survives an appropriate staining control and differs from diffuse background (standard IHC practice). In testis, assess spermatogonia specifically, where medium staining is reported, and use the nuclear counterstain to confirm compartment boundaries (HPA tissue IHC). Report nuclear and cytoplasmic results independently, including the affected cell population, because a single combined score can obscure the expected nuclear pattern (HPA tissue IHC).
What epitope issues matter when comparing ASF1B IHC antibodies?
The supplied record lists a 202-amino-acid ASF1B chain and no annotated isoforms, but it does not identify this antibody’s epitope (UniProt Q9NVP2; caption A05211). Confirm each antibody’s immunogen or mapped epitope before interpreting differences in paraffin-section staining (standard IHC practice). ASF1B has a reported phosphorylation site at Ser198 and histone H3 interaction through its C-terminus; neither establishes whether this antibody recognizes a modified or masked epitope (UniProt Q9NVP2). Compare antibodies under their own documented retrieval conditions and score the same cellular compartments on adjacent sections (standard IHC practice). If results disagree, use an independent specificity control before attributing the difference to an isoform or modification (standard IHC practice).
How can IF clarify an ambiguous ASF1B IHC pattern?
Use IF as a complementary localisation check for a chromogenic IHC finding, with a nuclear counterstain and a marker identifying the cell population being assessed (standard IF practice). For testis, a marker that identifies spermatogonia helps assess cells reported to show ASF1B staining (HPA tissue IHC). Choose a fluorophore channel with low tissue autofluorescence and include a no-primary control to identify background (standard IF practice). ASF1B has no transmembrane segment and is annotated in the nucleus and cytosol, so permeabilise cells or sections to access intracellular epitopes while optimizing the treatment for the antibody (UniProt Q9NVP2; standard IF practice). Interpret IF alongside IHC, since IF staining conditions are not specified in the selected catalog IHC caption (caption A05211).
How do I reduce diffuse or misleading ASF1B chromogenic staining?
First distinguish diffuse stain from discrete nuclear signal, the predominant tissue pattern reported for ASF1B (HPA tissue IHC). On adjacent sections, inspect a no-primary control and check whether staining follows tissue edges, folds or damaged areas (standard IHC practice). Apply a peroxidase block when using peroxidase-based chromogenic detection, and optimize protein blocking and washing before increasing primary antibody concentration (standard IHC practice). The catalog image used primary antibody at 1:200 overnight at 4°C and secondary antibody at 1:200 for 45 minutes at room temperature; treat these as documented starting conditions (caption A05211). Compare background with expected nuclear staining in the same staining run (HPA tissue IHC; standard IHC practice).
How should ASF1B IHC staining be quantified across specimens? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and nuclear compartment before scoring, since ASF1B tissue IHC is predominantly nuclear and varies across cell types (HPA tissue IHC). For each specimen, report the percentage of positive nuclei and, when intensity is reproducible, an H-score calculated from the proportions at each intensity level (standard IHC practice). If spatial abundance matters, report positive nuclei per mm² of viable tissue and normalize counts to the number of eligible cells or assessed tissue area (standard IHC practice). Apply the same positivity threshold, counterstain review and exclusion rules to every section (standard IHC practice). Keep cytoplasmic staining as a separate measure because ASF1B also has a cytosolic annotation (UniProt Q9NVP2).
When is an ASF1B IHC signal likely to be genuine?
A credible result shows staining in intact cells with interpretable nuclear boundaries, consistent with the reported nuclear tissue pattern (HPA tissue IHC; standard IHC practice). Medium spermatogonial staining in testis offers a documented cell-specific comparison, while adipocytes in adipose tissue are reported as not detected (HPA tissue IHC). Review unexpected strong staining in an unreported compartment or cell population against controls before calling it ASF1B (HPA tissue IHC; standard IHC practice). Exclude signals confined to cut edges, folds or necrotic regions, and check whether a no-primary section reveals endogenous enzyme or detection background (standard IHC practice). Treat cytoplasmic signal cautiously: ASF1B is annotated in the cytosol, but the tissue IHC profile emphasizes nuclei (UniProt Q9NVP2; HPA tissue IHC).
Boster reagents
Best ASF1B / Histone chaperone ASF1B IHC Antibodies
Anti-ASF1B options include paraffin-section IHC in human tonsil (A05211 image caption) and IF/ICC in MCF-7 cells (A05211-2 image caption); catalog reactivity covers human, mouse and rat (A05211 catalog).
Real IHC data
Anti-Histone chaperone ASF1B ASF1B Antibody
Cat # A05211
Real IF data
Anti-ASF1B Antibody ®
Cat # A05211-2
A05211 will render with human tonsil paraffin-section IHC data (A05211 image caption); its listed reactivity is human, mouse and rat (A05211 catalog). A05211-2 will render with IF/ICC data from MCF-7 cells (A05211-2 image caption) and is listed as human-reactive (A05211-2 catalog).
Which to pick: Choose A05211 for tissue IHC: its own image shows paraffin-embedded human tonsil with Tris-EDTA retrieval at pH 9.0 and primary antibody at 1:200 overnight (A05211 image caption); the fixative is unreported (A05211 image caption). Choose A05211-2 for IF/ICC in human cells because its own image documents MCF-7 staining at 5 μg/mL (A05211-2 image caption) and IHC is absent from its application list (A05211-2 catalog). For mouse or rat samples, A05211 is the option with listed reactivity (A05211 catalog); both antibodies are polyclonal (catalog dilution data).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q9NVP2 (ASF1B_HUMAN, Histone chaperone ASF1B).
- Human Protein Atlas. ASF1B tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. ASF1B subcellular location (ICC-IF): Localized to the nucleoplasm..
- Human Protein Atlas. ASF1B antibody validation summary (2 antibodies).
- Anti-silencing function 1B knockdown suppresses the malignant phenotype of colorectal cancer by inactivating the phosphatidylinositol 3-kinase/AKT pathway. World journal of gastrointestinal oncology 2022 — PMC9782623.
- ASF1B promotes gastric cancer liver metastasis through inhibiting ZDHHC9/PCBP1/ SLC7A11 signaling axis mediated ferroptosis. NPJ precision oncology 2026 — PMC12905238.
- ASF1B promotes gastric cancer progression by modulating H2AC20 and activating PI3K/AKT and ERK1/2 pathways. Frontiers in pharmacology 2025 — PMC11876136.
- Bioinformatics Analysis and Experimental Validation of ASF1B in Breast Tumors. Cancer medicine 2025 — PMC12432416.
- PubMed PMID:11470414 — UniProt-cited evidence.
- PubMed PMID:12842904 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for ASF1B (Histone chaperone ASF1B). Expected localisation Nuclear staining in tissue IHC (HPA tissue IHC). Antigen retrieval: Tris-EDTA pH 9.0 HIER, heat-mediated (datasheet A05211). Validated IHC antibody: A05211 at 1:100 - 1:300 (the product's own IHC validation image is shown). Controls (HPA): positive Cerebral cortex (Neuronal cells); negative Adipose tissue. IHC workflow; specimen preparation unspecified. Protocol steps: 1. Sample: Paraffin-embedded human tonsil tissue; fixative not specified (datasheet A05211); 2. Fixation: Image fixative and duration unreported (datasheet A05211); 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: Tris-EDTA pH 9.0 (datasheet A05211); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% normal serum of the secondary host, 30 min , room temperature (standard); 8. Primary antibody: Rabbit anti-ASF1B, 1:100 - 1:300 (datasheet A05211); 9. Primary incubation: Overnight at 4 °C (standard). Watch for: Fixation: Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image A05211); Caveat: Antibody staining and RNA show medium consistency (HPA tissue IHC); Isoform / epitope: No annotated isoforms or processing; one 1–202 chain (UniProt); Regulation: Testis-high; lower in colon and thymus (UniProt). Evidence: UniProt Q9NVP2, HPA tissue IHC · Enhanced, HPA ICC-IF · nucleoplasm., Datasheet A05211, PMC9782623. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/ASF1B/immunohistochemistry-ihc-guide.