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HSF1 / Heat shock factor protein 1 · IHC design guide
Design Immunohistochemistry for HSF1
Plan HSF1 staining in paraffin sections around the general nuclear pattern seen in tissue IHC (HPA tissue IHC). This guide covers fixation, antibody use, and interpretation of stress related redistribution (UniProt).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
HSF1 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 | General nuclear tissue staining (HPA tissue IHC) | |
| Staining pattern | Nuclear staining in glandular and other tissue cells (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A00250) | |
| Positive control | Adrenal gland+4 more · see all | |
| Negative control | None in HPA (detected in all 45 tissues); use no-primary + isotype controls |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep fixation conditions consistent across sections. (standard IHC practice; not target-specific) | |
| Caveat | During recovery, HSF1 can shift toward cytoplasm (UniProt) | |
| Regulation | Heat shock forms nuclear HSF1 foci (UniProt) | |
| Isoform / epitope | 2 isoforms, Long and Short; epitope coverage unknown (UniProt) |
Section 1
Recommended HSF1 IHC & IF Protocols
The catalog antibody protocol and three published HSF1 IHC protocols cover AML bone marrow, archival tissue microarrays, and hepatocellular carcinoma (datasheet A00250; PMC9573868; PMC5356658; PMC4214332).
| Sample | Paraffin-embedded human esophageal squamous carcinoma tissue; fixative not specified (datasheet A00250) |
| Fixation | Image fixative and duration unreported (datasheet A00250); 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 A00250); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A00250) |
| Primary antibody | Rabbit anti-HSF1, 2 μg/ml (datasheet A00250) |
| Primary incubation | Overnight at 4 °C (datasheet A00250) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet A00250) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | HSF1-positive staining in glandular cells of adrenal gland (HPA tissue IHC: High). HPA tissue profile: General nuclear expression. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA pH 8.0 retrieval for the catalog antibody (datasheet A00250); optimize retrieval for other antibodies where the published method omits conditions (PMC9573868; PMC4214332).
Section 2
What Is the Expected HSF1 Staining Pattern?
HSF1 is mainly nuclear, with nucleoplasmic staining expected in many cell types; HPA reports general nuclear expression with Supported tissue IHC reliability (HPA tissue IHC; HPA subcellular). Strong staining is documented in breast glandular cells and bronchial respiratory epithelial cells (HPA tissue IHC). A cytoplasmic component can occur (UniProt Q00613 subcellular). HSF1 has no transmembrane segment (UniProt Q00613 topology).
| Nuclei stain in breast glandular cells or bronchial respiratory epithelial cells. | This fits HPA's High staining in those cells and general nuclear tissue pattern (HPA tissue IHC). Compare nuclei with the counterstain and assess the proportion and intensity of stained cells; intensity can vary across tissue compartments (general IHC practice). |
| Staining is confined to extracellular material or cell borders, with nuclei clear. | That distribution does not fit the reported nuclear pattern or HSF1's lack of a transmembrane segment (HPA tissue IHC; UniProt Q00613 topology). Check for precipitate, edge staining, or nonspecific detection before interpreting the deposit as HSF1 (general IHC practice). |
| A normally low-staining cell population appears uniformly strong. | HPA lists liver cholangiocytes, soft-tissue fibroblasts, and appendix glandular cells as Low, rather than absent (HPA tissue IHC). Strong signal there warrants a specificity check, including cross-reactivity and endogenous chromogenic activity; a Low designation alone cannot prove a false positive (general IHC practice). |
| Color covers nuclei, cytoplasm, and blank slide areas with little cellular definition. | A deposit extending beyond cells is inconsistent with HPA's general nuclear tissue pattern (HPA tissue IHC). Uneven reagent coverage, incomplete washing, or detection background can obscure a real nuclear signal; inspect a negative control alongside the stained section (general IHC practice). |
| No nuclear signal appears in a selected High-staining tissue. | A blank breast glandular or bronchial epithelial compartment conflicts with HPA's High observations (HPA tissue IHC). First check tissue preservation, antibody application, retrieval and detection with controls; one negative section does not establish that the tissue lacks HSF1 (general IHC practice). |
💡Expected HSF1 appearanceCall the stain positive when nuclei are clearly marked in HPA High cells such as breast glandular or bronchial respiratory epithelial cells; widespread acellular color or isolated border staining is suspect (HPA tissue IHC; UniProt Q00613 topology; general IHC practice).
| Tissue and cell selection | HPA reports High staining in several glandular and epithelial populations, including breast glandular cells and bronchial respiratory epithelial cells, and Low staining in liver cholangiocytes, soft-tissue fibroblasts, and appendix glandular cells (HPA tissue IHC). Use the identified cell population, rather than the whole organ, when judging a result. |
| Cellular location and stress state | HPA describes a mainly nucleoplasmic location with additional cytosolic signal (HPA subcellular). UniProt reports cytoplasmic monomers in unstressed cells, nuclear accumulation and nuclear stress bodies after heat shock, and cytoplasmic relocalization during recovery (UniProt Q00613 subcellular). Interpret a cytoplasmic component in its experimental context. |
| Catalog antibody validation | HPA lists HPA008888 and CAB004239 as Supported for IHC; HPA008888 is also Supported for ICC (HPA antibodies). Supported tissue reliability reflects agreement between antibody staining and RNA expression data (HPA tissue IHC). These designations support use of controls but do not guarantee specificity in every specimen. |
| Isoforms and processing | UniProt lists Long and Short isoforms, one chain spanning residues 1–529, and no signal peptide or propeptide (UniProt Q00613 isoforms; processing). The supplied record gives no antibody epitope, so it cannot establish whether either catalog antibody recognizes both isoforms or whether an isoform changes the observed stain. |
| Fixation and antigen retrieval | Target-specific fixation sensitivity and retrieval requirements are unreported in the supplied UniProt and HPA records. For paraffin-section IHC, optimize retrieval against a positive control and check the resulting nuclear pattern; do not infer an HSF1-specific fixation effect from its topology or HPA staining levels (general IHC practice). |
| IF/ICC Q&A: what location should appear? | Expect mainly nucleoplasmic fluorescence, with possible cytosolic signal (HPA subcellular). HPA008888 has Supported ICC validation, and HPA shows ICC/IF images in A-431, U-251MG, U2OS, and KOLF2.1J cells (HPA antibodies; HPA subcellular). IF/ICC staining conditions belong in the separate guide. |
| Situation | Likely cause | Next action |
|---|---|---|
| The positive-control nuclei are blank. | The run may have lost signal during retrieval, antibody application, or chromogenic detection; the supplied sources do not identify an HSF1-specific fixation failure (general IHC practice). | Repeat with a documented High cell population, such as breast glandular cells, and inspect retrieval and detection controls before changing the biological interpretation (HPA tissue IHC; general IHC practice). |
| Strong color appears mainly at tissue edges or in empty areas. | An acellular or edge-weighted deposit is inconsistent with HPA's general nuclear pattern and may reflect uneven reagent coverage or chromogen deposit (HPA tissue IHC; general IHC practice). | Compare an adjacent negative control, check section coverage and washing, and score only cell-associated staining with interpretable nuclei (general IHC practice). |
| The negative control is brown. | Residual endogenous detection activity or nonspecific secondary/detection binding can create chromogenic signal independently of the primary antibody (general IHC practice). | Verify the control setup and appropriate activity blocking, then repeat detection before assigning any brown deposit to HSF1 (general IHC practice). |
| Only cytoplasmic signal is visible. | Cytosolic HSF1 is reported, and UniProt describes state-dependent movement, but HPA tissue IHC reports general nuclear expression (HPA subcellular; HPA tissue IHC; UniProt Q00613 subcellular). A cytoplasmic-only section therefore needs context and validation. | Check nuclear counterstain and a High-staining control, review the stress or recovery condition, and confirm that detection is not broadly cytoplasmic in the negative control (HPA tissue IHC; UniProt Q00613 subcellular; general IHC practice). |
| A Low HPA cell population stains more strongly than the control tissue. | HPA's Low category is an observed level, not proof of absence; unexpected strength can also arise from cross-reactivity or detection background (HPA tissue IHC; general IHC practice). | Confirm the exact cell identity, compare a negative control and a documented High population in the same run, and avoid calling the result specific from intensity alone (HPA tissue IHC; general IHC practice). |
| Adjacent sections give inconsistent nuclear intensity. | Uneven section handling or assay coverage can change apparent intensity across a run; the supplied sources provide no target-specific fixation-effect evidence (general IHC practice). | Review section quality, reagent coverage, retrieval consistency, and control performance; compare equivalent cell populations before interpreting a biological difference (general IHC practice). |
Experiment evidence
IHC & IF images showing HSF1 staining
A00250 · IHCIHC analysis of HSF1 using anti-HSF1 antibody (A00250). HSF1 was detected in a paraffin-embedded section of human esophageal squamous carcin
A00250 · IHCIHC analysis of HSF1 using anti-HSF1 antibody (A00250). HSF1 was detected in a paraffin-embedded section of human lung cancer tissue. Heat m
M00250-1 · IHCIHC analysis of HSF1 using anti-HSF1 antibody (M00250-1). HSF1 was detected in a paraffin-embedded section of human bladder cancer tissue. H
M00250-1 · IHCIHC analysis of HSF1 using anti-HSF1 antibody (M00250-1). HSF1 was detected in a paraffin-embedded section of human breast cancer tissue. He
P00250 · IHCIHC analysis of HSF1 using anti-HSF1 antibody (P00250). HSF1 was detected in a paraffin-embedded section of human breast cancer tissue. Heat
P00250 · IHCIHC analysis of HSF1 using anti-HSF1 antibody (P00250). HSF1 was detected in a paraffin-embedded section of human spleen tissue. Heat mediat
P00250 · IFImmunofluorescent analysis using the Antibody at 1:50 dilution.
A00250S326 · IFICC staining p-HSF1(S326) in Hela cells (green). The nuclear counter stain is DAPI (blue). Cells were fixed in paraformaldehyde, permeabilis
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000185122-HSF1/tissue/cerebral+cortex#imid_1437044
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000185122-HSF1/tissue/colon#imid_1436978
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000185122-HSF1/tissue/liver#imid_1436963
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000185122-HSF1/tissue/kidney#imid_1436964
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA008888; green = HSF1, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA008888; green = HSF1, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for HSF1 IHC & IF
🧪Run breast first and score its glandular cells for HSF1 staining (HPA: High in breast glandular cells). HPA detects HSF1 in all 45 scored tissues, so there is no supported negative tissue; use no-primary and isotype controls, and do not assume that any unstained cells on the breast slide are true internal negatives (HPA: no negative tissues).
Positive control tissue: Adrenal gland (Glandular cells, HPA High)
Negative control tissue: None in HPA: HSF1 is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead.
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show HSF1 in A-431, U-251MG, U2OS, KOLF2.1J, with annotated localisation: Nucleoplasm (supported) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only section and a concentration-matched rabbit IgG isotype control matched to the primary antibody’s clonality; use HSF1 knockout material as a biological specificity control if available (caption: rabbit anti-HSF1; standard IHC control practice). Check endogenous peroxidase activity in the breast section before interpreting brown DAB signal, particularly around blood or inflammatory cells (caption: HRP/DAB detection; standard IHC practice).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected A00250 paraffin-section caption does not state a fixative (A00250 tissue-IHC caption). That caption documents heat-mediated retrieval in EDTA at pH 8.0, but does not establish whether retrieval is required for every specimen (A00250 tissue-IHC caption). The supplied evidence does not establish that frozen sections or IF are easier than paraffin IHC; blood-associated peroxidase in breast sections can complicate DAB interpretation (A00250 tissue-IHC caption; standard IHC practice).
HPA tissue IHC evidence for HSF1
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Supported — High 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 |
|---|---|---|---|---|
| Adrenal gland | Glandular cells | High | Protein (IHC) | HPA → |
| Breast | Glandular cells | High | Protein (IHC) | HPA → |
| Bronchus | Respiratory epithelial cells | High | Protein (IHC) | HPA → |
| Cerebellum | Cells in molecular layer | High | Protein (IHC) | HPA → |
| Cerebral cortex | Neuronal cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| None in HPA: HSF1 is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead. | ||||
Section 3
Advanced HSF1 IHC Tips
Troubleshoot HSF1 staining by checking retrieval, nuclear localisation, controls, and scoring in paraffin section IHC; use the IF guidance for companion imaging.
What retrieval should I try first when HSF1 staining is weak?
Start with heat-mediated antigen retrieval in EDTA at pH 8.0 for paraffin sections (datasheet A00250). The selected HSF1 image used this retrieval before 10% goat serum blocking and 2 μg/ml primary antibody overnight at 4°C (datasheet A00250). If staining is weak, compare heating intervals on matched sections while holding the antibody and detection steps constant; inspect tissue integrity because excessive heating can damage sections (standard IHC practice). Compare nuclear signal with a reference section and a no-primary control before changing buffer chemistry, since general nuclear expression is the expected tissue pattern (HPA: general nuclear expression; standard IHC practice).
Could fixation explain inconsistent HSF1 nuclear staining?
HSF1-specific fixation sensitivity in paraffin IHC is unknown because the selected tissue caption does not report a fixative (datasheet A00250). Record fixative identity, fixation duration, and processing history for each block, then compare adjacent sections under the same EDTA pH 8.0 retrieval and detection conditions (standard IHC practice; datasheet A00250). Include a reference section processed alongside each run and a no-primary control to help separate sample handling from nonspecific staining (standard IHC practice). Neither the HPA nuclear pattern nor HSF1 localisation and modification annotations establish formalin compatibility or an optimal fixation time for this antibody (HPA: general nuclear expression; UniProt Q00613; datasheet A00250).
How should I assess cytoplasmic versus nuclear HSF1 staining?
Score nuclear and cytoplasmic chromogen separately rather than treating all brown staining as equivalent, because HPA describes mainly nucleoplasmic HSF1 with additional cytosolic localisation (HPA: subcellular localisation). UniProt also describes nucleocytoplasmic shuttling, cytoplasmic monomers in unstressed cells, and nuclear stress bodies after heat shock (UniProt Q00613). Compare intact cells across the section at the same magnification and check whether nuclear staining is distinct from haematoxylin and diffuse chromogen haze (standard IHC practice). Record stress or treatment history when available, but do not assign activation from localisation alone: transcriptional activity depends on trimerisation and other regulation (UniProt Q00613).
Can this antibody distinguish HSF1 isoforms or modification states in tissue?
Do not assign the Long or Short isoform from a positive paraffin section: the record lists 2 isoforms, while the supplied tissue caption does not define an isoform-specific epitope (UniProt Q00613; datasheet A00250). HSF1 has annotated modifications, including phosphorylation at Ser-121, but staining with this antibody does not establish phosphorylation state without a validated modification-specific epitope (UniProt Q00613; datasheet A00250). If an immunogen sequence becomes available, map it against both isoforms before making an isoform claim (standard IHC practice). For uncertain staining, compare localisation and tissue pattern with an independently validated antibody or orthogonal expression evidence while keeping retrieval conditions matched (standard IHC practice; HPA: supported tissue staining).
How can companion IF help resolve ambiguous HSF1 IHC localisation?
Use IF as a companion localisation check, while interpreting this page’s chromogenic paraffin staining with the catalog antibody’s documented IHC conditions (datasheet A00250). Multiplex HSF1 with a validated marker of the expected cell type so nuclear signal can be assigned to the appropriate cells; HPA reports high staining in several glandular and epithelial populations (HPA: tissue IHC; standard IF practice). Choose spectrally separated fluorophores, favouring a far-red channel if tissue autofluorescence obscures shorter wavelengths, and include single-colour controls (standard IF practice). Because HSF1 is nucleoplasmic and cytosolic with no transmembrane segment, use an IF permeabilisation condition that permits access to intracellular epitopes, then compare nuclear and cytosolic signal (HPA: subcellular localisation; UniProt Q00613; standard IF practice).
What should I change when brown background obscures HSF1 nuclei?
First inspect a no-primary section and the distribution of brown signal to distinguish detection background from specific nuclear staining (standard IHC practice; HPA: general nuclear expression). In a peroxidase and DAB workflow, block endogenous peroxidase, optimise blocking and washes, and check whether chromogen development is excessive (standard IHC practice; datasheet A00250: peroxidase and DAB detection). The selected image used 10% goat serum blocking and 2 μg/ml primary antibody overnight at 4°C; treat these as documented starting conditions for A00250 (datasheet A00250). If background persists, titrate primary antibody on matched sections while preserving EDTA pH 8.0 retrieval and an appropriate positive reference (datasheet A00250; standard IHC practice).
How should I quantify heterogeneous HSF1 staining across a section? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and regions before scoring, and exclude folded, detached, or necrotic areas using the counterstained section (standard IHC practice). For nuclear HSF1, report percentage of positive nuclei and an H-score calculated from intensity grades 0–3 and their percentages, giving a range of 0–300 (standard IHC practice; HPA: general nuclear expression). If cell abundance varies, normalise positive counts to total evaluable nuclei of the same cell population, or report positive cells per mm² of viable tissue (standard IHC practice). Keep retrieval, antibody concentration, chromogen development, thresholds, and reference sections consistent across comparisons (standard IHC practice; datasheet A00250: EDTA pH 8.0 retrieval).
How do I distinguish true HSF1 signal from tissue artefact?
A convincing positive pattern should include staining in intact nuclei, consistent with the reported general nuclear and mainly nucleoplasmic expression of HSF1 (HPA: tissue IHC and subcellular localisation). Cytoplasmic signal can be plausible because HSF1 shuttles between compartments, but isolated diffuse cytoplasmic brown staining needs comparison with nuclear signal and controls (UniProt Q00613; standard IHC practice). Distrust signal confined to tissue edges or necrotic regions, and check a no-primary section for endogenous enzyme or detection background in the peroxidase and DAB workflow (standard IHC practice; datasheet A00250: detection method). Judge the relevant cell population against morphology and a reference section; localisation alone cannot establish HSF1 transcriptional activation (standard IHC practice; UniProt Q00613).
Boster reagents
Best HSF1 / Heat shock factor protein 1 IHC Antibodies
Human paraffin-section IHC images show HSF1 staining in esophageal squamous carcinoma, bladder cancer and breast cancer; an ICC image shows HeLa cells (catalog image captions).
Real IHC data
Anti-HSF1 Antibody ®
Cat # A00250
Real IHC data
Anti-HSF1 Rabbit Monoclonal Antibody
Cat # M00250-1
Real IHC data
Anti-Phospho-HSF1 (S326) Rabbit Monoclonal Antibody
Cat # P00250
Real IF data
Anti-HSF1 (Phospho-S326) Antibody
Cat # A00250S326
A00250 has a human esophageal squamous carcinoma IHC image, and M00250-1 has a human bladder cancer IHC image (respective image captions). P00250 has a human breast cancer IHC image, while A00250S326 has a phospho-HSF1(S326) ICC image in HeLa cells (respective image captions).
Which to pick: For human paraffin-section IHC, select A00250 for esophageal squamous carcinoma, rabbit monoclonal M00250-1 for bladder cancer, or rabbit monoclonal P00250 for phospho-HSF1(S326) in breast cancer (catalog titles and respective IHC image captions); the IHC captions do not report a fixative. For IF/ICC, M00250-1 and P00250 list both applications, and A00250S326 has an ICC image from paraformaldehyde-fixed HeLa cells (catalog applications; A00250S326 image caption). None has documented reactivity beyond human for cross-species selection (catalog reactivity: all four SKUs).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q00613 (HSF1_HUMAN, Heat shock factor protein 1).
- Human Protein Atlas. HSF1 tissue IHC expression (reliability: Supported).
- Human Protein Atlas. HSF1 subcellular location (ICC-IF): Mainly localized to the nucleoplasm. In addition localized to the cytosol..
- Human Protein Atlas. HSF1 antibody validation summary (2 antibodies).
- HSF1 is a driver of leukemia stem cell self-renewal in acute myeloid leukemia. Nature communications 2022 — PMC9573868.
- Heat Shock Factor 1 Predicts Poor Prognosis of Gastric Cancer. Yonsei medical journal 2018 — PMC6192884.
- Upregulation of HSF1 in estrogen receptor positive breast cancer. Oncotarget 2016 — PMC5356658.
- Upregulation of heat shock factor 1 transcription activity is associated with hepatocellular carcinoma progression. Molecular medicine reports 2014 — PMC4214332.
- PubMed PMID:1871105 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
- PubMed PMID:16421571 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for HSF1 (Heat shock factor protein 1). Expected localisation General nuclear tissue staining (HPA tissue IHC). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A00250). Validated IHC antibody: A00250 at 2 μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Adrenal gland (Glandular cells); negative None in HPA (detected in all 45 tissues); use no-primary + isotype controls. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human esophageal squamous carcinoma tissue; fixative not specified (datasheet A00250); 2. Fixation: Image fixative and duration unreported (datasheet A00250); 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 A00250); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A00250); 8. Primary antibody: Rabbit anti-HSF1, 2 μg/ml (datasheet A00250); 9. Primary incubation: Overnight at 4 °C (datasheet A00250). Watch for: Fixation: Keep fixation conditions consistent across sections. (standard IHC practice; not target-specific); Caveat: During recovery, HSF1 can shift toward cytoplasm (UniProt); Isoform / epitope: 2 isoforms, Long and Short; epitope coverage unknown (UniProt); Regulation: Heat shock forms nuclear HSF1 foci (UniProt). Evidence: UniProt Q00613, HPA tissue IHC · Supported, HPA ICC-IF · Mainly localized to the nucleoplasm. In addition localized to the…, Datasheet A00250, PMC9573868, PMC5356658. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/HSF1/immunohistochemistry-ihc-guide.