This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
ARNT / Aryl hydrocarbon receptor nuclear translocator · IHC design guide
Design Immunohistochemistry for ARNT
Plan chromogenic ARNT IHC on paraffin sections using 1:50 as the catalog antibody’s starting dilution (datasheet M02263). Assess nuclear staining against the high signal reported in fallopian tube glandular cells (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
ARNT 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 most tissues (HPA tissue IHC) | |
| Staining pattern | Nuclear staining across most tissue cell types (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet M02263) | |
| Positive control | Endometrium+4 more · see all | |
| Negative control | Cerebellum+1 more · see all |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep fixation consistent across paraffin sections. (standard IHC practice; not target-specific) | |
| Caveat | Staining and RNA show medium consistency (HPA tissue IHC) | |
| Regulation | Expression regulation is unreported (UniProt) | |
| Isoform / epitope | 4 isoforms; epitope coverage is unspecified (UniProt) |
Section 1
Recommended ARNT IHC & IF Protocols
The catalog antibody's IHC-P protocol (datasheet M02263) is followed by four published ARNT IHC protocols (PMC2938742; PMC7418509; PMC4484474; PMC11133443).
| Sample | Paraffin-embedded human renal cancer tissue; fixative not specified (datasheet M02263) |
| Fixation | Image fixative and duration unreported (datasheet M02263); 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 M02263); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet M02263) |
| Primary antibody | Rabbit monoclonal (clone EAD-1) anti-ARNT, 1:50 (datasheet M02263) |
| Primary incubation | Overnight at 4 °C (datasheet M02263) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet M02263) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | ARNT-positive staining in cells in endometrial stroma of endometrium (HPA tissue IHC: Medium). 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 M02263); published alternatives use citrate pH 6.0 (PMC2938742; PMC4484474).
Section 2
What Is the Expected ARNT Staining Pattern?
ARNT is a nuclear transcription factor with no transmembrane segment (UniProt P27540). Expect nuclear IHC staining in many tissues, including fallopian tube glandular cells, lung alveolar type I cells and placental decidual cells (HPA: High in each). HPA describes nuclear expression in most tissues, with Supported reliability and medium consistency between antibody staining and RNA expression (HPA: tissue IHC). Interpret each cell population against its reported pattern.
| Clear nuclear chromogen in fallopian tube glandular cells, lung alveolar type I cells or placental decidual cells. | This matches HPA's High staining in those populations and UniProt's nuclear localization (HPA: tissue IHC; UniProt P27540). Judge the proportion and intensity within the named cell population; surrounding cells need their own reference pattern before being called positive. |
| Predominantly cytoplasmic, membranous or extracellular signal with little nuclear signal. | This conflicts with the expected compartment (UniProt P27540: nucleus; HPA: nuclear expression in most tissues). Check morphology and detection background before interpreting it as ARNT. The record has no transmembrane segment or signal peptide to support a membrane or secreted pattern (UniProt P27540). |
| Strong staining in a cell population reported as not detected, such as cerebellar granular layer cells or cardiomyocytes. | Treat this as unexpected, then review tissue identification and controls (HPA: Not detected in those populations). Cross-reactivity or endogenous chromogenic activity are possible assay explanations (general IHC practice); one unexpected field alone does not establish either cause. |
| Diffuse chromogen across tissue, including acellular areas, obscures nuclear boundaries. | This is background rather than a scorable nuclear pattern (general IHC practice; UniProt P27540: nucleus). Compare a control lacking primary antibody, then assess blocking, washing and detection conditions (general IHC practice). Background cannot be assigned to ARNT from color alone. |
| No nuclear signal in a high-staining reference population. | An absent result warrants an assay check when the named cells are present: HPA reports High staining in fallopian tube glandular, lung alveolar type I and placental decidual cells (HPA: tissue IHC). HPA's Supported reliability and medium RNA agreement make these useful references, not guarantees for every section (HPA: tissue IHC). |
💡Expected ARNT appearanceCall positive a resolved nuclear signal in the relevant cells, potentially strong in HPA High populations; diffuse cytoplasmic, membranous or acellular color is suspect (HPA: tissue IHC; UniProt P27540: nucleus; general IHC practice).
| Reference cell population | HPA reports High staining in fallopian tube glandular cells, lung alveolar type I cells and placental decidual cells; endometrial stromal cells are Medium (HPA: tissue IHC). Select and score the specified cells, rather than treating an entire tissue as uniformly positive. |
| Low and undetected populations | Parathyroid glandular cells and bronchial respiratory epithelial cells are Low; cerebellar granular layer cells and cardiomyocytes are Not detected (HPA: tissue IHC). These labels describe those populations and do not certify every other cell in the section as negative. |
| Antibody evidence | HPA lists HPA001759 and CAB004318 as Supported for IHC; HPA001759 is also Supported for ICC (HPA: antibody validation). These ratings support use as references but do not identify an epitope, specify a working dilution or guarantee identical staining across preparations. |
| Isoforms and epitope scope | UniProt lists four ARNT isoforms and places bHLH, PAS and PAC domains within the protein (UniProt P27540). No antibody epitope is supplied here, so the record cannot establish which isoforms a particular IHC antibody recognizes or explain a discrepancy by epitope location. |
| IF/ICC Q&A: Where should ARNT appear? | In ICC-IF, expect nucleoplasm and nuclear bodies; both locations are supported by HPA images from A-431, U-251MG and U2OS (HPA: subcellular ICC-IF). This describes localization only; apply IF/ICC preparation and detection guidance from its own guide. |
| Fixation evidence | No target-specific fixation effect is reported in the supplied UniProt or HPA records. If results differ across preparations, document fixation and compare matched controls as general IHC practice; do not infer ARNT-specific epitope masking or sensitivity from HPA staining levels. |
| Situation | Likely cause | Next action |
|---|---|---|
| High-reference cells show no nuclear chromogen. | The target population may be missing, or the staining run may have failed (HPA: High reference populations; general IHC practice). | Confirm the named cells by morphology, then review the catalog antibody's IHC-P instructions and run controls; check retrieval, dilution and detection against that protocol (general IHC practice). Do not invent a target-specific retrieval condition. |
| Nuclear staining is weak in a reported High population. | Signal may be below the chosen scoring threshold, or the section may not contain the reported cells (HPA: tissue IHC; general IHC practice). | Compare the same cell type in a documented positive section processed alongside it. Review antibody dilution and development against the actual IHC-P protocol (general IHC practice); HPA's High category supplies no dilution or expected chromogen density. |
| Cytoplasmic color dominates over nuclear color. | This disagrees with ARNT's nuclear annotation; nonspecific staining or detection background is possible (UniProt P27540; general IHC practice). | Inspect nuclear boundaries and a no-primary control, then review blocking, washes and chromogen development (general IHC practice). Report unresolved localization as ambiguous instead of assigning cytoplasmic ARNT. |
| An HPA Not detected cell population stains strongly. | The cell may be misidentified, or signal may reflect cross-reactivity or endogenous detection activity (HPA: cerebellar granular layer cells and cardiomyocytes Not detected; general IHC practice). | Recheck the precise cell population; compare a no-primary control and, if available, another IHC-supported antibody (HPA: HPA001759 and CAB004318; general IHC practice). Avoid calling the whole tissue negative from a single population label. |
| Chromogen covers tissue broadly or appears outside cells. | Diffuse deposition obscures the nuclear compartment required for interpretation (UniProt P27540: nucleus; general IHC practice). | Use a no-primary control to assess detection background, then review blocking, washing and development time (general IHC practice). Score only distinguishable nuclei after background is adequately resolved. |
| Two sections give different staining after different fixation histories. | The supplied records do not establish an ARNT-specific fixation response (UniProt P27540; HPA: tissue IHC). | Record preparation histories and compare matched positive controls and the same named cell type under the documented IHC-P workflow (general IHC practice). Attribute the difference to fixation only if the comparison supports it. |
Experiment evidence
IHC & IF images showing ARNT staining
M02263 · IHCIHC analysis of ARNT using anti-ARNT antibody (M02263). ARNT was detected in a paraffin-embedded section of human renal cancer tissue. Heat
M02263 · IHCIHC analysis of ARNT using anti-ARNT antibody (M02263). ARNT was detected in a paraffin-embedded section of mouse ovary tissue. Heat mediate
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000143437-ARNT/tissue/cerebral+cortex#imid_1357292
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000143437-ARNT/tissue/colon#imid_1357218
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000143437-ARNT/tissue/liver#imid_1357227
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000143437-ARNT/tissue/kidney#imid_1357220
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA001759; green = ARNT, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA001759; green = ARNT, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for ARNT IHC & IF
🧪Run fallopian tube first; glandular cells should show nuclear ARNT staining (HPA: High in fallopian tube glandular cells; UniProt P27540: nucleus). Use cerebellum as the negative tissue, focusing on granular-layer cells (HPA: Not detected in cerebellum granular-layer cells); on the positive slide, nonglandular cells should lack strong nuclear signal, but they are a background reference rather than a validated ARNT-negative population (HPA: positive call is specific to glandular cells).
Positive control tissue: Endometrium (Cells in endometrial stroma, HPA Medium)
Negative control tissue: Cerebellum (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show ARNT in A-431, U-251MG, U2OS, with annotated localisation: Nucleoplasm (supported), Nuclear bodies (supported) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control and a rabbit IgG isotype control matched to the primary antibody’s clonality if known (selected M02263 caption: rabbit primary); confirm specificity with ARNT knockout material or peptide blocking if the immunizing peptide is available (standard IHC practice). Quench endogenous peroxidase and inspect blood or inflammatory cells for residual DAB signal in the fallopian tube section (standard chromogenic IHC practice).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected M02263 paraffin-section caption does not state a fixative (selected M02263 caption). The demonstrated IHC conditions use heat retrieval in EDTA at pH 8.0, a 1:50 primary dilution overnight at 4°C, and HRP/DAB detection; retrieval dependence has not been established by a comparison without retrieval (selected M02263 caption). The supplied evidence does not establish that frozen sections or IF are easier than paraffin IHC; fallopian tube DAB interpretation may be complicated by endogenous peroxidase in blood or inflammatory cells (standard IHC practice).
HPA tissue IHC evidence for ARNT
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Supported — 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 |
|---|---|---|---|---|
| Endometrium | Cells in endometrial stroma | Medium | Protein (IHC) | HPA → |
| Fallopian tube | Glandular cells | High | Protein (IHC) | HPA → |
| Lung | Alveolar cells type I | High | Protein (IHC) | HPA → |
| Placenta | Decidual cells | High | Protein (IHC) | HPA → |
| Adipose tissue | Adipocytes | Medium | Protein (IHC) | HPA → |
Section 3
Advanced ARNT IHC Tips
Troubleshoot ARNT staining in paraffin sections by checking nuclear localisation, matched processing controls, and cell-specific scoring (UniProt P27540; HPA tissue IHC).
What should I change when ARNT nuclear staining is weak after retrieval?
Begin with heat-mediated retrieval in EDTA at pH 8.0 for paraffin sections (datasheet M02263). The selected renal cancer image used this condition with antibody at 1:50 overnight at 4°C (caption M02263), so establish that workflow as the reference condition. If nuclei remain weak, compare shorter and longer heating within the instrument’s recommended range, allow consistent cooling, and inspect tissue integrity before increasing primary concentration. Score nuclear signal rather than diffuse cytoplasmic colour because ARNT is nuclear (UniProt P27540 subcellular location), and include a section with expected nuclear expression in each retrieval run (HPA tissue IHC).
Could fixation explain inconsistent ARNT staining between paraffin blocks?
The selected paraffin-section image does not state its fixative (caption M02263), and ARNT-specific fixation sensitivity is unknown. For a prospective comparison, process matched pieces using a documented general fixation workflow, such as 10% neutral buffered formalin with recorded 6 and 24 hour intervals; treat those times as test conditions, not ARNT requirements. Hold section thickness, EDTA pH 8.0 retrieval, and detection constant during the comparison (datasheet M02263 retrieval). Compare nuclear staining only in preserved, viable cells, and record fixation history when interpreting differences, because tissue morphology and antigen accessibility can both change with processing.
How should I assess cytoplasmic or patchy ARNT staining?
Expect predominantly nuclear staining because ARNT is annotated to the nucleus (UniProt P27540 subcellular location), with nucleoplasmic and nuclear-body localisation supported by imaging (HPA subcellular). Examine a counterstained serial section or the same chromogenic section at high magnification to confirm that the coloured deposit lies within intact nuclear boundaries. Broad cytoplasmic colour without corresponding nuclear signal warrants checks of primary concentration, secondary-only background, and chromogen development; ARNT has no transmembrane segment (UniProt P27540 topology). Patchiness should be judged against tissue preservation and cell identity before assigning biological meaning, since the tissue profile describes nuclear expression across most tissues (HPA tissue IHC).
How can epitope choice affect interpretation of ARNT IHC?
ARNT has 4 annotated isoforms (UniProt P27540 isoforms), but the supplied M02263 caption does not identify the antibody epitope (caption M02263). Request the immunogen or mapped epitope and align it across isoforms before claiming that a stained nucleus represents every variant. Relevant annotated regions include bHLH residues 89–142, PAS regions 161–235 and 349–419, and a phosphoserine at 77 (UniProt P27540 domains and modified residues). If staining changes with processing, test retrieval and an independent epitope where available; do not attribute a difference to isoforms or phosphorylation without direct epitope and specificity evidence.
How should I follow up ARNT IHC with multiplex immunofluorescence?
For an IF follow-up, pair ARNT with a validated marker of the expected cell type, such as a marker for alveolar type I cells where ARNT staining is reported as high (HPA tissue IHC). Choose a far-red ARNT fluorophore when tissue autofluorescence is strong, and collect unstained and single-colour controls to set exposure and spectral separation. Because the expected signal is nucleoplasmic or in nuclear bodies (HPA subcellular), optimise gentle post-fixation permeabilisation for access across the plasma and nuclear membranes, for example testing 0.1% Triton X-100 for 5–10 minutes. Verify nuclear colocalisation with a DNA counterstain; the paraffin IHC caption supplies no IF fixation or dilution condition (caption M02263).
What controls help resolve diffuse brown staining around ARNT-positive nuclei?
Start with the documented 10% goat-serum block and 1:50 primary concentration as reference conditions for this antibody (caption M02263). In a standard chromogenic workflow, test a peroxidase block such as 3% hydrogen peroxide for 10 minutes, then compare primary-omission and secondary-only sections to locate nonspecific signal; these are general controls, not ARNT-specific evidence. Keep secondary incubation and DAB development consistent while troubleshooting; the selected image used a peroxidase-linked secondary for 30 minutes at 37°C and DAB (caption M02263). If brown colour persists outside nuclei, shorten development or titrate antibody while preserving interpretable nuclear staining (UniProt P27540 subcellular location).
What is a defensible way to quantify ARNT staining across sections? ⚠ ANSWER MARKED FOR VERIFICATION
Segment intact nuclei using the counterstain, then report the percentage of nuclear-positive cells and an intensity-based nuclear H-score from 0–300; nuclear localisation is expected for ARNT (UniProt P27540 subcellular location). Define positivity thresholds with matched negative controls and keep illumination, chromogen development, and scoring settings constant across batches. Normalise counts to viable nucleated cells in the same annotated compartment, or report positive nuclei per mm² alongside total nuclear density when cell abundance differs. Stratify by cell type rather than pooling a whole section, because HPA reports different cell-level staining intensities and only medium consistency between antibody staining and RNA data (HPA tissue IHC).
How do I distinguish genuine ARNT positivity from staining artefacts?
A credible positive is nuclear within an identifiable, viable cell (UniProt P27540 subcellular location), with staining in expected populations such as fallopian-tube glandular cells or lung alveolar type I cells (HPA tissue IHC). Treat isolated cytoplasmic colour, tissue-edge accentuation, necrotic deposits, and colour persisting in a primary-omission control as artefact candidates; check peroxidase blocking because DAB detection uses a peroxidase-linked system (caption M02263). Cells in the cerebellar granular layer and cardiomyocytes were reported as not detected, offering context rather than universal negative controls (HPA tissue IHC). Interpret deviations cautiously because the tissue staining reliability is Supported with medium RNA concordance (HPA tissue IHC).
Boster reagents
Best ARNT / Aryl hydrocarbon receptor nuclear translocator IHC Antibodies
M02263 has real ARNT IHC images from human renal cancer and mouse ovary paraffin sections (M02263 IHC captions); its listed reactivity is Human (catalog: M02263).
Real IHC data
Anti-HIF-1 beta ARNT Rabbit Monoclonal Antibody
Cat # M02263
M02263 is listed for IHC and WB, with Human reactivity (catalog: M02263). Its IHC captions show human renal cancer and mouse ovary paraffin sections; the fixative is unreported (M02263 IHC captions).
Which to pick: For paraffin-section IHC, choose rabbit monoclonal M02263: its human renal cancer image used EDTA retrieval at pH 8.0, 1:50 primary antibody, and DAB detection (M02263 IHC caption; catalog: clone EAD-1). For IF/ICC, M02263 has no listed IF application or IF image (catalog: M02263). For cross-species work, the mouse ovary IHC image is useful preliminary evidence, but listed reactivity is Human only; the caption does not report the fixative (M02263 IHC caption; catalog: M02263).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P27540 (ARNT_HUMAN, Aryl hydrocarbon receptor nuclear translocator).
- Human Protein Atlas. ARNT tissue IHC expression (reliability: Supported).
- Human Protein Atlas. ARNT subcellular location (ICC-IF): Localized to the nucleoplasm and nuclear bodies..
- Human Protein Atlas. ARNT antibody validation summary (2 antibodies).
- Aryl hydrocarbon nuclear translocator (hypoxia inducible factor 1beta) activity is required more during early than late tumor growth. Molecular carcinogenesis 2010 — PMC2938742.
- Aryl hydrocarbon receptor nuclear translocator promotes the proliferation and invasion of clear cell renal cell carcinoma cells potentially by affecting the glycolytic pathway. Oncology letters 2020 — PMC7418509.
- Down-regulation of ARNT promotes cancer metastasis by activating the fibronectin/integrin β1/FAK axis. Oncotarget 2015 — PMC4484474.
- Targeting ARNT attenuates chemoresistance through destabilizing p38α-MAPK signaling in glioblastoma. Cell death & disease 2024 — PMC11133443.
- PubMed PMID:1852076 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
- PubMed PMID:11230166 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for ARNT (Aryl hydrocarbon receptor nuclear translocator). Expected localisation Nuclear staining in most tissues (HPA tissue IHC). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet M02263). Validated IHC antibody: M02263 at 1:50 (the product's own IHC validation image is shown). Controls (HPA): positive Endometrium (Cells in endometrial stroma); negative Cerebellum. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human renal cancer tissue; fixative not specified (datasheet M02263); 2. Fixation: Image fixative and duration unreported (datasheet M02263); 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 M02263); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet M02263); 8. Primary antibody: Rabbit monoclonal (clone EAD-1) anti-ARNT, 1:50 (datasheet M02263); 9. Primary incubation: Overnight at 4 °C (datasheet M02263). Watch for: Fixation: Keep fixation consistent across paraffin sections. (standard IHC practice; not target-specific); Caveat: Staining and RNA show medium consistency (HPA tissue IHC); Isoform / epitope: 4 isoforms; epitope coverage is unspecified (UniProt); Regulation: Expression regulation is unreported (UniProt). Evidence: UniProt P27540, HPA tissue IHC · Supported, HPA ICC-IF · nucleoplasm and nuclear bodies., Datasheet M02263, PMC2938742, PMC7418509. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/ARNT/immunohistochemistry-ihc-guide.