SIRT7 / NAD-dependent protein deacetylase sirtuin-7 · IHC design guide

Design Immunohistochemistry for SIRT7

Plan chromogenic SIRT7 IHC in paraffin sections around nuclear and nucleolar staining (HPA tissue IHC). This guide covers fixation, controls and scoring alongside the catalog antibody’s 0.5–1 μg/ml IHC range (datasheet PB9358).

Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use

Immunohistochemistry protocol sheet for SIRT7 (IHC for SIRT7): expected localisation Nuclear and nucleolar tissue staining (HPA tissue IHC), antibody PB9358, validated IHC image, and IHC protocol steps — Printable **SIRT7** IHC protocol sheet — expected localisation Nuclear and nucleolar tissue staining (HPA tissue IHC), antibody PB9358, controls and protocol steps. Open the full SIRT7 IHC guide →

Navigate to: Protocols Staining pattern Controls Antibodies

SIRT7 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 and nucleolar tissue staining (HPA tissue IHC)
	Staining pattern	Widespread nuclear and nucleolar staining (HPA tissue IHC)
	Antigen retrieval	EDTA pH 8.0 HIER, heat-mediated (datasheet PB9358)
	Positive control ⓘ	Adrenal gland+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 PB9358); optimise locally (standard IHC practice)
	Caveat	RNA–staining consistency is medium; verify tissue signal (HPA tissue IHC)
	Regulation	Stress shifts signal to nucleoplasm (UniProt)
	Isoform / epitope	3 isoforms; antibody isoform coverage is unspecified (UniProt; datasheet PB9358)

Section 1

Recommended SIRT7 IHC & IF Protocols

The catalog antibody’s IHC-P protocol (datasheet: PB9358) is accompanied by published protocols for mouse colon (PMC9687268) and human liver cancer tissue (PMC11164202).

Recommended immunohistochemistry (IHC-P) protocol parameters
Sample	Paraffin-embedded mouse spleen tissue; fixative not specified (datasheet PB9358)
Fixation	Image fixative and duration unreported (datasheet PB9358); 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 PB9358); 20 min, 95–100 °C (standard)
Peroxidase block	3% H2O2, 10 min, room temperature (standard)
Blocking	10% goat serum (datasheet PB9358)
Primary antibody	Rabbit anti-SIRT7, 0.5-1μg/ml (datasheet PB9358)
Primary incubation	Overnight at 4 °C (datasheet PB9358)
Detection	HRP-conjugated secondary, DAB chromogen (datasheet PB9358)
Counterstain	Hematoxylin, blue, dehydrate and mount (standard)
Expected result	SIRT7-positive staining in glandular cells of adrenal gland (HPA tissue IHC: Medium). HPA tissue profile: Ubiquitous nuclear and nucleolar expression. No signal in the no-primary control.

💡Decision noteStart with heat-mediated EDTA retrieval at pH 8.0 (datasheet: PB9358); neither published protocol specifies antigen retrieval (PMC9687268; PMC11164202).

Section 2

What Is the Expected SIRT7 Staining Pattern?

SIRT7 is mainly nuclear, in the nucleolus and nucleoplasm; it has no transmembrane segment (UniProt Q9NRC8). In paraffin-section IHC, expect nuclear or nucleolar staining in the cell populations HPA scores positive, including colon glandular and bronchial respiratory epithelial cells at medium intensity (HPA tissue IHC). HPA calls its tissue staining “Approved,” with medium RNA–staining consistency and external verification pending (HPA tissue IHC).

What am I looking at on my slide?
Nuclear staining, sometimes concentrated in nucleoli, appears in colon glandular cells or bronchial respiratory epithelial cells.	This fits SIRT7's main compartments (UniProt Q9NRC8) and HPA's medium staining in those cell populations (HPA tissue IHC). Judge the compartment within identifiable cells; a positive tissue need not show equal staining in every cell.
Strong staining is confined to cytoplasm, plasma membrane, or extracellular material while nuclei are clear.	This conflicts with the dominant nuclear and nucleolar pattern (UniProt Q9NRC8; HPA tissue IHC). UniProt also lists cytoplasmic localization near the nuclear membrane, so a minor cytoplasmic component alone is inconclusive; predominant nonnuclear color warrants an artefact check.
Color appears in a population HPA lists as “Not detected,” such as adipocytes, while the expected positive cells are unstained.	That combination raises concern for cross-reactivity, endogenous detection activity, or cell-identification error (HPA tissue IHC; general IHC practice). HPA's “Not detected” is an observed result, not proof that every specimen of that cell type must lack SIRT7.
Diffuse color covers nuclei, cytoplasm, and spaces between cells, with little cellular definition.	A diffuse field does not resolve the nuclear pattern reported for SIRT7 (UniProt Q9NRC8; HPA tissue IHC). Background from detection reagents or nonspecific binding is possible (general IHC practice); compare a matched no-primary control before scoring cells positive.
A run shows no nuclear signal in colon glandular cells or another HPA medium population.	This is inconsistent with the cited reference staining, but one negative section does not establish biological absence (HPA tissue IHC). Check tissue preservation, primary-antibody setup, retrieval conditions, and detection controls as general IHC troubleshooting steps.

💡Expected SIRT7 appearanceCall a result positive when identifiable HPA-positive cells show nuclear, often nucleolar, chromogenic signal around the reported medium level; predominantly membrane or extracellular color is suspect (HPA tissue IHC; UniProt Q9NRC8).

How each factor affects the staining
Compartment and cell state	UniProt places SIRT7 mainly in nucleoli and nucleoplasm and reports release into nucleoplasm under stress (UniProt Q9NRC8). A less conspicuous nucleolar focus can therefore remain compatible with nuclear staining; do not infer a stress response from one IHC section.
Cell-population differences	HPA reports medium staining in colon glandular cells, low staining in duodenal glandular cells, and no detected staining in adipocytes (HPA tissue IHC). Select and score controls by the named cell population, not by tissue name alone.
Strength of tissue evidence	The overall tissue pattern is “Approved,” with medium RNA–staining consistency and external verification pending (HPA tissue IHC). HPA lists two antibodies with “Approved” IHC status, HPA053669 and CAB037261 (HPA antibodies); this does not establish identical behavior for every antibody.
Protein form and topology	UniProt lists three SIRT7 isoforms, a 1–400 chain, no signal peptide, and no transmembrane segment (UniProt Q9NRC8). These facts support an intracellular interpretation but do not identify an antibody epitope or predict how antigen retrieval will affect staining.

Why is my staining missing, weak or wrong?
Situation	Likely cause	Next action
Expected nuclear signal is absent from an HPA-positive control.	The staining run may have failed, or the sampled cells may differ from the HPA example (HPA tissue IHC; general IHC practice).	Confirm the named cell population, then review section quality, antibody setup, retrieval conditions, and detection controls. Optimize retrieval empirically; target-specific fixation sensitivity is unreported here.
Most color sits outside nuclei.	Predominantly nonnuclear staining conflicts with the main SIRT7 pattern (UniProt Q9NRC8; HPA tissue IHC). Nonspecific staining is possible (general IHC practice).	Check a matched no-primary control and reassess cell boundaries and nuclear counterstain. Treat minor perinuclear cytoplasm cautiously because cytoplasmic localization is also listed (UniProt Q9NRC8).
An HPA “Not detected” cell population stains strongly.	Cross-reactivity, endogenous detection activity, or misidentified cells are possible (HPA tissue IHC; general IHC practice).	Compare the positive and no-primary sections at the same detection settings; verify cell identity. Keep the finding provisional because the HPA category describes observed staining, not an absolute biological negative.
The whole section develops hazy chromogen.	Diffuse background can arise from nonspecific binding or the detection system (general IHC practice). It obscures the expected nuclear pattern (HPA tissue IHC).	Inspect no-primary and reagent controls, then review blocking, washes, primary-antibody concentration, and chromogen development as general IHC variables. Score only resolved cellular staining.
Nuclear staining appears, but distinct nucleoli are hard to see.	HPA describes nuclear and nucleolar tissue staining, while UniProt also places SIRT7 in the nucleoplasm (HPA tissue IHC; UniProt Q9NRC8).	Evaluate the full nuclear distribution in identifiable HPA-positive cells before rejecting the run; avoid requiring a discrete nucleolar dot in every positive nucleus.
IF/ICC: what pattern should appear?	HPA's ICC-IF summary reports supported nucleoplasmic localization with additional supported nuclear-speckle localization (HPA subcellular).	Expect chiefly nucleoplasmic fluorescence, with possible nuclear speckles (HPA subcellular). Use the separate IF/ICC guide for its workflow; the IHC tissue pattern does not specify an IF protocol.

Source: UniProt Q9NRC8 Human Protein Atlas tissue Human Protein Atlas subcellular

Experiment evidence

IHC & IF images showing SIRT7 staining

IHC analysis of SIRT7 using anti-SIRT7 antibody (PB9358). SIRT7 was detected in a paraffin-embedded section of mouse spleen tissue. Heat mediated antigen retrieval was performed in EDTA buffer (pH 8.0, epitope retrieval solution). The tissue section was blocked with 10% goat serum. The tissue section was then incubated with 1 μg/ml rabbit anti-SIRT7 Antibody (PB9358) overnight at 4°C. Peroxidase Conjugated Goat Anti-rabbit IgG was used as secondary antibody and incubated for 30 minutes at 37°C. The tissue section was developed using HRP Conjugated Rabbit IgG Super Vision Assay Kit (Catalog # SV0002) with DAB as the chromogen.

PB9358 · IHCIHC analysis of SIRT7 using anti-SIRT7 antibody (PB9358). SIRT7 was detected in a paraffin-embedded section of mouse spleen tissue. Heat med

IHC analysis of SIRT7 using anti-SIRT7 antibody (PB9358). SIRT7 was detected in a paraffin-embedded section of rat spleen tissue. Heat mediated antigen retrieval was performed in EDTA buffer (pH 8.0, epitope retrieval solution). The tissue section was blocked with 10% goat serum. The tissue section was then incubated with 1 μg/ml rabbit anti-SIRT7 Antibody (PB9358) overnight at 4°C. Peroxidase Conjugated Goat Anti-rabbit IgG was used as secondary antibody and incubated for 30 minutes at 37°C. The tissue section was developed using HRP Conjugated Rabbit IgG Super Vision Assay Kit (Catalog # SV0002) with DAB as the chromogen.

PB9358 · IHCIHC analysis of SIRT7 using anti-SIRT7 antibody (PB9358). SIRT7 was detected in a paraffin-embedded section of rat spleen tissue. Heat media

HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000187531-SIRT7/tissue/cerebral+cortex#imid_16689599

HPA · EsophagusHuman Protein Atlas IHC, Esophagus. Source: https://www.proteinatlas.org/ENSG00000187531-SIRT7/tissue/esophagus#imid_16689579

HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000187531-SIRT7/tissue/colon#imid_16690109

HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000187531-SIRT7/tissue/liver#imid_16690094

HPA · ICC-IF HEK293Human Protein Atlas immunofluorescence, HEK293, antibody HPA027284; green = SIRT7, blue = nucleus, red = microtubules.

← swipe / scroll for more images →

Real IHC / IF data behind the staining-pattern expectations in this section.

Sample controls for SIRT7 IHC & IF

🧪Run breast first: glandular cells should show SIRT7 staining (HPA: Medium in breast glandular cells). Use adipose tissue as the negative comparator (HPA: Not detected in adipocytes); on the breast slide, assess adjacent cells without nuclear signal as internal background controls, without assuming they are SIRT7-negative.

Positive control tissue: Adrenal gland (Glandular cells, HPA Medium)

Negative control tissue: Adipose tissue (HPA Not detected)

ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show SIRT7 in HEK293, U-251MG, U2OS, A-549, PC-3, NIH 3T3, with annotated localisation: Nucleoplasm (supported) (HPA subcellular).

Technical controls: Include a no-primary, secondary-only control and a concentration-matched rabbit isotype control (caption: rabbit anti-SIRT7 primary and goat anti-rabbit secondary). Use SIRT7-knockout material as a biological negative where available; quench endogenous peroxidase and check for residual brown background in the breast section (caption: HRP/DAB detection; standard IHC practice).

⚠️Feasibility: The selected PB9358 paraffin-section caption reports EDTA retrieval at pH 8.0, followed by 1 μg/ml primary antibody overnight at 4°C; this shows a retrieval condition used for mouse spleen, not that retrieval is universally required (caption: PB9358 mouse spleen IHC). A target-specific fixation window or fixation effect is unreported, and the selected caption does not state the fixative (caption: fixative not stated). The supplied evidence does not establish that frozen sections or IF are easier than paraffin IHC; when scoring breast, separate nuclear staining from residual HRP/DAB background (HPA: Medium in breast glandular cells; UniProt Q9NRC8: mainly nucleolar and nucleoplasmic; caption: HRP/DAB detection).

HPA tissue IHC evidence for SIRT7

Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Approved — Medium consistency between antibody staining and RNA expression data. Pending external verification.). 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	Medium	Protein (IHC)	HPA →
Breast	Glandular cells	Medium	Protein (IHC)	HPA →
Bronchus	Respiratory epithelial cells	Medium	Protein (IHC)	HPA →
Caudate	Glial cells	Medium	Protein (IHC)	HPA →
Cerebellum	Cells in granular layer	Medium	Protein (IHC)	HPA →

Undetected expression · recommended negative controls

Tissue	Cell type	Level	Evidence	Source
Adipose tissue	Adipocytes	Not detected	Protein (IHC)	HPA →
Liver	Cholangiocytes	Not detected	Protein (IHC)	HPA →
Lung	Alveolar cells	Not detected	Protein (IHC)	HPA →
Ovary	Ovarian stroma cells	Not detected	Protein (IHC)	HPA →
Parathyroid gland	Glandular cells	Not detected	Protein (IHC)	HPA →

Section 3

Advanced SIRT7 IHC Tips

Use the paraffin section protocol as the starting point, then troubleshoot signal by compartment, cell type and matched controls.

Which retrieval condition should I use when SIRT7 staining is weak?

Start with heat-mediated EDTA pH 8.0 antigen retrieval for paraffin sections (datasheet PB9358). This condition accompanied SIRT7 staining in a mouse spleen section with the catalog antibody (caption PB9358). If nuclear signal is weak, compare a modest range of heating times while keeping buffer, section thickness, antibody concentration and detection conditions constant; excessive heating can damage tissue morphology (standard IHC practice). Include a section processed without primary antibody to assess detection background, and evaluate improvement in intact nuclei rather than at section edges (standard IHC practice). Expected nuclear and nucleolar localisation provides a useful readout (UniProt Q9NRC8; HPA tissue IHC).

Could fixation explain weak or uneven SIRT7 staining?

Target-specific fixation sensitivity is unknown: the selected paraffin section caption does not state its fixative (caption PB9358). Record fixative, fixation duration and specimen thickness for each block, then compare sections from consistently processed specimens using the same retrieval and detection conditions (standard IHC practice). If staining varies between blocks, assess preservation and staining of a suitable control alongside SIRT7 before attributing the difference to protein abundance (standard IHC practice). Do not infer a preferred fixative or a SIRT7-specific fixation effect from its nuclear localisation, topology, modifications or tissue staining pattern (UniProt Q9NRC8; HPA tissue IHC).

How should I assess nucleolar, nucleoplasmic and cytoplasmic SIRT7 staining?

Assess nuclear staining first: SIRT7 is reported mainly in nucleoli and nucleoplasm, with additional chromosomal and cytoplasmic localisation (UniProt Q9NRC8). The tissue IHC profile describes ubiquitous nuclear and nucleolar expression, while the subcellular IF record supports nucleoplasmic and nuclear speckle localisation (HPA tissue IHC; HPA subcellular). If nucleolar signal appears reduced, compare nuclei in well-preserved regions and review specimen context, since stress can redistribute SIRT7 into the nucleoplasm (UniProt Q9NRC8, PubMed:24207024). Score cytoplasmic staining separately and check whether it is reproducible in comparable cells and absent from the no-primary control (standard IHC practice).

Can this IHC stain distinguish SIRT7 isoforms or epitope masking?

Do not assign an isoform from staining alone: the record lists 3 SIRT7 isoforms, while the supplied caption does not identify the antibody epitope (UniProt Q9NRC8; caption PB9358). The annotated sirtuin-type deacetylase domain spans residues 82–329, and alternative methylation is annotated at residue 388 (UniProt Q9NRC8). These features do not establish which isoforms the catalog antibody detects or whether a modification affects binding (UniProt Q9NRC8; caption PB9358). If isoform recognition matters, obtain the immunogen sequence and compare it with isoform sequences; use independently validated controls before interpreting differences between tissues (standard IHC practice).

How should I investigate SIRT7 by multiplex IF after seeing IHC staining?

Treat IF as a separate optimisation: the supplied catalog antibody evidence describes chromogenic staining of a paraffin mouse spleen section, with no IF conditions for that antibody (caption PB9358). Pair SIRT7 with a marker validated for the cell population under study and a nuclear counterstain so that nuclear assignment can be checked cell by cell (standard IF practice; UniProt Q9NRC8). Choose fluorophores in channels with low measured tissue autofluorescence, and include single-stain and no-primary controls to assess bleed-through and background (standard IF practice). Because SIRT7 has no transmembrane segment and is mainly nuclear, optimise permeabilisation for nuclear access without disrupting nucleolar structure (UniProt Q9NRC8; standard IF practice).

What should I check when SIRT7 DAB staining is diffuse?

The selected paraffin section used 10% goat serum blocking, 1 μg/ml primary antibody overnight at 4°C, and an HRP/DAB detection workflow (caption PB9358). Check a no-primary section and inspect whether diffuse colour persists in areas without plausible nuclear staining; block endogenous peroxidase and optimise washing and DAB development as general IHC steps (standard IHC practice). If background rises with primary antibody, titrate it around the documented condition while holding retrieval and development constant (caption PB9358; standard IHC practice). Judge improvement by clearer nuclear or nucleolar contrast with preserved morphology, consistent with reported SIRT7 localisation (UniProt Q9NRC8; HPA tissue IHC).

How should I quantify SIRT7 across paraffin sections? ⚠ ANSWER MARKED FOR VERIFICATION

Define the cell population and tissue region before scoring, then record the percentage of nuclei staining at each intensity to calculate a nuclear H-score (standard IHC practice; HPA tissue IHC). If discrete positive cells are the question, report positive nuclei per mm² and the total nuclei or tissue area examined (standard IHC practice). Score nucleolar and nucleoplasmic patterns separately when they are distinguishable, because both are reported SIRT7 locations (UniProt Q9NRC8). Normalise comparisons to eligible intact nuclei or matched tissue area, use the same threshold and imaging settings, and exclude folds, edges and necrotic regions by a prespecified rule (standard IHC practice).

How can I distinguish genuine SIRT7 staining from artefact?

Favour reproducible staining in intact nuclei, including nucleolar or nucleoplasmic patterns, because these are established SIRT7 locations (UniProt Q9NRC8; HPA tissue IHC). Interpret a positive cell in its tissue context: HPA reports medium staining in several specified cell populations but also lists populations where staining was not detected (HPA tissue IHC). Treat isolated edge staining, necrotic regions and colour that persists without primary antibody as possible section or detection artefacts (standard IHC practice). If cytoplasmic signal is prominent, evaluate it separately against matched controls; cytoplasmic localisation is reported, so compartment alone does not establish either specificity or artefact (UniProt Q9NRC8; standard IHC practice).

Boster reagents

Best SIRT7 / NAD-dependent protein deacetylase sirtuin-7 IHC Antibodies

PB9358 has real IHC data from paraffin sections of mouse and rat spleen (catalog: PB9358 image captions); human reactivity is listed without a human IHC image (catalog: PB9358 reactivity and image captions).

Real IHC data

Anti-SIRT7 Antibody ®

Cat # PB9358

View product →

PB9358 is listed for IHC and has images from paraffin sections of mouse and rat spleen (catalog: PB9358 applications and image captions). Human is listed as reactive, but no human IHC image is provided (catalog: PB9358 reactivity and image captions).

Which to pick: Choose PB9358 for paraffin-section IHC; its captions document heat retrieval in EDTA at pH 8.0 and primary antibody at 1 μg/ml in mouse and rat spleen (catalog: PB9358 image captions). No IF/ICC option is supported by this catalog entry, which lists IHC and WB and provides no IF image or dilution (catalog: PB9358 applications and IF fields). PB9358 lists human, mouse, and rat reactivity, although its IHC images cover mouse and rat only; clonality and the tissue fixative are unreported (catalog: PB9358 reactivity, clone field, and image captions).

Each figure is that product's own IHC / IF validation image from its datasheet.

References

UniProt Consortium. UniProt entry Q9NRC8 (SIR7_HUMAN, NAD-dependent protein deacetylase sirtuin-7).
Human Protein Atlas. SIRT7 tissue IHC expression (reliability: Approved).
Human Protein Atlas. SIRT7 subcellular location (ICC-IF): Mainly localized to the nucleoplasm. In addition localized to the nuclear speckles..
Human Protein Atlas. SIRT7 antibody validation summary (4 antibodies).
Sirtuin 7: a new marker of aggressiveness in prostate cancer. Oncotarget 2017 — PMC5652781.
SIRT7, H3K18ac, and ELK4 Immunohistochemical Expression in Hepatocellular Carcinoma. Journal of pathology and translational medicine 2016 — PMC5042897.
Sirtuin 7 Inhibitor Attenuates Colonic Mucosal Immune Activation in Mice-Potential Therapeutic Target in Inflammatory Bowel Disease. Biomedicines 2022 — PMC9687268.
Analysis of the Expression and Prognostic Value of SIRTs in Hepatocellular Carcinoma. International journal of general medicine 2024 — PMC11164202.
PubMed PMID:10873683 — UniProt-cited evidence.
PubMed PMID:14702039 — UniProt-cited evidence.
PubMed PMID:16625196 — UniProt-cited evidence.