This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
SOD2 / Superoxide dismutase [Mn], mitochondrial · IHC design guide
Design Immunohistochemistry for SOD2
Plan SOD2 staining in paraffin sections around the cytoplasmic mitochondrial pattern reported in tissue IHC (HPA tissue IHC). This guide covers fixation consistency, antibody dilution, chromogenic detection and interpretation, including the reported medium agreement between staining and RNA (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
SOD2 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 | Cytoplasmic mitochondrial staining (HPA tissue IHC); matrix target (UniProt) | |
| Staining pattern | General cytoplasmic staining with a mitochondrial pattern (HPA tissue IHC) | |
| Antigen retrieval | Citrate pH 6 HIER, heat-mediated (datasheet PB9442) | |
| Positive control | Adrenal gland+4 more · see all | |
| Negative control | None in HPA (detected in all 44 tissues); use no-primary + isotype controls |
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; restaining pending (HPA tissue IHC) | |
| Regulation | No expression regulator annotated (UniProt) | |
| Isoform / epitope | 4 isoforms; chain 25–222; epitope impact unknown (UniProt) |
Section 1
Recommended SOD2 IHC & IF Protocols
The catalog antibody’s IHC-P protocol (datasheet PB9442) is accompanied by published SOD2 protocols for rat ovary (PMC11481372) and cervical carcinoma (PMC5955150; PMC8147985).
| Sample | Paraffin-embedded human mammary cancer tissue; fixative not specified (datasheet PB9442) |
| Fixation | Image fixative and duration unreported (datasheet PB9442); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: Citrate pH 6, 20 min (datasheet PB9442) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet PB9442) |
| Primary antibody | Rabbit anti-SOD2, 0.5-1μg/ml (datasheet PB9442) |
| Primary incubation | Overnight at 4 °C (datasheet PB9442) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet PB9442) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | SOD2-positive staining in glandular cells of adrenal gland (HPA tissue IHC: High). HPA tissue profile: General cytoplasmic expression with a mitochondrial pattern. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated citrate pH 6 for the catalog antibody (datasheet PB9442). The automated studies used heated Tris pH 8 (PMC11481372; PMC8147985).
Section 2
What Is the Expected SOD2 Staining Pattern?
SOD2 resides in the mitochondrial matrix and has no transmembrane segment (UniProt P04179 topology). In paraffin sections, expect cytoplasmic staining with a mitochondrial pattern, including strong signal in the glandular, respiratory epithelial, and neuronal cell populations listed by HPA (HPA tissue IHC: High). HPA rates the tissue pattern Supported, with medium agreement between staining and RNA data; restaining is pending (HPA tissue IHC: reliability).
| Cytoplasmic staining with a mitochondrial pattern in glandular cells of colon, duodenum, appendix, or adrenal gland (HPA tissue IHC: High). | This matches the reported tissue pattern and the mitochondrial matrix location (HPA tissue IHC: profile; UniProt P04179 topology). Judge the pattern within the named cells; staining elsewhere in the section needs its own assessment. |
| Predominantly nuclear or sharply membrane-bound staining, with little cytoplasmic signal. | That distribution conflicts with the reported mitochondrial matrix location and tissue pattern (UniProt P04179 topology; HPA tissue IHC: profile). Check morphology and controls before treating it as SOD2; this appearance alone does not identify the artefact. |
| Strong chromogen in a cell population outside the HPA-listed positive populations. | The supplied HPA record does not classify every other cell as negative (HPA tissue IHC: positive list; negative list empty). Consider cross-reactivity or endogenous detection activity, and compare with an appropriate reagent control (standard IHC practice). |
| Broad, even colour across cells and surrounding tissue, obscuring intracellular detail. | Diffuse background cannot establish the mitochondrial pattern reported for SOD2 (HPA tissue IHC: profile). Review reagent and detection controls, washing, and chromogen development as general IHC checks (standard IHC practice). |
| No discernible signal in HPA-listed high-staining cells, while tissue morphology remains interpretable. | This conflicts with the reported high staining in those specific cells (HPA tissue IHC: High). First check the run's positive control and detection steps; a blank section alone cannot distinguish technical failure from sample variation (standard IHC practice). |
💡Expected SOD2 appearanceCall the result positive when the relevant HPA-listed cells show High cytoplasmic staining with a mitochondrial pattern (HPA tissue IHC: High; profile); isolated nuclear or membrane-bound colour does not match SOD2's matrix location (UniProt P04179 topology).
| Cell population and tissue | HPA reports High staining in specified glandular, respiratory epithelial, and neuronal cells, but Low staining in spleen red pulp cells (HPA tissue IHC: positive and low lists). Score the named population rather than assigning one intensity to an entire tissue. |
| Tissue evidence and validation | The IHC tissue profile is Supported, with medium staining–RNA consistency and restaining pending; antibody HPA001814 is IHC Supported (HPA tissue IHC: reliability; HPA antibody validation). These ratings support interpretation without making every unexpected signal specific. |
| Intracellular location and processing | SOD2 is a mitochondrial matrix protein without a transmembrane segment; UniProt lists the mature chain as residues 25–222 (UniProt P04179 topology; processing). Interpret chromogen distribution at the cell level; the record supplies no antibody epitope or target-specific retrieval condition. |
| Expression evidence | Bone marrow is tissue enhanced by RNA specificity, while the supplied IHC list gives no bone marrow staining level (HPA tissue IHC: RNA specificity; positive and low lists). Do not convert RNA enrichment into an expected chromogenic intensity. |
| IF/ICC Q: What pattern should appear? | A: Mitochondrial localisation is supported in ICC-IF, with U2OS images listed; HPA001814 is ICC Supported (HPA subcellular: main location and images; HPA antibody validation). This supports a localisation comparison, not an IF protocol or an IHC intensity threshold. |
| Situation | Likely cause | Next action |
|---|---|---|
| Known HPA-positive cells show no chromogen. | A failed staining or detection step is possible; the HPA observation alone does not identify which step failed (HPA tissue IHC: High; standard IHC practice). | Verify the run's positive control, antibody incubation, detection reagents, and chromogen development (standard IHC practice). Then compare cells named in the HPA record, such as colon glandular cells (HPA tissue IHC: High). |
| Signal is mainly nuclear or outlines the plasma membrane. | This distribution differs from mitochondrial matrix localisation (UniProt P04179 topology; HPA tissue IHC: profile). | Review cell morphology and the staining controls, then reassess whether cytoplasmic signal has a mitochondrial pattern (standard IHC practice; HPA tissue IHC: profile). Do not score compartmentally discordant colour as a clear positive. |
| Colour appears in unexpected cell populations. | Cross-reactivity or endogenous detection activity is possible, but the supplied HPA list gives no formal negative population (HPA tissue IHC: negative list empty; standard IHC practice). | Compare a reagent control with the stained section and check whether the named HPA-positive cells show the expected pattern (standard IHC practice; HPA tissue IHC: positive list). |
| Diffuse colour obscures intracellular localisation. | General background can prevent assessment of the reported mitochondrial pattern (HPA tissue IHC: profile; standard IHC practice). | Inspect the reagent control and review blocking, washes, and chromogen development as general IHC workflow checks (standard IHC practice). Reassess only when cell-level localisation is visible. |
| A spleen red pulp result seems weaker than a positive reference. | HPA reports Low staining in red pulp cells, compared with High staining in several named cell populations elsewhere (HPA tissue IHC: low and positive lists). | Compare like cell populations and check the run control before calling weak red pulp staining a failed assay (HPA tissue IHC: low list; standard IHC practice). |
| Retrieval changes the amount of signal between runs. | Target-specific fixation effects are not established by the supplied assay evidence. Verify with a matched IHC source before attributing a result to fixation. | Document the retrieval conditions, compare run controls, and assess pattern and background together (standard IHC practice). Do not attribute the change to a proven SOD2 epitope effect. |
Experiment evidence
IHC & IF images showing SOD2 staining
PB9442 · IHCIHC analysis of SOD2 using anti-SOD2 antibody (PB9442). SOD2 was detected in paraffin-embedded section of human mammary cancer tissue. Heat
PB9442 · IHCIHC analysis of SOD2 using anti-SOD2 antibody (PB9442). SOD2 was detected in paraffin-embedded section of human mammary cancer tissue. Heat
M00349-2 · IHCIHC analysis of SOD2 (acetyl K68) using anti-SOD2 (acetyl K68) antibody (M00349-2). SOD2 (acetyl K68) was detected in a paraffin-embedded se
M00349-2 · IHCIHC analysis of SOD2 (acetyl K68) using anti-SOD2 (acetyl K68) antibody (M00349-2). SOD2 (acetyl K68) was detected in a paraffin-embedded se
M00349-3 · IHCIHC analysis of SOD2 using anti-SOD2 antibody (M00349-3). SOD2 was detected in a paraffin-embedded section of human adenocarcinoma of the ri
M00349-3 · IHCIHC analysis of SOD2 using anti-SOD2 antibody (M00349-3). SOD2 was detected in a paraffin-embedded section of human liver cancer tissue. Hea
M00349 · IHCIHC analysis of SOD2 using anti-SOD2 antibody (M00349). SOD2 was detected in a paraffin-embedded section of human liver cancer tissue. Heat
M00349 · IHCIHC analysis of SOD2 using anti-SOD2 antibody (M00349). SOD2 was detected in a paraffin-embedded section of human liver cancer tissue. Heat
M33970-1 · IHCM33970-1 staining SODM in human skeletal muscle sections by Immunohistochemistry (IHC-P -paraformaldehyde-fixed, paraffin-embedded sections)
M33970-1 · IHCM33970-1 staining SODM in human brain sections by Immunohistochemistry (IHC-P -paraformaldehyde-fixed, paraffin-embedded sections). Tissue w
PA1776 · IHCIHC analysis of SOD2/Mnsod using anti-SOD2/Mnsod antibody (PA1776). SOD2/Mnsod was detected in paraffin-embedded section of rat brain tissue
PA1776 · IHCIHC analysis of SOD2/Mnsod using anti-SOD2/Mnsod antibody (PA1776). SOD2/Mnsod was detected in paraffin-embedded section of human intestinal
PA1776 · IFIF analysis of SOD2 using anti-SOD2 antibody (PA1776). SOD2 was detected in an immunocytochemical section of U2OS cells. Enzyme antigen retr
M00349-5 · IHCHuman colon was stained with anti-SOD2 rabbit antibody
M00349-5 · IHCHuman kidney was stained with anti-SOD2 rabbit antibody
M33970 · IHCFormalin-fixed and paraffin-embedded human lung carcinoma tissue reacted with SOD2 Monoclonal Antibody , which was peroxidase-conjugated to
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000291237-SOD2/tissue/cerebral+cortex#imid_967808
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000291237-SOD2/tissue/colon#imid_967726
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000291237-SOD2/tissue/liver#imid_967743
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000291237-SOD2/tissue/kidney#imid_967744
HPA · ICC-IF U2OSHuman Protein Atlas immunofluorescence, U2OS, antibody HPA001814; green = SOD2, blue = nucleus, red = microtubules.
HPA · ICC-IF U2OSHuman Protein Atlas immunofluorescence, U2OS, antibody HPA001814; green = SOD2, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for SOD2 IHC & IF
🧪Run adrenal gland first: glandular cells should stain strongly (HPA: High in adrenal gland glandular cells). HPA detects SOD2 in all 44 scored tissues, so there is no supported negative tissue; no-primary and isotype controls carry the negative, while any cells used as internal negative comparators should show only background chromogen, without granular cytoplasmic staining (HPA: no negative tissue rows; UniProt P04179: mitochondrial matrix).
Positive control tissue: Adrenal gland (Glandular cells, HPA High)
Negative control tissue: None in HPA: SOD2 is detected in all 44 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 SOD2 in U2OS, with annotated localisation: Mitochondria (supported) (HPA subcellular).
Technical controls: Include a no-primary (secondary-only) control, an isotype control matched to the primary antibody’s host species and clonality, and a validated SOD2 knockout sample as a biological negative (PB9442 caption: rabbit primary; standard IHC control practice). For adrenal gland, check endogenous peroxidase and biotin background when using the caption’s biotinylated secondary, SABC and DAB detection (PB9442 caption: SABC/DAB).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected PB9442 tissue-IHC caption does not state a fixative (PB9442 caption). Citrate retrieval at pH 6 for 20 minutes was used in the paraffin-section example, but whether SOD2 staining depends on that retrieval condition is unreported; the supplied evidence does not establish that frozen sections or IF are easier (PB9442 caption; HPA: mitochondrial ICC-IF localization in U2OS). In adrenal gland, endogenous peroxidase or biotin could produce misleading chromogenic signal with SABC/DAB, so interpret staining against the detection controls (PB9442 caption: SABC/DAB; standard IHC practice).
HPA tissue IHC evidence for SOD2
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Supported — Medium consistency between antibody staining and RNA expression data. Pending restaining.). 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 → |
| Appendix | Glandular cells | High | Protein (IHC) | HPA → |
| Bronchus | Respiratory epithelial cells | High | Protein (IHC) | HPA → |
| Caudate | Neuronal cells | High | Protein (IHC) | HPA → |
| Cerebellum | Cells in granular layer | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| None in HPA: SOD2 is detected in all 44 scored tissues. Use a no-primary (secondary-only) and an isotype control instead. | ||||
Section 3
Advanced SOD2 IHC Tips
Troubleshoot SOD2 staining by checking retrieval, assay controls, and the expected mitochondrial pattern before interpreting chromogenic signal (datasheet PB9442; UniProt P04179; HPA tissue IHC).
What should I change when SOD2 staining is weak after retrieval?
Start with heat-mediated antigen retrieval in citrate buffer at pH 6 for 20 minutes (datasheet PB9442). Check that sections remain covered by buffer during heating and cool consistently before blocking; uneven heating can create patchy chromogenic staining (standard IHC practice). The PB9442 caption reports SOD2 detection in a paraffin-embedded human mammary cancer section after this retrieval, followed by 10% goat serum block and 1 μg/ml primary antibody overnight at 4°C (datasheet PB9442). If staining remains weak, compare retrieval duration on adjacent sections while holding primary concentration, detection chemistry, and development time constant (standard IHC practice).
How should I troubleshoot fixation-related loss of SOD2 staining?
Target-specific fixation sensitivity is unknown: the selected PB9442 tissue caption describes a paraffin-embedded section but does not state its fixative (datasheet PB9442). Record the fixative, fixation duration, processing history, and section age for each specimen, then compare like with like when assessing staining differences (standard IHC practice). If a batch stains poorly, run a known positive section through the same citrate pH 6, 20-minute retrieval and detection sequence before changing several steps (datasheet PB9442; standard IHC practice). Treat a change associated with fixation history as a specimen-level observation, requiring controlled comparison before attributing it to SOD2 itself (standard IHC practice).
Where should convincing chromogenic SOD2 signal appear?
Expect a cytoplasmic staining pattern compatible with mitochondria, since SOD2 localizes to the mitochondrial matrix and HPA describes general cytoplasmic expression with a mitochondrial pattern (UniProt P04179 subcellular location; HPA tissue IHC). Assess staining at a magnification that resolves cytoplasmic texture, then compare cells within the same section under identical DAB development conditions (standard IHC practice). Nuclear-only or sharply plasma-membrane-restricted signal does not match the reported location and needs review of counterstain, background, and antibody controls (UniProt P04179 subcellular location; standard IHC practice). HPA lists high staining in colon glandular cells, which can provide a documented reference pattern for comparison (HPA: High in colon glandular cells).
Can SOD2 isoforms or modifications explain inconsistent staining?
SOD2 has 4 annotated isoforms, and the canonical protein is processed to a chain spanning residues 25–222 (UniProt P04179 isoforms and processing). Its record also lists nitration at residue 58 and alternative acetylation or succinylation at residues 68 and 75 (UniProt P04179 modified residues). These annotations alone do not establish which sequence the catalog antibody recognizes or whether a modification changes staining (UniProt P04179 annotations; standard IHC interpretation). If samples differ, consult the antibody's stated immunogen and test matched sections with the same retrieval, 1 μg/ml primary concentration, and DAB development before assigning the difference to an isoform or epitope (datasheet PB9442; standard IHC practice).
How can IF help check a questionable SOD2 IHC pattern?
On a parallel specimen, compare SOD2 fluorescence with a validated epithelial lineage marker when examining glandular cells; HPA reports high SOD2 staining in colon glandular cells (HPA: High in colon glandular cells; standard IF practice). Choose spectrally separated fluorophores and consider a red or far-red SOD2 channel when green tissue autofluorescence obscures signal (standard IF practice). SOD2 is in the mitochondrial matrix and has no annotated transmembrane segment, so matrix access requires permeabilisation across cell and mitochondrial membranes; the catalog antibody's epitope is unspecified (UniProt P04179 topology and subcellular location; standard IF practice). Include single-label and secondary-only controls before comparing punctate fluorescence with the chromogenic pattern (standard IF practice).
What should I check when DAB obscures SOD2 staining?
First compare a no-primary control with the stained section to identify signal arising from detection reagents or tissue rather than primary-antibody binding (standard IHC practice). The PB9442 example used a biotinylated secondary, streptavidin–biotin detection, and DAB, so background in that workflow warrants checks of endogenous peroxidase and endogenous biotin (datasheet PB9442; standard IHC practice). Apply a peroxidase block and appropriate biotin control as workflow controls, then keep DAB development time consistent across comparison sections (standard IHC practice). Reassess whether remaining cytoplasmic signal follows the reported mitochondrial pattern instead of diffuse deposits or tissue edges (HPA tissue IHC; standard IHC practice).
How should I score SOD2 staining across sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the analysis region and cell population before scoring, excluding folds, torn edges, and necrotic areas by the same rules in every section (standard IHC practice). For comparable viable cells, report the percentage of positive cells and an H-score calculated as the sum of each intensity category's percentage multiplied by its 0–3 intensity score (standard IHC practice). Normalize counts to the number of evaluable cells, or report positive-cell density per mm² of viable tissue when cell counts are impractical (standard IHC practice). Keep retrieval at citrate pH 6 and DAB development conditions consistent, and state whether scoring includes only cytoplasmic staining compatible with mitochondria (datasheet PB9442; HPA tissue IHC; standard IHC practice).
When is apparent SOD2 positivity likely to be artefactual?
Give greatest weight to cytoplasmic signal compatible with mitochondria in intact cells, because SOD2 is a mitochondrial matrix protein and HPA describes a mitochondrial cytoplasmic pattern (UniProt P04179 subcellular location; HPA tissue IHC). HPA reports high staining in colon glandular cells and low staining in spleen red-pulp cells, but its tissue IHC reliability is Supported with medium RNA concordance and pending restaining (HPA tissue IHC). Investigate isolated nuclear or membrane staining, edge accentuation, and staining confined to necrotic material before calling a specimen positive (UniProt P04179 subcellular location; standard IHC practice). A no-primary control and peroxidase check help distinguish endogenous enzyme signal from antibody-dependent DAB staining (standard IHC practice).
Boster reagents
Best SOD2 / Superoxide dismutase [Mn], mitochondrial IHC Antibodies
Anti-SOD2 antibodies have IHC images from human and rat paraffin sections and human skeletal muscle sections (catalog image captions); PA1776 also has an IF image from U2OS cells (PA1776 IF caption).
Real IHC data
Anti-SOD2 Antibody ®
Cat # PB9442
Real IHC data
Anti-SOD2 (acetyl K68) Rabbit Monoclonal Antibody
Cat # M00349-2
Real IHC data
Anti-SOD2 Antibody ® (monoclonal, 2B12B1)
Cat # M00349-3
Real IHC data
Anti-SOD2/Mnsod Rabbit Monoclonal Antibody
Cat # M00349
Real IHC data
Anti-SODM Antibody
Cat # M33970-1
Real IHC data
Anti-SOD2 Antibody ®
Cat # PA1776
PB9442 was shown on human mammary cancer, M00349-2 on human breast cancer, M00349-3 on human right-colon adenocarcinoma, and M00349 on human liver cancer paraffin sections (respective IHC captions). M33970-1 was shown on human skeletal muscle sections, and PA1776 on rat brain paraffin sections (respective IHC captions).
Which to pick: For tissue IHC, choose PB9442 for citrate pH 6 retrieval or M00349 for EDTA pH 8 retrieval, following each antibody’s own paraffin-section caption; neither caption reports the fixative (PB9442 and M00349 IHC captions). For IF/ICC, choose PA1776: ICC is listed and its IF image shows U2OS cells (PA1776 applications and IF caption). For IHC across human, mouse and rat samples, PB9442 and PA1776 list all three species; select M00349-2 when acetyl-K68 SOD2 is the target (catalog reactivity, applications and titles).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P04179 (SODM_HUMAN, Superoxide dismutase [Mn], mitochondrial).
- Human Protein Atlas. SOD2 tissue IHC expression (reliability: Supported).
- Human Protein Atlas. SOD2 subcellular location (ICC-IF): Localized to the mitochondria..
- Human Protein Atlas. SOD2 antibody validation summary (1 antibodies).
- Post-mortem Findings of Inflammatory Cells and the Association of 4-Hydroxynonenal with Systemic Vascular and Oxidative Stress in Lethal COVID-19. Cells 2022 — PMC8834180.
- Melatonin increases superoxide dismutase 2 (SOD2) levels and improves rat ovarian graft function after transplantation. Journal of ovarian research 2024 — PMC11481372.
- Strong SOD2 expression and HPV-16/18 positivity are independent events in cervical cancer. Oncotarget 2018 — PMC5955150.
- High Expression of SOD2 Protein Is a Strong Prognostic Factor for Stage IIIB Squamous Cell Cervical Carcinoma. Antioxidants (Basel, Switzerland) 2021 — PMC8147985.
- PubMed PMID:2462451 — UniProt-cited evidence.
- PubMed PMID:3684581 — UniProt-cited evidence.
- PubMed PMID:3399391 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for SOD2 (Superoxide dismutase [Mn], mitochondrial). Expected localisation Cytoplasmic mitochondrial staining (HPA tissue IHC); matrix target (UniProt). Antigen retrieval: Citrate pH 6 HIER, heat-mediated (datasheet PB9442). Validated IHC antibody: PB9442 at 0.5-1μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Adrenal gland (Glandular cells); negative None in HPA (detected in all 44 tissues); use no-primary + isotype controls. IHC workflow; specimen preparation unspecified. Protocol steps: 1. Sample: Paraffin-embedded human mammary cancer tissue; fixative not specified (datasheet PB9442); 2. Fixation: Image fixative and duration unreported (datasheet PB9442); 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: Citrate pH 6 , 20 min (datasheet PB9442); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet PB9442); 8. Primary antibody: Rabbit anti-SOD2, 0.5-1μg/ml (datasheet PB9442); 9. Primary incubation: Overnight at 4 °C (datasheet PB9442). Watch for: Fixation: Keep fixation consistent across paraffin sections (standard IHC practice; not target-specific); Caveat: Staining and RNA show medium consistency; restaining pending (HPA tissue IHC); Isoform / epitope: 4 isoforms; chain 25–222; epitope impact unknown (UniProt); Regulation: No expression regulator annotated (UniProt). Evidence: UniProt P04179, HPA tissue IHC · Supported, HPA ICC-IF · mitochondria., Datasheet PB9442, PMC11481372, PMC5955150. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/SOD2/immunohistochemistry-ihc-guide.