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SERPINB5 / Serpin B5 · IHC design guide
Design Immunohistochemistry for SERPINB5
Plan SERPINB5 paraffin-section IHC using esophageal squamous cells as a positive control and adipocytes as a negative control (HPA tissue IHC). This guide covers fixation consistency, chromogenic detection, and scoring of the variable cytoplasmic staining pattern (standard IHC practice; HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
SERPINB5 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 tissue staining (HPA tissue IHC); secreted protein (UniProt) | |
| Staining pattern | Variable cytoplasmic staining, strongest in squamous epithelia (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet M03409) | |
| Positive control | Esophagus+4 more · see all | |
| Negative control | Adipose tissue+4 more · see all |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep fixation consistent across sections. (standard IHC practice; not target-specific) | |
| Caveat | Secretion may complicate interpretation of cytoplasmic staining (UniProt; HPA tissue IHC) | |
| Regulation | Highest staining in squamous epithelia and gut (HPA tissue IHC) | |
| Isoform / epitope | 2 isoforms; epitope and compartment effects unreported (UniProt) |
Section 1
Recommended SERPINB5 IHC & IF Protocols
The catalog antibody uses heat-mediated EDTA pH 8.0 retrieval (datasheet M03409). Published SERPINB5 IHC methods from 3 articles follow (PMC12921336; PMC10425712; PMC6995195).
| Sample | Paraffin-embedded human tonsil tissue; fixative not specified (datasheet M03409) |
| Fixation | Image fixative and duration unreported (datasheet M03409); 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 M03409); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet M03409) |
| Primary antibody | Mouse monoclonal (clone 7G4E1) anti-SERPINB5, 2 μg/ml (datasheet M03409) |
| Primary incubation | Overnight at 4 °C (datasheet M03409) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet M03409) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | SERPINB5-positive staining in squamous epithelial cells of esophagus (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression with varying intensity in most tissues, most abundant in squamous epithelia and the gastrointestinal tract. No signal in the no-primary control. |
💡Decision noteStart with EDTA pH 8.0 for the catalog antibody (datasheet M03409). Boiled 0.1 M sodium citrate is a published alternative for stomach sections (PMC10425712).
Section 2
What Is the Expected SERPINB5 Staining Pattern?
For IHC of paraffin sections, expect predominantly cytoplasmic SERPINB5 staining in epithelial cells, especially esophageal squamous cells, skin basal cells and bladder urothelial cells (HPA: High in each). UniProt describes SERPINB5 as secreted, with no transmembrane segment (UniProt P36952: subcellular location and topology). Treat the tissue pattern as a guide: HPA rates its IHC reliability Enhanced but reports medium agreement with RNA data and pending external verification (HPA: tissue IHC).
| Strong cytoplasmic staining in esophageal squamous cells, skin basal cells or bladder urothelial cells. | This matches the most useful positive tissue examples (HPA: High in these cells; cytoplasmic tissue profile). Compare staining within the named cell population, rather than assigning one score to the whole section (general IHC practice). |
| Predominantly nuclear or sharply membrane-restricted staining, with little cytoplasmic signal. | This departs from the reported tissue IHC pattern (HPA: cytoplasmic tissue profile). Review morphology and controls before calling it specific; UniProt reports a secreted protein without a transmembrane segment, so membrane restriction needs independent support (UniProt P36952: location and topology). |
| Strong staining chiefly in adipocytes, smooth muscle cells or lymph-node germinal-center cells. | Those named populations were not detected in the HPA tissue examples (HPA: adipose tissue, smooth muscle, lymph node). Consider antibody cross-reactivity or endogenous detection activity, then compare with a known-positive epithelial section and appropriate detection controls (general IHC practice). |
| Diffuse color across epithelium, stroma and blank areas, with no clear cell boundaries. | That distribution cannot be read as a cell-specific SERPINB5 pattern (HPA: cytoplasmic tissue profile). Background may arise from detection chemistry, inadequate blocking or excess antibody (general IHC practice); check the negative detection control before scoring. |
| No convincing signal in a section containing esophageal squamous epithelium. | HPA reports High staining in those cells, so this is a failed positive-control result until the staining run is checked (HPA: Esophagus, High). Review tissue preservation, retrieval, antibody and detection steps as general IHC variables; no SERPINB5-specific fixation sensitivity is supplied (general IHC practice). |
💡Expected SERPINB5 appearanceCall a positive result when epithelial cells show clear cytoplasmic staining, strongest in HPA High examples; isolated nuclear staining or color outside identifiable cells is suspect (HPA: tissue IHC profile; general IHC practice).
| Tissue and cell choice (HPA: tissue IHC) | Esophagus squamous cells, skin basal cells and bladder urothelial cells are High; cervical, tonsillar and vaginal squamous cells are Medium (HPA: tissue IHC). Choose a High example for the run control; a Medium example offers less room to detect a weak run (general IHC practice). |
| Cellular compartment (HPA: tissue IHC; UniProt P36952) | HPA tissue IHC describes cytoplasmic staining; UniProt lists SERPINB5 as secreted and lacking a transmembrane segment (HPA: tissue profile; UniProt P36952: location and topology). The annotations differ in emphasis, so require a convincing tissue and cell pattern before interpreting extracellular color. |
| Evidence strength (HPA: tissue IHC; HPA: antibodies) | HPA calls tissue IHC Enhanced and lists 4 antibodies with Enhanced IHC status, yet describes only medium staining–RNA consistency and pending external verification (HPA: reliability and antibody validation). Use the pattern as a reference, while retaining run controls for each experiment (general IHC practice). |
| Isoforms and modification (UniProt P36952) | UniProt lists 2 isoforms and 4 glycosylation sites, at residues 99, 133, 188 and 361 (UniProt P36952: isoforms and glycosylation). These annotations alone do not identify the antibody epitope or predict a different staining pattern; assess any proposed variant-specific interpretation separately. |
| IF/ICC Q: What pattern should I compare? (HPA: subcellular ICC-IF) | A: HPA reports SERPINB5 mainly in vesicles in ICC-IF, with a supported vesicle location (HPA: subcellular ICC-IF). That is an IF reference, while the paraffin-section IHC comparison remains the HPA cytoplasmic tissue pattern (HPA: tissue IHC). |
| Situation | Likely cause | Next action |
|---|---|---|
| Known-positive esophageal epithelium is blank. | The expected High cell population is missing from the readout (HPA: Esophagus, High); the run or tissue may have failed (general IHC practice). | Confirm the squamous cells are present; review retrieval, antibody dilution and detection against the run controls (general IHC practice). No target-specific retrieval or fixation response is established here. |
| All tissue compartments have a pale, even deposit. | Uniform color obscures the expected cytoplasmic epithelial contrast (HPA: tissue IHC profile); nonspecific detection background is possible (general IHC practice). | Inspect a no-primary detection control, then review blocking, washes and antibody concentration under the standard IHC workflow (general IHC practice). |
| Signal appears mainly in nuclei or along cell borders. | The compartment differs from HPA's cytoplasmic tissue profile; a border-only pattern is also unsupported by UniProt's lack of a transmembrane segment (HPA: tissue IHC; UniProt P36952: topology). | Check section morphology and detection controls, then compare with a known-positive epithelial section before assigning SERPINB5 specificity (general IHC practice; HPA: High epithelial examples). |
| Adipocytes or smooth muscle stain as strongly as the epithelial control. | HPA reports SERPINB5 as not detected in those named cells; cross-reactivity or endogenous detection activity should be considered (HPA: adipose tissue and smooth muscle). | Compare those cells with a High epithelial control and a no-primary control; review blocking and detection chemistry if the controls show color (HPA: High epithelial examples; general IHC practice). |
| A low-expression tissue looks negative. | HPA lists only Low staining in lung alveolar cells and bronchial respiratory cells, so a weak result is hard to distinguish from a missed signal (HPA: Lung and Bronchus, Low). | Judge run performance in a High epithelial example first; interpret the low-level tissue only after its cell type and local background are clear (HPA: High epithelial examples; general IHC practice). |
| IHC looks broadly cytoplasmic, but IF looks punctate. | The two HPA readouts use different pattern descriptions: cytoplasmic tissue IHC and mainly vesicular ICC-IF (HPA: tissue IHC; HPA: subcellular ICC-IF). | Score each assay against its own HPA reference and its own controls; do not require paraffin-section chromogenic staining to resolve individual vesicles (HPA: tissue IHC and subcellular ICC-IF; general IHC practice). |
Experiment evidence
IHC & IF images showing SERPINB5 staining
M03409 · IHCIHC analysis of MASPIN using anti-MASPIN antibody (M03409). MASPIN was detected in a paraffin-embedded section of human tonsil tissue. Heat
M03409 · IHCIHC analysis of MASPIN using anti-MASPIN antibody (M03409). MASPIN was detected in a paraffin-embedded section of human laryngeal squamous c
PB9356 · IHCIHC analysis of MASPIN/SERPINB5 using anti-MASPIN/SERPINB5 antibody (PB9356). MASPIN/SERPINB5 was detected in a paraffin-embedded section of
PB9356 · IHCIHC analysis of MASPIN/SERPINB5 using anti-MASPIN/SERPINB5 antibody (PB9356). MASPIN/SERPINB5 was detected in a paraffin-embedded section of
PB9356 · IFIF analysis of MASPIN/SERPINB5 using anti-MASPIN/SERPINB5 antibody (PB9356). MASPIN/SERPINB5 was detected in an immunocytochemical section o
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000206075-SERPINB5/tissue/cerebral+cortex#imid_2654404
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000206075-SERPINB5/tissue/colon#imid_2635602
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000206075-SERPINB5/tissue/liver#imid_2635603
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000206075-SERPINB5/tissue/kidney#imid_2635596
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA019025; green = SERPINB5, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA019025; green = SERPINB5, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for SERPINB5 IHC & IF
🧪Run esophagus first and require staining in its squamous epithelial cells (HPA: High in esophageal squamous epithelial cells); use adipose tissue as the negative tissue (HPA: Not detected in adipocytes). On the esophagus slide, assess adjacent non-epithelial cells as internal background, without assuming they are confirmed SERPINB5-negative (HPA: High is assigned to squamous epithelial cells).
Positive control tissue: Esophagus (Squamous epithelial cells, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show SERPINB5 in A-431, PC-3, U2OS, with annotated localisation: Vesicles (supported) (HPA subcellular).
Technical controls: Include no-primary (secondary-only) and concentration-matched mouse IgG isotype controls, plus SERPINB5 knockout tissue or cells as a biological negative (selected M03409 caption: mouse primary antibody). Quench endogenous peroxidase and check for nonspecific DAB deposition in the esophagus section (selected M03409 caption: peroxidase detection with DAB).
⚠️Feasibility: No target-specific fixation window or fixation effect is reported in the supplied evidence, and the selected paraffin-section caption leaves the fixative unreported (selected M03409 caption: fixative not stated). Heat retrieval in EDTA at pH 8.0 is a documented starting condition, but its necessity has not been established here (selected M03409 caption: heat-mediated EDTA retrieval). Neither frozen sections nor IF are established as easier; assess staining in viable squamous epithelium separately from surface debris that could retain chromogen (HPA: High in esophageal squamous epithelial cells; selected M03409 caption: DAB detection).
HPA tissue IHC evidence for SERPINB5
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — 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 |
|---|---|---|---|---|
| Esophagus | Squamous epithelial cells | High | Protein (IHC) | HPA → |
| Skin | Cells in basal layer | High | Protein (IHC) | HPA → |
| Urinary bladder | Urothelial cells | High | Protein (IHC) | HPA → |
| Cervix | Squamous epithelial cells | Medium | Protein (IHC) | HPA → |
| Tonsil | Squamous epithelial cells | Medium | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Bone marrow | Hematopoietic cells | Not detected | Protein (IHC) | HPA → |
| Caudate | Glial cells | Not detected | Protein (IHC) | HPA → |
| Cerebellum | Cells in granular layer | Not detected | Protein (IHC) | HPA → |
| Hippocampus | Glial cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced SERPINB5 IHC Tips
Troubleshoot SERPINB5 staining in paraffin sections by checking retrieval, cellular distribution, controls, and scoring against documented tissue patterns.
Which retrieval condition should I start with for SERPINB5 paraffin-section IHC?
Start with heat-mediated retrieval in EDTA at pH 8.0 for paraffin sections (datasheet M03409). The selected tonsil image used this retrieval, followed by a 10% goat serum block and 2 μg/ml primary antibody overnight at 4°C (IHC caption M03409). If staining is weak, compare longer heating or a citrate-buffer fallback on adjacent sections while keeping detection conditions constant; neither change is a validated SERPINB5 condition (standard IHC practice). Use tonsil squamous epithelium as a reference for expected medium staining (HPA: Tonsil squamous epithelial cells, Medium). Judge improvement by cell-specific cytoplasmic signal and preserved tissue morphology, rather than overall DAB darkness (HPA: cytoplasmic tissue profile; standard IHC practice).
How should I troubleshoot weak staining when the specimen fixation history varies?
The selected paraffin-section caption does not state a fixative, so target-specific fixation sensitivity is unknown (IHC caption M03409). Record the fixative and fixation duration for each specimen, then compare sections processed with the same retrieval and detection conditions (standard IHC practice). Keep the documented EDTA pH 8.0 retrieval and 2 μg/ml overnight primary incubation as starting conditions when assessing a fixation difference (IHC caption M03409). Include a section with expected epithelial staining in each run, such as tonsil squamous epithelium (HPA: Tonsil squamous epithelial cells, Medium). Do not attribute a weak result to a SERPINB5-specific fixation effect without a direct comparison under controlled processing conditions (standard IHC practice).
Should SERPINB5 appear in cytoplasm, vesicles, or extracellular material?
Score cytoplasmic staining in the relevant epithelial cells first, because that is the predominant tissue-IHC pattern (HPA: cytoplasmic expression in most tissues). Vesicular staining is also biologically plausible: the supported subcellular location is vesicles in ICC/IF images (HPA: Vesicles, supported). UniProt annotates SERPINB5 as secreted into the extracellular space and reports no transmembrane segment, so a crisp plasma-membrane outline is not the expected defining pattern (UniProt P36952: subcellular location and topology). Examine adjacent epithelial and stromal areas separately before calling diffuse extracellular DAB a positive cellular result (standard IHC practice). Confirm uncertain localisation against the no-primary control and the section morphology, including the counterstain (standard IHC practice).
Could splice variants or glycosylation explain inconsistent SERPINB5 staining?
SERPINB5 has 2 annotated isoforms and 4 glycosylation sites, at residues 99, 133, 188, and 361 (UniProt P36952: isoforms and glycosylation). The supplied evidence does not map the catalog antibody’s epitope, so its recognition of each isoform or glycosylation state cannot be assumed (supplied catalog evidence: epitope unspecified). First verify that retrieval, primary incubation, and tissue processing are comparable across sections (standard IHC practice). The documented IHC starting conditions are EDTA pH 8.0 retrieval and 2 μg/ml primary overnight at 4°C (IHC caption M03409). If discrepancies persist, seek epitope information or compare with an independently validated antibody before assigning an isoform-specific explanation (standard IHC practice).
How can I investigate SERPINB5 localisation with multiplex IF or ICC?
Pair SERPINB5 with a marker that identifies the epithelial cell population being assessed; HPA reports high staining in esophageal squamous epithelial cells and skin basal-layer cells (HPA: Esophagus, High; Skin, High). Select fluorophores after inspecting an unstained section for autofluorescence, using a spectrally separated channel when background is strong (standard IF practice). For intracellular or vesicular epitopes, compare staining with and without gentle permeabilisation; access to an extracellular epitope may differ, and this antibody’s epitope is unspecified (HPA: Vesicles, supported; supplied catalog evidence: epitope unspecified; standard IF practice). Include single-label and secondary-only controls to assess bleed-through and nonspecific fluorescence (standard IF practice). The 2 μg/ml overnight condition comes from chromogenic paraffin IHC and is not an established IF condition (IHC caption M03409).
What controls help distinguish SERPINB5 staining from nonspecific DAB background?
Begin with a no-primary control and inspect whether DAB persists in the same structures; persistent staining points to a detection or tissue-background problem (standard IHC practice). Block endogenous peroxidase before HRP detection and assess endogenous pigment against the counterstained morphology (standard IHC practice). The selected tonsil image used a 10% goat serum block, a peroxidase-conjugated anti-mouse secondary for 30 minutes at 37°C, and DAB development (IHC caption M03409). If background is widespread, check block compatibility, antibody concentration, washing, and chromogen development time on adjacent sections (standard IHC practice). Preserve the epithelial-cell pattern as the criterion for useful signal, since HPA describes predominantly cytoplasmic SERPINB5 tissue staining (HPA: cytoplasmic tissue profile).
How should I score SERPINB5 IHC across specimens with different epithelial content? ⚠ ANSWER MARKED FOR VERIFICATION
Define the epithelial compartment on the counterstain before measuring SERPINB5, because reported expression varies by tissue and cell type (HPA: tissue-IHC profile). Record the percentage of positive epithelial cells and staining intensity, or calculate an H-score from 0–300 using the percentages at each intensity grade (standard IHC scoring practice). Normalize each percentage to evaluable epithelial cells, rather than total section area, and report the number of cells or regions scored (standard IHC scoring practice). Keep thresholds, illumination, DAB development, and region-selection rules consistent across specimens (standard IHC scoring practice). Include a reference section and describe its expected range; tonsil squamous epithelial staining is medium in the supplied tissue profile (HPA: Tonsil squamous epithelial cells, Medium).
When should I question an apparent positive SERPINB5 IHC result?
A convincing result follows the expected cell distribution and predominantly cytoplasmic pattern: HPA reports high staining in esophageal squamous epithelial cells and skin basal-layer cells (HPA: Esophagus, High; Skin, High; cytoplasmic tissue profile). Question equally strong staining in an unexpected cell population, while allowing that tissue expression varies (HPA: tissue-IHC profile). Review section edges and necrotic areas for staining that tracks tissue damage rather than intact cell boundaries (standard IHC practice). Check whether similar DAB appears without primary antibody, which can expose endogenous peroxidase or detection background (standard IHC practice). Interpret weak or discordant patterns cautiously because the tissue-IHC profile has medium consistency with RNA data and awaits external verification (HPA: Enhanced reliability description).
Boster reagents
Best SERPINB5 / Serpin B5 IHC Antibodies
The catalog shows anti-SERPINB5 IHC images from human paraffin sections and mouse colon, plus an IF/ICC image from A431 cells (catalog image captions).
Real IHC data
Anti-MASPIN Antibody ® (monoclonal, 7G4E1)
Cat # M03409
Real IHC data
Anti-MASPIN/SERPINB5 Antibody ®
Cat # PB9356
M03409 has human tonsil and laryngeal squamous cell carcinoma IHC images from paraffin sections (M03409 IHC captions). PB9356 has human colon cancer and mouse colon IHC images from paraffin sections, plus an A431-cell IF/ICC image (PB9356 image captions).
Which to pick: For human tissue IHC, M03409 offers mouse monoclonal clone 7G4E1, with pH 8.0 EDTA retrieval shown in its human tonsil paraffin-section image (catalog: M03409 clone; M03409 IHC caption). Choose PB9356 for IF/ICC or IHC across human and mouse samples: those applications and species are listed, and its own images show A431-cell IF and paraffin-section IHC in both species (catalog: PB9356 applications and reactivity; PB9356 image captions). The fixative is unreported for both IHC images (M03409 and PB9356 IHC captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P36952 (SPB5_HUMAN, Serpin B5).
- Human Protein Atlas. SERPINB5 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. SERPINB5 subcellular location (ICC-IF): Mainly localized to vesicles..
- Human Protein Atlas. SERPINB5 antibody validation summary (4 antibodies).
- M(5)C-driven stabilization of SERPINB5 promotes cervical cancer progression and chemotherapy resistance. Cell death & disease 2026 — PMC12921336.
- SERPINB5 is a novel serum diagnostic biomarker for gastric high-grade intraepithelial neoplasia and plays a role in regulation of macrophage phenotypes. Translational oncology 2023 — PMC10425712.
- TRIM21-SERPINB5 aids GMPS repression to protect nasopharyngeal carcinoma cells from radiation-induced apoptosis. Journal of biomedical science 2020 — PMC6995195.
- BTG2 and SerpinB5, a novel gene pair to evaluate the prognosis of lung adenocarcinoma. Frontiers in immunology 2023 — PMC10064863.
- PubMed PMID:8290962 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
- PubMed PMID:16177791 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for SERPINB5 (Serpin B5). Expected localisation Cytoplasmic tissue staining (HPA tissue IHC); secreted protein (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet M03409). Validated IHC antibody: M03409 at 2 μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Esophagus (Squamous epithelial cells); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human tonsil tissue; fixative not specified (datasheet M03409); 2. Fixation: Image fixative and duration unreported (datasheet M03409); 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 M03409); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet M03409); 8. Primary antibody: Mouse monoclonal (clone 7G4E1) anti-SERPINB5, 2 μg/ml (datasheet M03409); 9. Primary incubation: Overnight at 4 °C (datasheet M03409). Watch for: Fixation: Keep fixation consistent across sections. (standard IHC practice; not target-specific); Caveat: Secretion may complicate interpretation of cytoplasmic staining (UniProt; HPA tissue IHC); Isoform / epitope: 2 isoforms; epitope and compartment effects unreported (UniProt); Regulation: Highest staining in squamous epithelia and gut (HPA tissue IHC). Evidence: UniProt P36952, HPA tissue IHC · Enhanced, HPA ICC-IF · Mainly localized to vesicles., Datasheet M03409, PMC12921336, PMC10425712. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/SERPINB5/immunohistochemistry-ihc-guide.