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PPL / Periplakin · IHC design guide
Design Immunohistochemistry for PPL
Plan PPL IHC in paraffin sections using membranous squamous epithelial staining and kidney collecting ducts as a high staining control (HPA tissue IHC). The guide covers fixation, the catalog antibody’s 2–5 μg/ml IHC range (datasheet A02098-1), chromogenic detection and staining interpretation.
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
PPL 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 | Membranous in squamous epithelium (HPA tissue IHC) | |
| Staining pattern | Membranous staining of squamous epithelial cells (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A02098-1) | |
| Positive control | Kidney+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 | Collecting ducts also stain strongly (HPA tissue IHC) | |
| Regulation | Enhanced in cervix, esophagus, vagina (HPA tissue RNA) | |
| Isoform / epitope | 0 isoforms; no cleavage or transmembrane segment for epitope mapping (UniProt) |
Section 1
Recommended PPL IHC & IF Protocols
The catalog antibody’s IHC-P protocol is complemented by published PPL staining methods for cryostat sections, human esophageal carcinoma, and mouse liver (PMC3195110; PMC4380967; PMC12198045).
| Sample | Paraffin-embedded human lung cancer tissue; fixative not specified (datasheet A02098-1) |
| Fixation | Image fixative and duration unreported (datasheet A02098-1); 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 A02098-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A02098-1) |
| Primary antibody | Rabbit anti-PPL, 2-5 μg/ml (datasheet A02098-1) |
| Primary incubation | Overnight at 4 °C (datasheet A02098-1) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet A02098-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | PPL-positive staining in collecting ducts of kidney (HPA tissue IHC: High). HPA tissue profile: Membranous expression in squamous epithelium. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA pH 8.0 retrieval for the catalog antibody (datasheet A02098-1); the published esophageal carcinoma method used autoclaved citrate instead (PMC4380967).
Section 2
What Is the Expected PPL Staining Pattern?
Expect PPL chiefly along epithelial cell borders, especially in squamous epithelium (HPA: tissue IHC profile). This fits its desmosomal, lateral membrane and cytoskeletal localization despite having no transmembrane segment (UniProt O60437: localization and topology). HPA rates tissue IHC reliability Enhanced, while reporting only medium consistency between staining and RNA expression (HPA: tissue IHC reliability). Judge a section by its cell types and staining pattern together.
| Distinct border staining in esophageal squamous epithelial cells, with moderate signal (HPA: Esophagus, Medium). | This matches the reported membranous squamous pattern (HPA: tissue IHC profile). A border-associated signal is also consistent with PPL at desmosomes and the lateral membrane (UniProt O60437: localization). Assess the stained cells against neighboring cells rather than treating every brown area as equivalent. |
| Strong staining in kidney collecting ducts (HPA: Kidney collecting ducts, High). | This is a useful second positive pattern because HPA reports a different epithelial cell population at a higher level (HPA: Kidney collecting ducts, High). Its presence supports detection, but intensity alone cannot establish specificity; check that staining follows the expected cells and compartment. |
| Predominantly nuclear staining in a squamous epithelial IHC section. | Treat this as discordant with the reported membranous tissue pattern (HPA: tissue IHC profile). UniProt also lists junctional, membrane and cytoskeletal locations (UniProt O60437: localization). Recheck morphology and controls before scoring it as PPL; the uncertain nucleoplasmic IF annotation does not establish a dominant nuclear IHC pattern (HPA: subcellular ICC-IF). |
| Prominent staining of adipocytes or bone marrow hematopoietic cells. | HPA reports PPL as not detected in those cells (HPA: Adipose tissue; Bone marrow). Consider antibody cross-reactivity or endogenous detection activity, particularly if the color persists without primary antibody (general IHC practice). Review control sections and avoid calling those cells positive on color alone. |
| Hazy color across cells and surrounding tissue, or no signal in an expected positive section. | Diffuse color obscures the cell-border pattern and may reflect background from blocking, washes or detection chemistry (general IHC practice). No signal in esophageal squamous cells or kidney collecting ducts conflicts with HPA observations (HPA: Esophagus, Medium; Kidney collecting ducts, High), but does not by itself identify the failed step. |
💡Expected PPL appearanceCall a positive result when epithelial cell borders are clearly stained—moderately in esophageal squamous cells or strongly in kidney collecting ducts (HPA: tissue IHC); dominant nuclear color or widespread color in HPA-undetected cells is suspect (HPA: tissue IHC; subcellular ICC-IF).
| Choice of tissue and cell population | HPA reports medium staining in esophageal squamous cells and high staining in kidney collecting ducts (HPA: tissue IHC). It reports adipocytes and bone marrow hematopoietic cells as not detected (HPA: tissue IHC). Select and score the named cell population; a whole-section average can hide that distinction. |
| Compartment and molecular topology | PPL is assigned to desmosomes, lateral membrane and cytoskeleton, and has no transmembrane segment (UniProt O60437: localization and topology). Thus border-associated staining is plausible without assuming that the protein spans the membrane. HPA's tissue IHC summary specifically describes membranous staining in squamous epithelium (HPA: tissue IHC profile). |
| Antibody validation and agreement | Both listed antibodies have Enhanced IHC status (HPA: HPA042550; HPA059859). HPA defines this status through agreement between independent antibodies or orthogonal data, while its tissue summary reports medium agreement with RNA expression (HPA: antibody validation; tissue reliability). Use the reported pattern as a benchmark, not proof that every stained structure is specific. |
| Antigen retrieval and epitope | No antibody epitope or PPL-specific retrieval condition is provided in these payloads. Retrieval conditions can be compared using a positive tissue and a negative control as a general paraffin-IHC optimization step (general IHC practice). Do not infer a preferred retrieval method or fixation sensitivity from HPA staining levels or UniProt topology. |
| Detection background | Chromogenic signal can arise from endogenous detection activity or nonspecific reagent binding (general IHC practice). A no-primary control helps distinguish such color from antibody-dependent staining (general IHC practice). Evaluate background in the same tissue and cell population used for the PPL call. |
| Processing and modification | UniProt lists a single PPL chain, no signal peptide or propeptide, and several phosphoserines (UniProt O60437: processing and modified residues). These annotations provide no evidence here that shedding, a particular phosphorylation state or fixation changes this IHC pattern. Do not use them to explain an absent signal without additional evidence. |
| Situation | Likely cause | Next action |
|---|---|---|
| Esophageal squamous cells lack the expected border signal (HPA: Esophagus, Medium). | The negative result could reflect staining workflow failure or a sample difference; HPA's reported level does not identify the cause. | Check tissue morphology, the control slide and detection reagents; then compare retrieval and antibody conditions on the same expected positive tissue (general IHC practice). Record which step restores a cell-border pattern. |
| Kidney collecting ducts are weak or unstained despite a valid positive control (HPA: Kidney collecting ducts, High). | The observed section may differ from HPA's reported high staining, or the local staining conditions may limit detection; the payloads do not establish a PPL-specific fixation effect. | Verify that collecting ducts are present and identifiable, then assess antibody concentration and detection conditions with matched controls (general IHC practice). Do not score unrelated kidney cells as the expected positive population. |
| Brown color fills the section and cell borders cannot be resolved. | Nonspecific binding or detection background may be obscuring the membranous pattern (general IHC practice; HPA: tissue IHC profile). | Inspect a no-primary control, review blocking and washes, and reduce detection intensity if background persists (general IHC practice). Reassess only after cell boundaries are visible. |
| Adipocytes or hematopoietic cells stain strongly (HPA: both cell types Not detected). | Cross-reactivity or endogenous detection activity is possible; positive chromogen alone cannot distinguish them (general IHC practice). | Compare the suspect cells with a no-primary control and the expected epithelial pattern. If the color is antibody-dependent, assess specificity with an independent validated antibody where available (HPA: two Enhanced IHC antibodies). |
| Nuclear staining dominates the epithelial IHC result. | This differs from HPA's membranous squamous IHC profile; HPA's nucleoplasmic ICC-IF annotation is marked uncertain (HPA: tissue IHC; subcellular ICC-IF). | Check counterstain interpretation and no-primary staining, then compare with an expected positive section and an independent antibody if available (general IHC practice; HPA: antibody validation). Do not score nuclear dominance as the established tissue pattern. |
| Q: Should an IF/ICC image be interpreted by the paraffin-IHC pattern? | HPA reports plasma membrane, cytosol and basal body as uncertain main ICC-IF locations, plus uncertain nucleoplasm (HPA: subcellular ICC-IF). Its IHC and ICC assessments also differ for HPA042550 (HPA: antibody validation). | A: Interpret IF/ICC with its own controls and guide. Use this section's membranous squamous pattern for tissue IHC (HPA: tissue IHC profile); do not treat the uncertain IF locations as an IHC protocol or definitive IHC positives. |
Experiment evidence
IHC & IF images showing PPL staining
A02098-1 · IHCIHC analysis of Periplakin using anti-Periplakin antibody (A02098-1). Periplakin was detected in a paraffin-embedded section of human lung c
A02098-1 · IHCIHC analysis of Periplakin using anti-Periplakin antibody (A02098-1). Periplakin was detected in a paraffin-embedded section of human oesoph
A02098-1 · IFIF analysis of Periplakin using anti-Periplakin antibody (A02098-1). Periplakin was detected in immunocytochemical section of A431 cells. En
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000118898-PPL/tissue/cerebral+cortex#imid_18868987
HPA · EsophagusHuman Protein Atlas IHC, Esophagus. Source: https://www.proteinatlas.org/ENSG00000118898-PPL/tissue/esophagus#imid_18868967
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000118898-PPL/tissue/colon#imid_18872379
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000118898-PPL/tissue/liver#imid_18872372
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA042550; green = PPL, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA042550; green = PPL, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for PPL IHC & IF
🧪Run kidney first: collecting duct cells should stain strongly (HPA: High in collecting ducts). Use adrenal gland glandular cells as the negative tissue (HPA: Not detected); on the kidney slide, cells outside collecting ducts should show only counterstain or background where they lack PPL expression, but validate their negative status before scoring them as internal controls (HPA: collecting duct result; standard IHC practice).
Positive control tissue: Kidney (Collecting ducts, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show PPL in A-431, SiHa, U2OS, ASC52telo, RPTEC/TERT1, hTERT-RPE1 (serum starved), with annotated localisation: Plasma membrane (uncertain), Basal body (uncertain), Cytosol (uncertain) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control, a species- and class-matched rabbit IgG isotype control, and a PPL knockout specimen or validated peptide-block control if available (hero caption: rabbit primary; standard IHC practice). For chromogenic kidney sections, quench endogenous peroxidase and block endogenous biotin when using avidin–biotin detection, or use a biotin-free detection system (hero caption: SABC/DAB; standard IHC practice).
⚠️Feasibility: No target-specific fixation window or fixation effect is reported, and the selected A02098-1 paraffin-section caption leaves the fixative unreported. That caption uses heat retrieval in EDTA at pH 8.0, but does not establish that retrieval is required; compare retrieved and unretrieved sections (hero IHC caption; standard IHC practice). Frozen sections or IF cannot be judged easier from these data, and endogenous biotin in renal tubules can confound avidin–biotin staining (standard IHC practice).
HPA tissue IHC evidence for PPL
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — 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 |
|---|---|---|---|---|
| Kidney | Collecting ducts | High | Protein (IHC) | HPA → |
| Breast | Glandular cells | Medium | Protein (IHC) | HPA → |
| Bronchus | Respiratory epithelial cells | Medium | Protein (IHC) | HPA → |
| Cervix | Glandular cells | Medium | Protein (IHC) | HPA → |
| Endometrium | Glandular cells | Low | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Adrenal gland | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Appendix | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Bone marrow | Hematopoietic cells | Not detected | Protein (IHC) | HPA → |
| Caudate | Glial cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced PPL IHC Tips
These PPL troubleshooting answers focus on chromogenic IHC in paraffin sections, with one entry for exploratory IF comparison.
How should I adjust retrieval if PPL staining is weak?
Start with heat-mediated retrieval in EDTA at pH 8.0 for paraffin sections (datasheet A02098-1). The selected image used this retrieval before an overnight incubation at 4°C with 2 μg/ml catalog antibody (caption A02098-1). If staining is weak, compare retrieval duration on adjacent sections while keeping antibody concentration, detection and imaging conditions fixed (standard IHC practice). Include a tissue region expected to stain and inspect morphology after heating, since excessive retrieval can damage sections and make staining hard to score (HPA tissue IHC; standard IHC practice). Record each retrieval condition alongside its control so a brighter result can be judged against any increase in background (standard IHC practice).
Could fixation explain inconsistent PPL staining between paraffin blocks?
Target-specific fixation sensitivity for PPL is unknown from the supplied evidence; the selected paraffin-section caption does not state a fixative (caption A02098-1). Compare blocks only after recording their actual fixative, fixation duration and processing history, because these variables can affect antigen access in routine IHC (standard IHC practice). Keep EDTA retrieval at pH 8.0 and the staining run consistent while assessing that variation (datasheet A02098-1; standard IHC practice). If available, stain adjacent sections from differently processed blocks in the same run and compare an expected positive epithelial compartment with background (UniProt O60437 tissue specificity; standard IHC practice). Do not assign a PPL-specific fixation effect without a direct comparison (standard IHC practice).
Should PPL staining be membranous or cytoplasmic in tissue sections?
Assess cell borders and cytoplasm separately: PPL is associated with desmosomes, lateral membrane and cytoskeleton (UniProt O60437 subcellular location). Membranous staining in squamous epithelium is reported in tissue IHC, while the listed tissues show different expression levels by cell type (HPA tissue IHC). A diffuse cytoplasmic signal can be considered alongside border staining, but score it separately and check its distribution against controls (UniProt O60437 subcellular location; standard IHC practice). Do not treat nuclear-only DAB staining as the expected tissue pattern on this evidence; the additional nucleoplasmic IF assignment is uncertain (HPA subcellular). Examine intact epithelial areas at the same magnification before comparing compartments across sections (standard IHC practice).
How can epitope uncertainty affect PPL IHC interpretation?
The supplied record lists 0 isoforms and a single PPL chain spanning residues 1–1756 (UniProt O60437). It also places an SH3 domain at residues 399–455 and lists several phosphoserines, but the catalog antibody's binding site is not supplied (UniProt O60437; supplied catalog evidence). Consequently, a change in staining cannot be assigned to a particular domain, modification or isoform from these sections alone (standard IHC interpretation). When comparing conditions, hold retrieval at EDTA pH 8.0 and use matched controls before considering epitope access as an explanation (datasheet A02098-1; standard IHC practice). Report the antibody and staining conditions with any compartment-specific finding so it can be reproduced (standard IHC practice).
How should I examine PPL localisation by multiplex IF?
For an exploratory IF comparison, pair PPL with an epithelial marker to identify the expected cell population, then inspect cell borders and cytoplasm separately (UniProt O60437 tissue specificity and subcellular location; standard IF practice). Choose a far-red channel for a weak signal where tissue autofluorescence interferes with shorter wavelengths, and include single-channel controls to check bleed-through (standard IF practice). PPL has no transmembrane segment, while the antibody epitope is unspecified, so compare gentle permeabilisation conditions before interpreting loss of internal or junctional signal (UniProt O60437 topology; supplied catalog evidence; standard IF practice). HPA lists ICC/IF images in several cell lines, but those images do not establish IF performance for SKU A02098-1 (HPA subcellular; supplied catalog evidence).
What should I check when PPL DAB staining has high background?
The selected IHC image used 10% goat serum blocking, a biotinylated secondary, streptavidin-biotin detection and DAB (caption A02098-1). Run a primary-omission control and check whether signal persists in the same tissue structures; residual colour can indicate detection-system background (standard IHC practice). Check the peroxidase block for a DAB workflow, and consider endogenous biotin when using a biotin-based system (standard IHC practice; caption A02098-1). If controls are clean but staining is widespread, titrate the primary below the caption's 2 μg/ml starting condition and compare matched sections (caption A02098-1; standard IHC practice). Preserve a clearly interpretable epithelial positive area while reducing background (UniProt O60437 tissue specificity; standard IHC practice).
How should I quantify PPL staining across paraffin sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and compartment before scoring, because PPL has reported membranous and cytoplasmic locations (UniProt O60437 subcellular location). For epithelial staining, record the percentage of positive cells and an intensity score, or calculate an H-score from intensity-weighted percentages on a 0–300 scale (standard IHC practice). Normalise cell counts to the number of evaluable epithelial cells, or positive-area measurements to evaluable epithelial area in mm², rather than whole-section area (standard IHC practice). Exclude folds, necrosis and section edges using the same criteria across samples, then score matched regions without changing thresholds between slides (standard IHC practice). Report membrane and cytoplasm results separately so their combined value does not hide a localisation shift (UniProt O60437 subcellular location; standard IHC practice).
How can I distinguish convincing PPL staining from artefact?
A convincing result follows epithelial cell borders, potentially with cytoplasmic staining, in an appropriate cell population (HPA tissue IHC; UniProt O60437 subcellular location and tissue specificity). Compare that pattern with the primary-omission control and with an intact region expected to express PPL before calling a sample negative (HPA tissue IHC; standard IHC practice). Be cautious with nuclear-only colour, staining confined to section edges or necrosis, and signal that persists without primary antibody (HPA subcellular; standard IHC practice). For this DAB workflow, persistent colour in the omission control warrants checking endogenous peroxidase and biotin-related detection background (caption A02098-1; standard IHC practice). Document the stained compartment and cell type, since whole-section positivity alone cannot resolve those artefacts (standard IHC practice).
Boster reagents
Best PPL / Periplakin IHC Antibodies
A02098-1 has IHC images from human paraffin sections and IF data from A431 cells; its listed reactivity includes human, mouse and rat (catalog applications/reactivity; A02098-1 image captions).
Real IHC data
Anti-Periplakin/PPL Antibody ®
Cat # A02098-1
A02098-1 will render with its own IHC figure from a human lung cancer paraffin section (A02098-1 IHC figure caption). Additional IHC captions show human oesophagus squama cancer and tonsil sections, while its IF caption shows A431 cells (A02098-1 image captions).
Which to pick: Choose A02098-1 for paraffin-section IHC: its figure documents EDTA retrieval at pH 8.0 and primary antibody at 2 μg/ml (A02098-1 IHC figure caption). The same SKU is listed for IF/ICC, with IF shown in A431 cells at 5 μg/ml (catalog applications; A02098-1 IF caption). For cross-species work, A02098-1 lists human, mouse and rat reactivity, but the supplied IHC captions document only human sections; the IHC fixative is unreported (catalog reactivity; A02098-1 IHC captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry O60437 (PEPL_HUMAN, Periplakin).
- Human Protein Atlas. PPL tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. PPL subcellular location (ICC-IF): Mainly localized to the plasma membrane, cytosol and basal body. In addition localized to the nucleoplasm..
- Human Protein Atlas. PPL antibody validation summary (2 antibodies).
- Adhesion molecule periplakin is involved in cellular movement and attachment in pharyngeal squamous cancer cells. BMC cell biology 2011 — PMC3195110.
- Cholestasis induces reversible accumulation of periplakin in mouse liver. BMC gastroenterology 2013 — PMC3716950.
- Aberrant DNA hypermethylation reduces the expression of the desmosome-related molecule periplakin in esophageal squamous cell carcinoma. Cancer medicine 2015 — PMC4380967.
- Periplakin Attenuates Liver Fibrosis via Reprogramming CD44(Low) Cells into CD44(High) Liver Progenitor Cells. Cellular and molecular gastroenterology and hepatology 2025 — PMC12198045.
- PubMed PMID:9412476 — UniProt-cited evidence.
- PubMed PMID:9521878 — UniProt-cited evidence.
- PubMed PMID:10051401 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for PPL (Periplakin). Expected localisation Membranous in squamous epithelium (HPA tissue IHC). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A02098-1). Validated IHC antibody: A02098-1 at 2-5 μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Kidney (Collecting ducts); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human lung cancer tissue; fixative not specified (datasheet A02098-1); 2. Fixation: Image fixative and duration unreported (datasheet A02098-1); 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 A02098-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A02098-1); 8. Primary antibody: Rabbit anti-PPL, 2-5 μg/ml (datasheet A02098-1); 9. Primary incubation: Overnight at 4 °C (datasheet A02098-1). Watch for: Fixation: Keep fixation consistent across sections (standard IHC practice; not target-specific); Caveat: Collecting ducts also stain strongly (HPA tissue IHC); Isoform / epitope: 0 isoforms; no cleavage or transmembrane segment for epitope mapping (UniProt); Regulation: Enhanced in cervix, esophagus, vagina (HPA tissue RNA). Evidence: UniProt O60437, HPA tissue IHC · Enhanced, HPA ICC-IF · Mainly localized to the plasma membrane, cytosol and basal body. In…, Datasheet A02098-1, PMC3195110, PMC4380967. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/PPL/immunohistochemistry-ihc-guide.