This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
PPP1R15A / Protein phosphatase 1 regulatory subunit 15A · IHC design guide
Design Immunohistochemistry for PPP1R15A
Plan PPP1R15A paraffin IHC around granular cytoplasmic staining (HPA tissue IHC). The catalog antibody has an IHC dilution range of 2–5 μg/ml (datasheet A02394-2); duodenal glandular cells show high staining and can guide tissue selection (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
PPP1R15A 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 | Granular cytoplasm (HPA tissue IHC); ER/outer mitochondrial membrane expected (UniProt) | |
| Staining pattern | Granular cytoplasmic staining in several tissues (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A02394-2) | |
| Positive control | Duodenum+4 more · see all | |
| Negative control | Cervix+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 | Antibody staining has medium concordance with RNA expression (HPA tissue IHC) | |
| Regulation | Growth arrest and DNA damage inducible (UniProt) | |
| Isoform / epitope | 2 isoforms; check epitope coverage across both (UniProt) |
Section 1
Recommended PPP1R15A IHC & IF Protocols
The catalog antibody’s IHC-P protocol (datasheet A02394-2) is accompanied by a published chromogenic protocol for human lung sections (PMC8566588).
| Sample | Paraffin-embedded human melanom tissue; fixative not specified (datasheet A02394-2) |
| Fixation | Image fixative and duration unreported (datasheet A02394-2); 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 A02394-2); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A02394-2) |
| Primary antibody | Rabbit anti-PPP1R15A, 2-5 μg/ml (datasheet A02394-2) |
| Primary incubation | Overnight at 4 °C (datasheet A02394-2) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet A02394-2) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | PPP1R15A-positive staining in glandular cells of duodenum (HPA tissue IHC: High). HPA tissue profile: Granular cytoplasmic expression in several tissues. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA retrieval at pH 8.0 (datasheet A02394-2); the published lung protocol used a high-pH retrieval buffer (PMC8566588).
Section 2
What Is the Expected PPP1R15A Staining Pattern?
PPP1R15A should appear as granular cytoplasmic staining in several tissues, especially duodenal and prostatic glandular cells (HPA tissue IHC: High; granular cytoplasmic profile). Its membrane associations are with the endoplasmic reticulum and mitochondrial outer membrane, through an N-terminal amphipathic region without an annotated transmembrane segment (UniProt O75807: subcellular location and topology). Treat tissue predictions as guides: HPA rates the IHC evidence Approved, with medium consistency between staining and RNA expression (HPA tissue IHC: reliability).
| Granular cytoplasmic staining in duodenal or prostatic glandular cells, with the cells identifiable on the counterstained section. | This matches the reported compartment and the two listed High cell populations (HPA tissue IHC: granular cytoplasmic profile; High in duodenal and prostatic glandular cells). Compare intensity within the same staining run; HPA levels are reference observations, not a required score for every specimen (HPA tissue IHC: reported levels; general IHC practice). |
| A dominant nuclear or sharply surface-restricted signal replaces cytoplasmic granules. | This conflicts with HPA's tissue pattern and UniProt's cytoplasmic-facing membrane topology (HPA tissue IHC: granular cytoplasmic profile; UniProt O75807: topology). Review morphology and the detection controls before assigning the signal to PPP1R15A (general IHC practice). |
| Strong staining appears in cardiomyocytes or cervical squamous epithelial cells. | HPA reports PPP1R15A as Not detected in those named cells; the result warrants a specificity check, including cross-reactivity or endogenous detection activity (HPA tissue IHC: cardiomyocytes and cervical squamous epithelial cells Not detected; general IHC practice). It does not prove that every cell in either tissue must be negative (HPA tissue IHC: cell-specific observations). |
| Colour spreads across stroma or cell-free areas and obscures cell boundaries. | This is diffuse background rather than the reported granular cytoplasmic pattern (HPA tissue IHC: granular cytoplasmic profile). Assess the negative detection control and the distribution of precipitate before scoring cells (general chromogenic IHC practice). |
| The expected glandular cells show no signal in a duodenum or prostate control section. | An absent signal in cells listed as High makes the run difficult to interpret (HPA tissue IHC: High in duodenal and prostatic glandular cells). Check control tissue preservation, retrieval, antibody and detection steps together; one negative section cannot establish that PPP1R15A is absent from the specimen (general IHC practice). |
💡Expected PPP1R15A appearanceCall a result consistent with PPP1R15A when identifiable duodenal or prostatic glandular cells show clear granular cytoplasmic staining, potentially strong relative to local background (HPA tissue IHC: High; granular cytoplasmic profile); dominant nuclear, surface-only or cell-free staining calls for review (HPA tissue IHC: cytoplasmic profile; general IHC practice).
| Compartment and topology (UniProt O75807: subcellular location and topology). | PPP1R15A associates with endoplasmic reticulum and mitochondrial outer membranes through an N-terminal amphipathic region; its annotated regions face the cytoplasm (UniProt O75807: topology). Interpret membrane-associated granularity within the cytoplasm without requiring a visible organelle outline in chromogenic sections (UniProt O75807: location; general IHC practice). |
| Cell-specific reference pattern (HPA tissue IHC: reported cell levels). | Duodenal and prostatic glandular cells are listed High; appendix, breast and colon glandular cells are listed Medium (HPA tissue IHC: cell levels). Cervical squamous epithelial cells and cardiomyocytes are listed Not detected (HPA tissue IHC: cell levels). Use the named cells when comparing sections, rather than treating an entire organ as uniformly positive or negative (HPA tissue IHC: cell-specific entries). |
| Validation scope (HPA antibodies: HPA020240 and CAB018395; HPA tissue IHC: reliability). | Both listed antibodies have Approved IHC status; the tissue summary notes medium consistency with RNA expression (HPA antibodies: IHC Approved; HPA tissue IHC: reliability). Those ratings support comparison with the observed pattern but do not establish that an unexpected signal is target-specific (HPA tissue IHC: validation summary; general IHC practice). |
| Isoforms and epitope uncertainty (UniProt O75807: isoforms). | UniProt lists two isoforms, but the supplied record gives no antibody epitope or isoform-specific staining evidence (UniProt O75807: isoforms; HPA antibodies: supplied fields). Avoid assigning a staining difference to one isoform without independent evidence (general IHC interpretation practice). |
| IF/ICC Q: Should vesicular fluorescence define the paraffin IHC pattern? (HPA subcellular ICC-IF: vesicles, uncertain). | A: No. HPA calls the ICC-IF location vesicles with uncertain confidence, whereas its tissue IHC profile is granular cytoplasmic (HPA subcellular ICC-IF: uncertain; HPA tissue IHC: profile). Interpret each application against its own evidence (general assay interpretation practice). |
| Situation | Likely cause | Next action |
|---|---|---|
| The positive control lacks staining in duodenal or prostatic glandular cells (HPA tissue IHC: High). | A failed staining step or an unsuitable control section is possible; the HPA level alone does not identify which step failed (HPA tissue IHC: High; general IHC practice). | Target-specific fixation effects are not established by the supplied assay evidence. Verify with a matched IHC source before attributing a result to fixation. |
| The negative detection control develops colour (general chromogenic IHC practice). | Detection reagents or endogenous tissue activity may contribute signal independently of primary-antibody binding (general chromogenic IHC practice). | Check the control and address the relevant endogenous activity within the IHC detection workflow before interpreting cell staining (general chromogenic IHC practice). |
| Staining is widespread and diffuse, obscuring cytoplasmic granules (HPA tissue IHC: granular cytoplasmic profile). | Background from antibody concentration, incomplete blocking or washing may obscure the reported pattern (general IHC practice; HPA tissue IHC: profile). | Compare a matched negative control, then review blocking, washing and the catalog antibody's IHC-P dilution guidance (general IHC practice); no dilution value is supplied here (HPA antibodies: supplied fields). |
| A dominant nuclear or cell-surface pattern appears (HPA tissue IHC: granular cytoplasmic profile). | The compartment conflicts with the tissue profile and cytoplasmic-facing topology, so assignment to PPP1R15A is uncertain (HPA tissue IHC: profile; UniProt O75807: topology). | Confirm cellular boundaries with the counterstain and compare the positive and negative detection controls before scoring (general IHC practice). |
| An HPA-listed Not detected cell population stains strongly (HPA tissue IHC: cardiomyocytes or cervical squamous epithelial cells). | Cross-reactivity or endogenous detection activity is possible, while HPA observations do not establish an absolute biological absence (HPA tissue IHC: cell-specific levels; general IHC practice). | Check the named cell type, inspect the negative detection control and seek independent specificity evidence before reporting a new cell-type pattern (general IHC practice; HPA tissue IHC: cell-specific reference). |
Experiment evidence
IHC & IF images showing PPP1R15A staining
A02394-2 · IHCIHC analysis of GADD34/PPP1R15A using anti-GADD34/PPP1R15A antibody (A02394-2). GADD34/PPP1R15A was detected in a paraffin-embedded section
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000087074-PPP1R15A/tissue/cerebral+cortex#imid_5457464
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000087074-PPP1R15A/tissue/colon#imid_5457390
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000087074-PPP1R15A/tissue/liver#imid_5457391
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000087074-PPP1R15A/tissue/kidney#imid_5457392
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA020240; green = PPP1R15A, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA020240; green = PPP1R15A, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for PPP1R15A IHC & IF
🧪Run duodenum first; its glandular cells should stain (HPA: High in duodenal glandular cells). Use cervix squamous epithelial cells as the negative tissue (HPA: Not detected in cervical squamous epithelial cells); on the duodenum slide, compare glandular staining with adjacent nonglandular cells as an internal background check, without assuming those cells are target negative (HPA: glandular cells are the annotated positive population).
Positive control tissue: Duodenum (Glandular cells, HPA High)
Negative control tissue: Cervix (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show PPP1R15A in A-431, U-251MG, with annotated localisation: Vesicles (uncertain) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control, a rabbit IgG isotype control matched to the primary antibody’s clonality and concentration, and PPP1R15A knockout tissue or cells as a biological negative (selected-SKU caption: rabbit primary; standard IHC control practice). Quench endogenous peroxidase and inspect the no-primary duodenum section for DAB background before interpreting glandular staining (selected-SKU caption: peroxidase and DAB detection; standard IHC practice).
⚠️Feasibility: The selected-SKU caption demonstrates paraffin-section IHC with heat retrieval in EDTA at pH 8.0, but reports no fixative; a PPP1R15A-specific fixation window or fixation effect is unreported (selected-SKU tissue-IHC caption). Retrieval was used in that example, but its necessity has not been established; the supplied evidence does not show whether frozen-section IHC or IF is easier (selected-SKU tissue-IHC caption; HPA: ICC-IF images in A-431 and U-251MG). In duodenum, check for endogenous peroxidase or nonspecific DAB background that could obscure glandular staining (HPA: High in duodenal glandular cells; standard IHC practice).
HPA tissue IHC evidence for PPP1R15A
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Approved — 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 |
|---|---|---|---|---|
| Duodenum | Glandular cells | High | Protein (IHC) | HPA → |
| Prostate | Glandular cells | High | Protein (IHC) | HPA → |
| Appendix | Glandular cells | Medium | Protein (IHC) | HPA → |
| Bone marrow | Hematopoietic cells | Medium | Protein (IHC) | HPA → |
| Breast | Glandular cells | Medium | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Cervix | Squamous epithelial cells | Not detected | Protein (IHC) | HPA → |
| Heart muscle | Cardiomyocytes | Not detected | Protein (IHC) | HPA → |
| Liver | Cholangiocytes | Not detected | Protein (IHC) | HPA → |
| Ovary | Follicle cells | Not detected | Protein (IHC) | HPA → |
| Seminal vesicle | Glandular cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced PPP1R15A IHC Tips
Troubleshoot PPP1R15A staining in paraffin sections by checking retrieval, compartment, controls and cell-level scoring against the supplied IHC evidence.
Which retrieval condition should I try first for PPP1R15A in paraffin sections?
Start with heat-mediated retrieval in EDTA at pH 8.0 for the catalog antibody (datasheet A02394-2). The selected paraffin-section image used that condition, followed by 2 μg/ml primary antibody overnight at 4°C (caption A02394-2). If staining is weak, adjust heating duration and cooling consistently across control and test sections before evaluating an alternative buffer as a fallback (standard IHC practice). Compare both signal and tissue integrity: stronger staining accompanied by damaged morphology or widespread background does not establish better retrieval (standard IHC practice). Record the retrieval condition with every scored slide so differences in treatment are not mistaken for biological variation (standard IHC practice).
How should I assess whether fixation is masking PPP1R15A?
The selected caption describes a paraffin section but does not state its fixative, so target-specific fixation sensitivity is unknown (caption A02394-2). Do not infer a preferred fixative or fixation duration from the reported tissue staining or membrane association (HPA: tissue IHC; UniProt O75807 topology). For a fixation comparison, process matched specimens with documented conditions, apply the same EDTA pH 8.0 retrieval, and include the same positive control on each run (datasheet A02394-2; standard IHC practice). Compare cellular signal, morphology and background together; altered staining alone cannot distinguish epitope masking from differences in specimen handling or expression (standard IHC practice).
What staining pattern is plausible for PPP1R15A, and when should I question it?
Expect a predominantly granular cytoplasmic pattern in tissue sections, while allowing for variation among cell types (HPA: granular cytoplasmic expression in several tissues). PPP1R15A associates with endoplasmic reticulum and mitochondrial outer membranes through an N-terminal amphipathic region; its annotated topology places residues 1–21 and 40–674 on the cytoplasmic side (UniProt O75807 topology). A vesicular IF location is reported with uncertainty, so it should guide comparison rather than define a required IHC pattern (HPA: vesicles, uncertain). Review strong nuclear-only or uniform extracellular DAB deposits against morphology, a no-primary control and a positive control before calling them target staining (standard IHC practice).
Could isoforms or epitope accessibility explain discordant PPP1R15A staining?
Two isoforms are annotated, but the supplied evidence does not map this antibody’s epitope to either one (UniProt O75807 isoforms; caption A02394-2). Check the antibody’s documented immunogen, if available, before interpreting absent staining as absence of both isoforms (standard IHC practice). PPP1R15A has annotated phosphorylation sites at Ser143 and Tyr262, Tyr391, Tyr434 and Tyr512; their presence does not establish that any modification changes this antibody’s binding (UniProt O75807 modified residues). When samples disagree, retain the same EDTA pH 8.0 retrieval and matched controls, then distinguish a possible epitope effect from variable expression or processing with independent evidence (datasheet A02394-2; standard IHC practice).
How can I check PPP1R15A by IF alongside the chromogenic IHC result?
Treat IF/ICC as a separate validation experiment; the selected antibody evidence describes paraffin-section chromogenic detection, while HPA reports IF images in A-431 and U-251MG cells without establishing this antibody’s IF conditions (caption A02394-2; HPA: subcellular). Multiplex PPP1R15A with a validated marker of the expected cell type, and inspect each channel separately before judging overlap (standard IF practice). Choose fluorophores after measuring tissue autofluorescence, favoring a cleaner emission channel for the weaker signal (standard IF practice). Because the annotated membrane-associated regions face the cytoplasm, assess permeabilisation for access to the antibody’s documented epitope; its location is not supplied here (UniProt O75807 topology; standard IF practice).
What should I adjust when PPP1R15A DAB staining is diffuse?
First compare a no-primary section with the test section to identify signal from detection reagents or endogenous peroxidase (standard IHC practice). The selected image used 10% goat serum blocking, 2 μg/ml primary antibody overnight at 4°C, and a peroxidase-conjugated secondary for 30 minutes at 37°C (caption A02394-2). Use an appropriate peroxidase block and monitor DAB development as general chromogenic workflow steps, then reassess washing and primary concentration if the no-primary section is clean (standard IHC practice). Preserve granular cytoplasmic signal when optimizing, and compare any change on adjacent sections processed in the same run (HPA: tissue profile; standard IHC practice).
How should I score PPP1R15A staining across heterogeneous sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and cytoplasmic scoring area before looking at group labels, since HPA reports granular cytoplasmic staining with different levels across tissues and cell types (HPA: tissue IHC). For cell-based scoring, report the percentage of positive cells and an H-score using intensity categories 0–3, calculated as the sum of each percentage multiplied by its intensity (standard IHC practice). If counting positive cells per mm², normalize to evaluable tissue area or the relevant cell population, excluding acellular and necrotic regions (standard IHC practice). Apply one threshold, imaging setup and control-based batch correction across samples, and report cell identity alongside the score (standard IHC practice).
How can I separate genuine PPP1R15A signal from tissue artefact?
A convincing result places granular cytoplasmic staining in intact cells and is reproducible in an appropriate positive control (HPA: tissue profile; standard IHC practice). HPA reports high staining in duodenal and prostate glandular cells, while cervical squamous epithelial cells and cardiomyocytes were not detected; use these as tissue-context comparisons, not absolute specificity tests (HPA: tissue IHC). Scrutinize nuclear-only signal, staining confined to section edges or necrosis, and deposits persisting without primary antibody for localisation or detection artefacts (UniProt O75807 topology; standard IHC practice). Endogenous peroxidase can mimic DAB positivity, so compare a no-primary control and peroxidase-blocked sections before attributing deposits to PPP1R15A (standard IHC practice).
Boster reagents
Best PPP1R15A / Protein phosphatase 1 regulatory subunit 15A IHC Antibodies
The catalog includes rabbit anti-PPP1R15A antibodies for IHC and IF/ICC in human samples, with rat reactivity listed for both and mouse reactivity for A02394-5 (catalog: applications and reactivity). A02394-2 has a human paraffin-section IHC figure (caption: A02394-2).
Real IHC data
Anti-GADD34/PPP1R15A Antibody ®
Cat # A02394-2
A02394-2 has a human paraffin-section IHC image and lists IF/ICC among its applications (caption and catalog: A02394-2). A02394-5 lists IHC and IF/ICC with human, mouse and rat reactivity; no IHC or IF figure is supplied for it (catalog: A02394-5).
Which to pick: Choose A02394-2 for human paraffin-section IHC because its own caption documents EDTA retrieval at pH 8.0 and staining at 2 μg/ml; the fixative is unreported (caption: A02394-2). For IF/ICC, both SKUs list the application, with 5 μg/ml for A02394-2 and 1:50 for A02394-5; neither has a supplied IF image (catalog: A02394-2, A02394-5). For work that includes mouse samples, choose the rabbit polyclonal A02394-5, which lists human, mouse and rat reactivity; its IHC processing is undocumented by an image caption (catalog: A02394-5).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry O75807 (PR15A_HUMAN, Protein phosphatase 1 regulatory subunit 15A).
- Human Protein Atlas. PPP1R15A tissue IHC expression (reliability: Approved).
- Human Protein Atlas. PPP1R15A subcellular location (ICC-IF): Localized to vesicles..
- Human Protein Atlas. PPP1R15A antibody validation summary (2 antibodies).
- Sensitization of the UPR by loss of PPP1R15A promotes fibrosis and senescence in IPF. Scientific reports 2021 — PMC8566588.
- Protein phosphatase 1 regulatory subunit 15 A promotes translation initiation and induces G2M phase arrest during cuproptosis in cancers. Cell death & disease 2024 — PMC10873343.
- PPP1R15A-expressing monocytic MDSCs promote immunosuppressive liver microenvironment in fibrosis-associated hepatocellular carcinoma. JHEP reports : innovation in hepatology 2024 — PMC11179254.
- Exploration of differential expression and biological significance of amino acid metabolism genes in osteoarthritis. Frontiers in immunology 2025 — PMC12301216.
- PubMed PMID:9153226 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
- PubMed PMID:15489334 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for PPP1R15A (Protein phosphatase 1 regulatory subunit 15A). Expected localisation Granular cytoplasm (HPA tissue IHC); ER/outer mitochondrial membrane expected (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A02394-2). Validated IHC antibody: A02394-2 at 2-5 μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Duodenum (Glandular cells); negative Cervix. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human melanom tissue; fixative not specified (datasheet A02394-2); 2. Fixation: Image fixative and duration unreported (datasheet A02394-2); 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 A02394-2); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A02394-2); 8. Primary antibody: Rabbit anti-PPP1R15A, 2-5 μg/ml (datasheet A02394-2); 9. Primary incubation: Overnight at 4 °C (datasheet A02394-2). Watch for: Fixation: Keep fixation consistent across sections. (standard IHC practice; not target-specific); Caveat: Antibody staining has medium concordance with RNA expression (HPA tissue IHC); Isoform / epitope: 2 isoforms; check epitope coverage across both (UniProt); Regulation: Growth arrest and DNA damage inducible (UniProt). Evidence: UniProt O75807, HPA tissue IHC · Approved, HPA ICC-IF · vesicles., Datasheet A02394-2, PMC8566588. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/PPP1R15A/immunohistochemistry-ihc-guide.