PEG10 / Retrotransposon-derived protein PEG10 · IHC design guide

Design Immunohistochemistry for PEG10

Plan chromogenic PEG10 IHC in paraffin sections using placental cytotrophoblasts as a strong-staining reference (HPA tissue IHC). Start within the catalog antibody's 1:50–1:200 IHC dilution range (datasheet A03240-2) and score cytoplasmic staining by cell type.

Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
Immunohistochemistry protocol sheet for PEG10 (IHC for PEG10): expected localisation Cytoplasm in placental cytotrophoblasts (HPA tissue IHC), antibody A03240-2, validated IHC image, and IHC protocol steps
Printable PEG10 IHC protocol sheet — expected localisation Cytoplasm in placental cytotrophoblasts (HPA tissue IHC), antibody A03240-2, controls and protocol steps. Open the full PEG10 IHC guide →

PEG10 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 Cytoplasm in placental cytotrophoblasts (HPA tissue IHC)
Staining pattern Cytoplasmic staining in placental cytotrophoblasts (HPA tissue IHC)
Antigen retrieval Citrate pH 6.0 HIER, heat-mediated (datasheet A03240-2)
Positive control ⓘ Placenta+3 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 paraffin sections. (standard IHC practice; not target-specific)
Caveat Breast and prostate carcinomas may stain despite negative normal epithelium (UniProt)
Regulation Expressed in breast and prostate carcinomas (UniProt)
Isoform / epitope 5 isoforms; epitope coverage is unknown, with no transmembrane split between extracellular and cytoplasmic epitopes (UniProt)
Section 1

Recommended PEG10 IHC & IF Protocols

Compare the catalog antibody’s IHC-P protocol (datasheet A03240-2) with published PEG10 protocols for placenta, hepatocellular carcinoma, breast tumors, and gallbladder carcinoma (PMC10355026; PMC4614193; PMC10683152; PMC3961444).

Recommended immunohistochemistry (IHC-P) protocol parameters
SampleParaffin-embedded rat testis tissue; fixative not specified (datasheet A03240-2)
FixationImage fixative and duration unreported (datasheet A03240-2); verify before use.
Sectioning4–5 µm sections on charged slides (standard)
DeparaffinisationXylene, graded ethanol series to water (standard)
Antigen retrievalHeat retrieval: Citrate pH 6.0 (datasheet A03240-2); 20 min, 95–100 °C (standard)
Peroxidase block3% H2O2, 10 min, room temperature (standard)
Blocking10% normal serum of the secondary host, 30 min, room temperature (standard)
Primary antibodyRabbit anti-PEG10, 1:50-1:200 (datasheet A03240-2)
Primary incubationOvernight at 4 °C (standard)
DetectionHRP-polymer secondary, DAB chromogen 5–10 min (standard)
CounterstainHematoxylin, blue, dehydrate and mount (standard)
Expected resultPEG10-positive staining in cytotrophoblasts of placenta (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression in placental cytotrophoblasts and adrenal gland. No signal in the no-primary control.
💡Decision noteStart with heat-mediated citrate retrieval at pH 6.0 (datasheet A03240-2); the placental and hepatocellular carcinoma protocols also use citrate at pH 6.0 (PMC10355026; PMC4614193).
Section 2

What Is the Expected PEG10 Staining Pattern?

PEG10 staining should be predominantly cytoplasmic in placental cytotrophoblasts, with cytoplasmic expression also reported in adrenal glandular cells (HPA tissue IHC: Enhanced reliability). High staining is reported in placental cytotrophoblasts and late spermatids; adrenal glandular cells show medium staining (HPA tissue IHC). UniProt also lists cytoplasmic, nuclear and extracellular vesicle membrane localization, with no transmembrane segment (UniProt Q86TG7 topology and subcellular location).

What am I looking at on my slide?
Placental cytotrophoblasts show strong cytoplasmic chromogen, while the overlying syncytiotrophoblast is unstained.This is the clearest cell-level reference pattern: cytotrophoblast staining is High (HPA tissue IHC), and expression is reported in cytotrophoblasts but not overlying syncytiotrophoblast (UniProt Q86TG7 tissue specificity). Score the two layers separately rather than treating the whole placenta as uniformly positive.
Late spermatids stain strongly, or adrenal glandular cells stain at moderate intensity.These are additional reported positive cell populations: High in elongated or late spermatids and Medium in adrenal glandular cells (HPA tissue IHC). The supplied HPA profile specifies cytoplasmic expression for placenta and adrenal gland; it does not specify the compartment within spermatids (HPA tissue IHC).
A section shows predominantly nuclear staining, with little cytoplasmic staining.Reassess the IHC result against the predominantly cytoplasmic tissue pattern (HPA tissue IHC). Nuclear PEG10 cannot be ruled out categorically: UniProt lists nucleus, and HPA ICC-IF reports additional approved nucleoplasmic localization (UniProt Q86TG7 subcellular location; HPA subcellular ICC-IF). Nuclear-only IHC is therefore a discrepancy to investigate, not proof of specificity.
Strong chromogen appears in an HPA-listed negative cell population, or color spreads uniformly across the section.Adipocytes and appendix glandular cells are reported Not detected (HPA tissue IHC). Unexpected cell staining warrants a cross-reactivity or endogenous detection-activity check (general IHC practice). Diffuse color without cell boundaries is background and cannot establish PEG10 localization (general IHC interpretation).
Placental cytotrophoblasts show no discernible signal.A negative result conflicts with the reported High cytotrophoblast staining (HPA tissue IHC). Review the positive control and detection workflow before interpreting other tissues as negative (general IHC practice). The supplied sources do not establish a PEG10-specific fixation effect or an antigen retrieval requirement.
💡Expected PEG10 appearanceCall a section positive when clearly bounded placental cytotrophoblast cytoplasm shows strong staining (HPA tissue IHC: High, cytoplasmic); widespread color outside cells or staining confined to an unexpected population warrants a background or specificity check (general IHC interpretation).
How each factor affects the staining
Cell population and tissuePEG10 staining is cell-specific: cytotrophoblasts and late spermatids are High, while adrenal glandular cells and skin granular-layer cells are Medium (HPA tissue IHC). Adipocytes are Not detected in HPA tissue IHC, although UniProt lists expression in adipose tissue without assigning it to adipocytes (UniProt Q86TG7 tissue specificity). Compare like cell populations when scoring.
Subcellular locationThe tissue IHC profile emphasizes cytoplasmic expression in placental cytotrophoblasts and adrenal gland (HPA tissue IHC). UniProt additionally lists nucleus and extracellular vesicle membrane and describes released virion-like vesicles (UniProt Q86TG7 subcellular location). Those annotations do not, by themselves, establish a visible membrane staining pattern in a paraffin section.
Isoforms and antibody epitopeUniProt lists five PEG10 isoforms (UniProt Q86TG7 isoforms). The supplied evidence does not identify the epitope recognized by a particular IHC antibody or establish equal recognition of all isoforms. Interpret staining as antibody-dependent PEG10 detection; do not assign an isoform from chromogen distribution alone.
Antibody validationThree listed antibodies have Enhanced IHC status (HPA antibodies: HPA021324, HPA029915, HPA051038). The tissue profile also has Enhanced reliability, described as high consistency between staining and RNA expression (HPA tissue IHC). These support the reported pattern, while unexpected staining still needs controls on the actual section (general IHC practice).
Why is my staining missing, weak or wrong?
SituationLikely causeNext action
Known-positive placenta is blank.The observed result differs from High cytotrophoblast staining (HPA tissue IHC); the failed step cannot be identified from the image alone.Check tissue preservation, retrieval, primary-antibody incubation and chromogenic detection with appropriate controls (general IHC practice). Treat retrieval as a workflow variable; no PEG10-specific retrieval or fixation sensitivity is supplied.
Color covers both tissue and empty slide areas.A distribution without cell boundaries is consistent with nonspecific deposition or detection background (general IHC practice), rather than the cytoplasmic placental profile (HPA tissue IHC).Inspect no-primary and detection controls, blocking, washes and chromogen development (general IHC practice). Re-score only bounded cellular staining after background is controlled.
Unexpected cells stain as strongly as cytotrophoblasts.This may reflect cross-reactivity or endogenous detection activity (general IHC practice). HPA reports some populations, including adipocytes, as Not detected (HPA tissue IHC).Identify the exact stained cell population, compare it with the HPA tissue entry, and review an appropriate negative control (general IHC practice). Do not label an entire tissue negative when its cell populations differ.
Staining is mainly nuclear in placenta.It departs from the cytoplasmic placental IHC profile (HPA tissue IHC), although nuclear localization is listed by UniProt and nucleoplasmic localization is approved in HPA ICC-IF (UniProt Q86TG7; HPA subcellular ICC-IF).Check whether cytoplasmic signal is also present, review controls, and compare another IHC-validated antibody if available (HPA antibodies: three Enhanced IHC entries; general IHC practice). Report the compartment observed rather than forcing a cytoplasmic score.
Adipocytes are negative despite a general expression listing for adipose tissue.The annotations have different resolution: HPA reports adipocytes Not detected, while UniProt lists expression in adipose tissue without specifying adipocytes (HPA tissue IHC; UniProt Q86TG7 tissue specificity).Score the identified adipocytes against the cell-level HPA result. Keep the tissue-level UniProt listing as context rather than treating it as a predicted positive adipocyte control.
Can an IF/ICC image settle an ambiguous paraffin IHC result?The assays provide related but different observations: HPA ICC-IF approves mainly cytosolic and additional nucleoplasmic localization, whereas its tissue IHC profile describes cytoplasmic placental and adrenal expression (HPA subcellular ICC-IF; HPA tissue IHC).Use the IF/ICC localization as context, then resolve the paraffin-section result with its own cell-level pattern and IHC controls (general IHC practice). Follow the separate IF/ICC guide for that application.

Sample controls for PEG10 IHC & IF

🧪Run placenta first: cytotrophoblasts should stain strongly (HPA: High in cytotrophoblasts). Use appendix glandular cells as a negative tissue (HPA: Not detected), and expect the adjacent syncytiotrophoblast layer on the placenta slide to remain unstained (UniProt Q86TG7: PEG10 is expressed in cytotrophoblasts but not syncytiotrophoblasts).
Positive control tissue: Placenta (Cytotrophoblasts, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show PEG10 in Hep-G2, Rh30, U2OS, with annotated localisation: Cytosol (approved) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control, a matched rabbit polyclonal IgG isotype control (selected caption: rabbit pAb), and PEG10 knockout tissue if available as a biological negative (standard IHC practice). For placental chromogenic IHC, block endogenous peroxidase and assess blood-rich areas for background (standard IHC practice).
⚠️Feasibility: No target-specific fixation window or fixation effect is reported, and the selected A03240-2 paraffin-section caption does not state the fixative (selected caption: fixative unreported). That caption uses high-pressure retrieval in 10 mM citrate buffer at pH 6.0 before IHC, but does not establish that retrieval is required under other conditions (selected caption). Paraffin IHC has a documented starting condition; frozen-section ease is unreported, while IF/ICC has HPA images showing mainly cytosolic and additional nucleoplasmic localization (HPA: subcellular).

HPA tissue IHC evidence for PEG10

Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — High 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

TissueCell typeLevelEvidenceSource
Placenta Cytotrophoblasts High Protein (IHC) HPA →
Testis Elongated or late spermatids High Protein (IHC) HPA →
Adrenal gland Glandular cells Medium Protein (IHC) HPA →
Skin Cells in granular layer Medium Protein (IHC) HPA →

Undetected expression · recommended negative controls

TissueCell typeLevelEvidenceSource
Adipose tissue Adipocytes Not detected Protein (IHC) HPA →
Appendix Glandular cells Not detected Protein (IHC) HPA →
Bone marrow Hematopoietic cells Not detected Protein (IHC) HPA →
Breast Adipocytes Not detected Protein (IHC) HPA →
Bronchus Respiratory epithelial cells Not detected Protein (IHC) HPA →
Section 3

Advanced PEG10 IHC Tips

Troubleshoot PEG10 staining by checking retrieval, cell type and subcellular pattern before comparing signal across sections (datasheet A03240-2; HPA tissue IHC; HPA subcellular).

How should I retrieve PEG10 in paraffin sections when staining is weak?
Use heat-mediated retrieval in 10 mM citrate at pH 6.0 for paraffin sections (datasheet A03240-2). The selected rat testis image used high-pressure retrieval in that buffer before staining with the catalog antibody at 1:100 (caption A03240-2). If signal is weak, first check that sections reached retrieval temperature consistently and compare a shorter and longer heating interval, such as 10 and 20 minutes, on adjacent sections (standard IHC practice). Keep cooling, blocking and detection conditions matched so retrieval is the tested variable (standard IHC practice). Assess whether cytoplasmic staining gains contrast without a parallel increase in diffuse background (HPA tissue IHC; standard IHC practice).
Could fixation explain weak PEG10 staining in my paraffin sections?
Target-specific sensitivity of PEG10 staining to fixation is unknown from the supplied evidence; the selected paraffin-section caption does not state its fixative (caption A03240-2). Record the fixative, fixation duration and tissue thickness for each specimen before comparing staining intensity (standard IHC practice). Process adjacent specimens consistently where possible, then assess staining after the specified citrate retrieval rather than attributing a weak result to fixation alone (datasheet A03240-2; standard IHC practice). Include a known positive tissue section in the same staining run to distinguish a specimen-level problem from a run-level problem (HPA tissue IHC; standard IHC practice). Neither the HPA expression pattern nor PEG10 topology establishes a fixation effect (HPA tissue IHC; UniProt Q86TG7).
Which staining compartments should I accept as plausible for PEG10?
Prioritise cytoplasmic staining in the expected cells: HPA reports cytoplasmic expression in placental cytotrophoblasts and adrenal gland (HPA tissue IHC). Cytosol is the approved main location, with nucleoplasm an additional approved location in cell imaging (HPA subcellular). UniProt also lists nucleus and extracellular vesicle membrane, and PEG10 has no annotated transmembrane segment (UniProt Q86TG7). Score cytoplasmic and nuclear signal separately, using a counterstain to identify cell boundaries and nuclei (HPA subcellular; standard IHC practice). Treat isolated membrane-like outlines or extracellular deposits cautiously unless they follow a reproducible cell-associated pattern and remain absent in detection controls (UniProt Q86TG7; standard IHC practice).
How could PEG10 isoforms or epitope accessibility change the staining pattern?
PEG10 has five annotated isoforms, so check the antibody's stated immunogen or epitope against the sequence represented by each isoform before interpreting negative staining (UniProt Q86TG7; standard IHC practice). The supplied caption documents staining conditions but does not locate the catalog antibody's epitope (caption A03240-2). PEG10 also has annotated methylarginines and phosphoserines; these annotations alone do not show that either modification changes antibody binding (UniProt Q86TG7). If two antibodies produce different patterns, compare their disclosed epitopes and stain adjacent sections under matched retrieval and detection conditions (standard IHC practice). Report the antibody identity and retrieval conditions with any isoform-specific interpretation (standard IHC practice).
How should I investigate PEG10 localisation by multiplex immunofluorescence?
Use IF as a separate validation experiment; the selected antibody evidence here describes paraffin-section chromogenic IHC, with no IF protocol supplied (caption A03240-2). Pair PEG10 with a validated marker of the expected cell type, such as a cytotrophoblast marker in placenta, and include a nuclear counterstain (HPA tissue IHC; standard IF practice). Check unstained tissue for autofluorescence, then choose spectrally separated fluorophores and acquire single-label controls before judging colocalisation (standard IF practice). Because PEG10 has no annotated transmembrane segment and is mainly cytosolic, optimise mild permeabilisation for intracellular access; do not assume an extracellular-facing epitope (UniProt Q86TG7; HPA subcellular; standard IF practice).
How can I reduce diffuse brown background without losing PEG10 signal?
Compare a no-primary control with the PEG10-stained section to identify detection-derived colour before changing antibody concentration (standard IHC practice). Block endogenous peroxidase before chromogenic detection and use a matched secondary-reagent control where the detection system permits (standard IHC practice). If background persists, titrate around the selected image's 1:100 primary-antibody dilution while keeping citrate retrieval at pH 6.0 fixed (caption A03240-2; standard IHC practice). Wash consistently, inspect tissue edges and necrotic regions, and avoid scoring precipitate or broadly distributed brown haze as cellular signal (standard IHC practice). Preserve detectable cytoplasmic contrast in an expected positive cell population when selecting the final conditions (HPA tissue IHC; standard IHC practice).
What is a defensible way to quantify PEG10-positive cells in tissue? ⚠ ANSWER MARKED FOR VERIFICATION
Define the scored cell population and region before measuring PEG10, because HPA reports high staining in placental cytotrophoblasts and late or elongated spermatids but no detection in several other sampled cell populations (HPA tissue IHC; standard IHC practice). For chromogenic sections, report the percentage of positive cells and an H-score from intensity categories 0–3, or positive-cell density per mm² when counts are spatially important (standard IHC practice). Normalise counts to eligible cells or measured viable tissue area, respectively (standard IHC practice). Score cytoplasmic and nuclear staining separately and hold exposure, threshold and exclusion rules constant across groups (HPA subcellular; standard IHC practice).
When is an apparent PEG10-positive region more likely to be artefact?
A convincing result places signal in identifiable cells and a plausible compartment, particularly cytoplasm in placental cytotrophoblasts (HPA tissue IHC; HPA subcellular). HPA also reports high staining in elongated or late spermatids, so interpret testis staining by cell type rather than by a whole-section average (HPA tissue IHC; standard IHC practice). Be cautious with colour confined to cut edges, necrotic areas or vessels, and compare those regions with no-primary and peroxidase-block controls (standard IHC practice). Nuclear staining is possible, but a diffuse nuclear-only pattern across unrelated cells warrants checking specificity and counterstain alignment (HPA subcellular; standard IHC practice). Reproducibility across adjacent sections and expected cells strengthens interpretation (HPA tissue IHC; standard IHC practice).
Boster reagents

Best PEG10 / Retrotransposon-derived protein PEG10 IHC Antibodies

Two anti-PEG10 antibodies have paraffin-section IHC images from human tissue and rat testis (catalog IHC captions); one also has IF data from methanol-fixed HepG2 cells (A03240 IF caption).

Real IHC data Immunohistochemistry of paraffin-embedded rat testis using PEG10 Rabbit pAb at dilution of 1:100 .Perform high pressure antigen retrieval with 10 mM citrate buffer pH 6.0 before commencing with IHC staining protocol.
Anti-PEG10 Antibody
Cat # A03240-2
Real IHC data Immunohistochemistry (IHC) analysis of paraffin-embedded human Placenta tissues with AEC staining using PEG10 Monoclonal antibody.
Anti-PEG10 Monoclonal Antibody
Cat # A03240

A03240-2 has IHC images of paraffin-embedded rat testis, human breast cancer, and human placenta (A03240-2 IHC captions). A03240 has an IHC image of paraffin-embedded human placenta and an IF image of methanol-fixed HepG2 cells (A03240 IHC and IF captions).

Which to pick: For tissue IHC, choose the rabbit antibody A03240-2 when its rat testis or human tissue examples fit your sample; its captions specify citrate retrieval at pH 6.0 and 1:100 antibody dilution (A03240-2 IHC captions). For IF in cultured cells, choose the mouse monoclonal A03240, which lists IF and shows cytoplasmic staining in methanol-fixed HepG2 cells (A03240 applications and IF caption). For mouse or rat tissue IHC, A03240-2 lists those species, while A03240 lists human only; both IHC captions describe paraffin-embedded sections, but neither reports the tissue fixative (catalog reactivity and IHC captions).

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

References

  1. UniProt Consortium. UniProt entry Q86TG7 (PEG10_HUMAN, Retrotransposon-derived protein PEG10).
  2. Human Protein Atlas. PEG10 tissue IHC expression (reliability: Enhanced).
  3. Human Protein Atlas. PEG10 subcellular location (ICC-IF): Mainly localized to the cytosol. In addition localized to the nucleoplasm..
  4. Human Protein Atlas. PEG10 antibody validation summary (3 antibodies).
  5. Paternal Expressed Gene 10 (PEG10) is decreased in early-onset preeclampsia. Reproductive biology and endocrinology : RB&E 2023 — PMC10355026.
  6. Expression of PEG10 Is Associated with Poor Survival and Tumor Recurrence in Hepatocellular Carcinoma. Cancer research and treatment 2015 — PMC4614193.
  7. Targeting PEG10 as a novel therapeutic approach to overcome CDK4/6 inhibitor resistance in breast cancer. Journal of experimental & clinical cancer research : CR 2023 — PMC10683152.
  8. TSG101 and PEG10 are prognostic markers in squamous cell/adenosquamous carcinomas and adenocarcinoma of the gallbladder. Oncology letters 2014 — PMC3961444.
  9. PubMed PMID:11318613 — UniProt-cited evidence.
  10. PubMed PMID:10231032 — UniProt-cited evidence.
  11. PubMed PMID:14702039 — UniProt-cited evidence.