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PCBP2 / Poly(rC)-binding protein 2 · IHC design guide
Design Immunohistochemistry for PCBP2
Plan chromogenic PCBP2 IHC in paraffin sections with the IHC-validated antibody at 2–5 μg/mL (datasheet: A02425-2). Use kidney tubule cells as a high-staining reference and assess signal with HPA’s off-target warning in mind (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
PCBP2 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 in tissue (HPA tissue IHC); nuclear possible (UniProt) | |
| Staining pattern | Cytoplasmic staining; high in kidney tubule cells (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A02425-2) | |
| Positive control | Bronchus+4 more · see all | |
| Negative control | Adipose tissue |
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 | Presumed off-target staining complicates attribution (HPA tissue IHC) | |
| Regulation | No specific expression inducer reported (UniProt) | |
| Isoform / epitope | 8 isoforms; epitope coverage is unknown (UniProt) |
Section 1
Recommended PCBP2 IHC & IF Protocols
The catalog antibody uses heat-mediated EDTA pH 8.0 retrieval (datasheet: A02425-2). The published chromogenic IHC protocols below report PCBP2 staining in melanoma, placental explants, and mouse tissues (PMC10474410; PMC8172583; PMC12914862).
| Sample | Paraffin-embedded mouse brain tissue; fixative not specified (datasheet A02425-2) |
| Fixation | Image fixative and duration unreported (datasheet A02425-2); 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 A02425-2); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A02425-2) |
| Primary antibody | Rabbit anti-PCBP2, 2-5μg/ml (datasheet A02425-2) |
| Primary incubation | Overnight at 4 °C (datasheet A02425-2) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet A02425-2) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | PCBP2-positive staining in respiratory epithelial cells of bronchus (HPA tissue IHC: High). HPA tissue profile: General cytoplasmic expression. No signal in the no-primary control. |
💡Decision noteStart with EDTA pH 8.0 for the catalog antibody (datasheet: A02425-2); evaluate citrate retrieval when adapting the published protocols (PMC10474410; PMC8172583).
Section 2
What Is the Expected PCBP2 Staining Pattern?
PCBP2 is nuclear and cytoplasmic and may shuttle between them (UniProt Q15366: subcellular location). In paraffin IHC, expect predominantly cytoplasmic staining in responsive cells, including kidney tubular cells, hepatocytes, respiratory epithelial cells and Purkinje cells (HPA: tissue IHC). HPA rates the tissue pattern Approved, while reporting medium agreement with RNA and suspected off-target binding; its staining is therefore a reference pattern, not proof of antibody specificity (HPA: tissue IHC reliability).
| Cytoplasmic staining in kidney tubular cells or hepatocytes, with intact tissue detail and restrained background. | This agrees with the reported general cytoplasmic IHC pattern and High staining in both cell populations (HPA: tissue IHC). Judge the distribution against neighboring structures and a negative reagent control; color alone cannot establish target identity (general IHC practice). |
| Predominantly cell-surface, luminal or extracellular staining, with little intracellular signal. | Those compartments do not match PCBP2's nuclear and cytoplasmic location or the reported cytoplasmic IHC profile (UniProt Q15366: subcellular location; HPA: tissue IHC). Suspect nonspecific deposition or detection artefact first, then reassess with controls (general IHC practice). Nuclear signal alone needs more caution because nuclear PCBP2 is documented (UniProt Q15366: subcellular location). |
| Strong adipocyte staining when expected positive cells on the same run stain poorly. | Adipocytes are Not detected in the supplied HPA tissue IHC profile, whereas kidney tubular cells and hepatocytes are High (HPA: tissue IHC). This mismatch raises concern for cross-reactivity or endogenous detection activity; it does not prove either mechanism, especially given HPA's stated off-target caution (HPA: tissue IHC reliability). |
| Uniform brown haze across cells and extracellular space, obscuring cell boundaries. | A field-wide haze is difficult to reconcile with interpretable intracellular staining (HPA: tissue IHC profile). Check the negative reagent control, wash quality and detection background before assigning any cell as positive (general IHC practice). The HPA profile cannot identify which workflow step caused the haze. |
| No convincing staining in kidney tubular cells or hepatocytes despite preserved tissue detail. | Both populations are reported High by HPA, so their absence makes this run uninformative until a positive control and detection steps are checked (HPA: tissue IHC). A blank section alone cannot distinguish low antigen recovery, inadequate antibody activity or a detection failure (general IHC practice). |
💡Expected PCBP2 appearanceCall a result positive when intracellular, mainly cytoplasmic stain is convincing in kidney tubular cells or hepatocytes at HPA's High level; isolated extracellular or cell-surface color is suspect (HPA: tissue IHC; UniProt Q15366: subcellular location).
| Compartment and assay | HPA describes general cytoplasmic expression in tissue IHC; UniProt lists nucleus and cytoplasm, with possible shuttling (HPA: tissue IHC; UniProt Q15366: subcellular location). Score paraffin IHC against its cytoplasmic reference while recording credible nuclear staining separately. |
| Tissue and cell context | HPA reports High staining in respiratory epithelium, Purkinje cells, kidney tubules, hepatocytes and other listed populations, but Not detected in adipocytes (HPA: tissue IHC). Use a reported High population as a positive comparator; avoid treating every unstained cell as assay failure. |
| Antibody evidence | Two listed antibodies have Approved IHC status, but HPA reports medium agreement with RNA, possible recognition of more than one gene and disregarded presumed off-target binding (HPA: antibody validation; HPA: tissue IHC reliability). Match the actual antibody and controls before interpreting an unexpected pattern. |
| Isoforms and epitope uncertainty | UniProt lists 8 PCBP2 isoforms and three KH domains (UniProt Q15366: isoforms and domains). The supplied evidence gives no antibody epitope or isoform coverage, so differences among sections cannot be assigned to a particular isoform from staining alone. |
| IF/ICC Q: Where should signal appear? | A: HPA supports nucleoplasm and cytosol in ICC-IF and lists images from A-431, U-251MG and U2OS (HPA: subcellular ICC-IF). This answers localization only; IF/ICC preparation and detection belong to its separate guide. |
| Situation | Likely cause | Next action |
|---|---|---|
| A reported High control tissue is blank. | A failed run is possible; kidney tubular cells and hepatocytes are reported High (HPA: tissue IHC). | Check the positive control, antibody application and detection reagents, then review retrieval conditions using the catalog antibody's IHC-P instructions (general IHC practice). Do not infer PCBP2-specific fixation sensitivity; none is supplied. |
| All sections show weak, hard-to-score intracellular color. | Low assay signal is possible; HPA's High reference populations should be easier to assess (HPA: tissue IHC). | Confirm that the catalog antibody is used within its documented IHC-P conditions and that controls develop as expected; compare the same cell population across sections (general IHC practice). No dilution is supplied here. |
| Signal appears mainly nuclear. | Nuclear PCBP2 is biologically plausible, although HPA summarizes tissue IHC as generally cytoplasmic (UniProt Q15366: subcellular location; HPA: tissue IHC). | Record nuclear and cytoplasmic scores separately, inspect a reported High control and compare negative reagent controls (general IHC practice). Do not discard nuclear signal solely because the tissue summary emphasizes cytoplasm. |
| Cell surfaces or extracellular material stain strongly. | This distribution conflicts with the documented intracellular locations and HPA's general cytoplasmic IHC pattern (UniProt Q15366: subcellular location; HPA: tissue IHC). | Inspect a negative reagent control and tissue morphology, then review wash and chromogen steps for deposition (general IHC practice). Avoid calling this PCBP2 without convincing intracellular staining. |
| Adipocytes stain as strongly as reported High populations. | Adipocytes are Not detected in HPA tissue IHC; its reliability note also flags presumed off-target binding (HPA: tissue IHC). | Compare a reported High cell population and negative reagent control in the same run; check for endogenous detection activity with appropriate controls (general IHC practice). Treat the adipocyte result as unresolved until corroborated. |
| Diffuse brown background obscures cellular detail. | The pattern prevents comparison with HPA's cell-specific observations; its source does not assign a cause to background (HPA: tissue IHC). | Review blocking, washing, detection incubation and negative reagent controls, then repeat scoring only where cell boundaries are clear (general IHC practice). |
Experiment evidence
IHC & IF images showing PCBP2 staining
A02425-2 · IHCIHC analysis of PCBP2/hnRNP E2 using anti-PCBP2/hnRNP E2 antibody (A02425-2). PCBP2/hnRNP E2 was detected in paraffin-embedded section of mo
A02425-2 · IHCIHC analysis of PCBP2/hnRNP E2 using anti-PCBP2/hnRNP E2 antibody (A02425-2). PCBP2/hnRNP E2 was detected in paraffin-embedded section of ra
A02425-3 · IFIF analysis of hnRNP E2/PCBP2 using anti-hnRNP E2/PCBP2 antibody (A02425-3) and anti-Tubulin Alpha antibody (M03989-3). hnRNP E2/PCBP2 was d
M02425 · IFIF analysis of PCBP2/hnRNP E2 using anti-PCBP2/hnRNP E2 antibody (M02425). PCBP2/hnRNP E2 was detected in an immunocytochemical section of C
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000197111-PCBP2/tissue/cerebral+cortex#imid_9778780
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000197111-PCBP2/tissue/colon#imid_9778690
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000197111-PCBP2/tissue/liver#imid_9778699
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000197111-PCBP2/tissue/kidney#imid_9778700
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA038356; green = PCBP2, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA038356; green = PCBP2, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for PCBP2 IHC & IF
🧪Run bronchus first: respiratory epithelial cells should stain strongly (HPA: High in bronchus respiratory epithelial cells). Run adipose tissue as the negative tissue because adipocytes are listed as not detected (HPA: Not detected in adipocytes); on the bronchus slide, any cells used as internal negatives should show counterstain without DAB, but their PCBP2 status must be verified rather than assumed (standard IHC practice).
Positive control tissue: Bronchus (Respiratory epithelial cells, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show PCBP2 in A-431, U-251MG, U2OS, with annotated localisation: Nucleoplasm (supported), Cytosol (supported) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control and a concentration-matched rabbit IgG isotype control (caption: rabbit primary antibody; standard IHC practice); use PCBP2 knockout tissue, if available, as a biological specificity control (standard IHC practice). For bronchus, quench endogenous peroxidase and check for endogenous biotin background with the biotin-based SABC/DAB detection system (caption: biotinylated secondary, SABC and DAB; standard IHC practice).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected A02425-2 paraffin-section caption does not state the fixative (caption: fixative unreported). Heat retrieval in EDTA at pH 8.0 is reported for the selected IHC example; whether retrieval is required, or whether frozen sections or IF are easier, is unreported (caption: EDTA retrieval; supplied evidence: no comparison). No bronchus-specific artefact is documented in the supplied evidence; inspect background in the planned SABC/DAB assay (caption: SABC/DAB; standard IHC practice).
HPA tissue IHC evidence for PCBP2
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Approved — Medium consistency between antibody staining and RNA expression data. Caution, targets protein from more than one gene. Presumed off target binding observed and disregarded.). 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 |
|---|---|---|---|---|
| Bronchus | Respiratory epithelial cells | High | Protein (IHC) | HPA → |
| Cerebellum | Purkinje cells | High | Protein (IHC) | HPA → |
| Kidney | Cells in tubules | High | Protein (IHC) | HPA → |
| Liver | Hepatocytes | High | Protein (IHC) | HPA → |
| Nasopharynx | Respiratory epithelial cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced PCBP2 IHC Tips
Troubleshoot PCBP2 staining in paraffin sections by checking retrieval, cell and compartment patterns, controls, and scoring before interpreting chromogenic signal.
Which retrieval condition should I start with for PCBP2 staining in paraffin sections?
Use heat-mediated antigen retrieval in EDTA at pH 8.0 for paraffin sections before PCBP2 IHC (datasheet A02425-2). Keep heating and cooling conditions consistent across slides, then compare staining with a control section processed in the same run (standard IHC practice). The selected tissue image used 2 µg/mL primary antibody overnight at 4°C, so match that condition while assessing retrieval (datasheet A02425-2). If staining remains weak, vary retrieval duration on adjacent sections before changing antibody concentration (standard IHC practice). Watch for tissue detachment or damaged morphology as signs that the retrieval condition is too harsh (standard IHC practice).
Could fixation explain weak or uneven PCBP2 IHC?
Target-specific fixation sensitivity is unknown: the selected paraffin-section caption does not state a fixative (datasheet A02425-2). Record the fixative, fixation duration, section thickness, and time in storage for each specimen before comparing staining (standard IHC practice). If using 10% neutral buffered formalin, keep processing conditions matched across cases; this is a general tissue-processing practice, not a PCBP2-validated fixation condition (standard IHC practice). Compare adjacent sections with the same EDTA pH 8.0 retrieval and primary-antibody conditions to isolate processing differences (datasheet A02425-2; standard IHC practice). Do not infer fixation effects from the reported tissue distribution or PCBP2 modifications (HPA: tissue IHC; UniProt Q15366).
Should PCBP2 staining be nuclear or cytoplasmic?
Assess both nuclear and cytoplasmic signal: PCBP2 is reported in the nucleus and cytoplasm and may shuttle between them (UniProt Q15366). Supported subcellular locations are nucleoplasm and cytosol, while tissue IHC shows a general cytoplasmic pattern (HPA: subcellular; HPA: tissue IHC). Score the compartments separately in intact cells rather than calling one compartment universally abnormal (standard IHC practice; UniProt Q15366). Compare the pattern within recognizable cells, including Purkinje cells or kidney tubular cells, where high staining is reported (HPA: High in Purkinje cells; HPA: High in kidney tubules). Diffuse staining over tissue edges or spaces between cells needs control-based review before assignment to either compartment (standard IHC practice).
How can isoforms and epitope placement affect PCBP2 IHC interpretation?
PCBP2 has 8 listed isoforms, so check the antibody immunogen against the sequences of the isoforms relevant to your question (UniProt Q15366). Its three KH domains span residues 13–75, 97–162, and 287–351; epitope placement matters when assessing shared or absent sequence (UniProt Q15366). Phosphoserines are reported at residues 173, 189, 272, 364, and 365, but this payload provides no evidence that they alter this antibody’s IHC binding (UniProt Q15366). Use sequence mapping and an independent antibody or orthogonal assay before assigning a staining difference to a particular isoform (standard IHC validation practice). Document the tested epitope and control results alongside any isoform-level claim (standard IHC validation practice).
How should I check PCBP2 localisation with multiplex IF?
Treat IF as a separate validation: the supplied A02425-2 example demonstrates chromogenic staining of paraffin sections, not IF performance (datasheet A02425-2). Pair PCBP2 with a validated marker for the expected cell type, such as a Purkinje-cell marker when examining cerebellum (HPA: High in Purkinje cells; standard IF practice). Choose spectrally separated fluorophores and consider a far-red channel if the tissue has strong shorter-wavelength autofluorescence (standard IF practice). Because PCBP2 is intracellular and has no transmembrane segment, use controlled permeabilisation to access nuclear and cytosolic epitopes, then check morphology and compartment patterns (UniProt Q15366; standard IF practice). Include single-stain and no-primary controls to assess bleed-through and background (standard IF practice).
What should I check when PCBP2 chromogenic staining is diffuse?
Start by separating tissue signal from detection-system background with a no-primary control and matched counterstain (standard IHC practice). The selected protocol blocked sections with 10% goat serum and used 2 µg/mL primary antibody overnight at 4°C (datasheet A02425-2). It then used a biotinylated secondary for 30 minutes at 37°C, followed by a streptavidin–biotin complex and DAB (datasheet A02425-2). Check secondary-only staining and endogenous biotin when troubleshooting this detection scheme; apply a peroxidase block as a general chromogenic IHC step (standard IHC practice). If background persists, compare primary-antibody titrations while keeping retrieval, wash conditions, and DAB development time fixed (standard IHC practice).
How should I quantify PCBP2 staining across tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and compartment before scoring, because PCBP2 can appear in both nucleus and cytoplasm (UniProt Q15366). For chromogenic IHC, report percent positive cells and an H-score calculated as the sum of each 0–3 intensity grade multiplied by its percent of cells, giving 0–300 (standard IHC scoring practice). Alternatively, report positive-cell density per mm² of viable tissue when cell counts per area answer the study question (standard IHC scoring practice). Normalize comparisons to the same cell type, viable area, staining batch, and compartment (standard IHC practice). Record thresholds and exclude folds, edges, and necrotic regions before analysis (standard IHC practice).
How can I distinguish genuine PCBP2 staining from artefact?
Look for cell-associated nucleoplasmic or cytosolic staining in intact cells; those compartments are supported for PCBP2 (HPA: subcellular). High staining in respiratory epithelial cells, Purkinje cells, kidney tubular cells, or hepatocytes is consistent with reported tissue patterns (HPA: tissue IHC). Treat isolated staining at section edges, over necrosis, or outside cells as suspect, and compare it with a no-primary control (standard IHC practice). Review endogenous peroxidase and biotin controls when interpreting DAB signal from the selected streptavidin–biotin workflow (datasheet A02425-2; standard IHC practice). HPA reports presumed off-target binding and medium staining–RNA consistency, so confirm consequential findings with an independent antibody or orthogonal assay (HPA: reliability description).
Boster reagents
Best PCBP2 / Poly(rC)-binding protein 2 IHC Antibodies
Anti-PCBP2 antibodies have IHC images from paraffin sections of mouse and rat brain and human ovarian and pancreatic cancer tissue, plus IF images from human PC-3 and Caco-2 cells (catalog image captions).
Real IHC data
Anti-PCBP2/hnRNP E2 Antibody ®
Cat # A02425-2
Real IF data
Anti-hnRNP E2/PCBP2 Antibody ®
Cat # A02425-3
Real IF data
Anti-PCBP2/hnRNP E2 Antibody ® (monoclonal, 4B9C7)
Cat # M02425
A02425-2 is listed for IHC and has paraffin-section images from mouse and rat brain and human ovarian and pancreatic cancer tissue (catalog: applications; A02425-2 image captions). A02425-3 and M02425 are listed for IF/ICC, with images from PC-3 and Caco-2 cells, respectively (catalog: applications; A02425-3 and M02425 image captions).
Which to pick: Choose A02425-2 for paraffin-section IHC: its images document EDTA retrieval at pH 8.0, 2 μg/ml primary antibody and DAB detection; the fixative is unreported (A02425-2 image captions). For IF/ICC, choose rabbit A02425-3 or mouse monoclonal M02425 according to the host species needed for your staining panel; each has its own cell image (catalog: host and clone; A02425-3 and M02425 image captions). All three list human, mouse and rat reactivity, but the IF/ICC images show human cells only, while A02425-2 has tissue images from all three species (catalog: reactivity; image captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q15366 (PCBP2_HUMAN, Poly(rC)-binding protein 2).
- Human Protein Atlas. PCBP2 tissue IHC expression (reliability: Approved).
- Human Protein Atlas. PCBP2 subcellular location (ICC-IF): Localized to the nucleoplasm and cytosol..
- Human Protein Atlas. PCBP2 antibody validation summary (2 antibodies).
- Specific enrichment of the RNA-binding proteins PCBP1 and PCBP2 in chief cells of the murine gastric mucosa. Gene expression patterns : GEP 2014 — PMC4008318.
- MiR-5195-3p targets the PCBP2/PI3K/AKT pathway to inhibit melanoma cell proliferation and migration. Heliyon 2023 — PMC10474410.
- Knockdown of Splicing Complex Protein PCBP2 Reduces Extravillous Trophoblast Differentiation Through Transcript Switching. Frontiers in cell and developmental biology 2021 — PMC8172583.
- PCBP2 inhibits antiviral innate immune responses via the MAVS-mediated signaling pathway in severe fever with thrombocytopenia syndrome. Virus research 2026 — PMC12914862.
- PubMed PMID:7607214 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
- PubMed PMID:16541075 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for PCBP2 (Poly(rC)-binding protein 2). Expected localisation Cytoplasmic in tissue (HPA tissue IHC); nuclear possible (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A02425-2). Validated IHC antibody: A02425-2 at 2-5μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Bronchus (Respiratory epithelial cells); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded mouse brain tissue; fixative not specified (datasheet A02425-2); 2. Fixation: Image fixative and duration unreported (datasheet A02425-2); 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 A02425-2); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A02425-2); 8. Primary antibody: Rabbit anti-PCBP2, 2-5μg/ml (datasheet A02425-2); 9. Primary incubation: Overnight at 4 °C (datasheet A02425-2). Watch for: Fixation: Keep fixation consistent across paraffin sections. (standard IHC practice; not target-specific); Caveat: Presumed off-target staining complicates attribution (HPA tissue IHC); Isoform / epitope: 8 isoforms; epitope coverage is unknown (UniProt); Regulation: No specific expression inducer reported (UniProt). Evidence: UniProt Q15366, HPA tissue IHC · Approved, HPA ICC-IF · nucleoplasm and cytosol., Datasheet A02425-2, PMC10474410, PMC8172583. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/PCBP2/immunohistochemistry-ihc-guide.