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BCAP31 / B-cell receptor-associated protein 31 · IHC design guide
Design Immunohistochemistry for BCAP31
BCAP31 shows ubiquitous cytoplasmic tissue staining, with high signal in Bergmann glia and lung macrophages (HPA tissue IHC). This guide covers fixation, antigen retrieval, controls and scoring for chromogenic IHC on paraffin sections.
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
BCAP31 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 (HPA tissue IHC); ER membrane (UniProt) | |
| Staining pattern | High cytoplasmic staining in Bergmann glia and lung macrophages (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A03767-4) | |
| Positive control | Cerebellum+4 more · see all | |
| Negative control | Heart muscle+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 | Presumed off-target binding may confound scoring (HPA tissue IHC) | |
| Regulation | ER stress redistributes BCAP31 (UniProt) | |
| Isoform / epitope | 2 isoforms; epitope differences are unspecified (UniProt) |
Section 1
Recommended BCAP31 IHC & IF Protocols
Compare the catalog antibody’s IHC-P protocol (datasheet A03767-4) with 2 published BCAP31 IHC protocols (PMC11683684; PMC7055246).
| Sample | Paraffin-embedded human colon cancer tissue; fixative not specified (datasheet A03767-4) |
| Fixation | Image fixative and duration unreported (datasheet A03767-4); 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 A03767-4); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A03767-4) |
| Primary antibody | Rabbit anti-BCAP31, 2-5 μg/ml (datasheet A03767-4) |
| Primary incubation | Overnight at 4 °C (datasheet A03767-4) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet A03767-4) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | BCAP31-positive staining in bergmann glia - cytoplasm/membrane of cerebellum (HPA tissue IHC: High). HPA tissue profile: Ubiquitous cytoplasmic expression. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA pH 8.0 retrieval (datasheet A03767-4); the ESCA protocol used steam-heated citrate for 30 min (PMC11683684).
Section 2
What Is the Expected BCAP31 Staining Pattern?
BCAP31 is an endoplasmic reticulum (ER) membrane protein with three transmembrane segments (UniProt P51572 topology). In paraffin-section IHC, expect predominantly cytoplasmic staining, with stronger signal in cerebellar Bergmann glia and lung macrophages (HPA: ubiquitous cytoplasmic expression; High in both cell types). Use these as reference patterns with care: tissue IHC reliability is Supported, with medium consistency between staining and RNA data and presumed off-target binding disregarded (HPA: tissue IHC reliability).
| Cytoplasmic signal is strongest in Bergmann glia or lung macrophages. | This matches the reported High staining in those cells (HPA: cerebellum and lung IHC). ER-associated cytoplasmic staining is biologically plausible for a three-pass ER membrane protein (UniProt P51572 topology). Score the relevant cells within each tissue; a positive field alone does not establish which cell population stained. |
| Signal appears predominantly nuclear or outlines the plasma membrane. | Treat that compartment pattern as suspect: BCAP31 is assigned to the ER and ER–Golgi intermediate compartment membranes (UniProt P51572 subcellular location), and HPA reports cytoplasmic tissue staining (HPA: tissue IHC profile). Recheck morphology, counterstain and detection controls before interpreting the signal as BCAP31. |
| Strong staining appears in cardiomyocytes, skeletal myocytes or oral squamous cells. | Those cells are reported as Not detected (HPA: heart muscle, skeletal muscle and oral mucosa IHC). Strong signal there raises concern for off-target staining or endogenous detection activity (general IHC practice). It is a warning rather than proof of cross-reactivity, especially given the Supported reliability and disregarded presumed off-target binding (HPA: tissue IHC reliability). |
| Color is spread across the section without discernible cellular boundaries. | A uniform deposit cannot establish the reported cytoplasmic, cell-resolved pattern (HPA: tissue IHC profile). Consider nonspecific background or endogenous detection activity (general IHC practice). Compare a no-primary control and inspect whether the signal remains tied to recognizable cell cytoplasm before assigning a staining level. |
| Bergmann glia or lung macrophages show no detectable signal. | Both are High reference populations (HPA: cerebellum and lung IHC), so absence warrants a technical check before calling the specimen negative. Confirm that the expected cells are present, then review the IHC-validated antibody, retrieval, dilution and detection steps (general IHC practice). These checks do not establish BCAP31-specific fixation sensitivity. |
💡Expected BCAP31 appearanceCall a result positive when recognizable Bergmann glia or lung macrophages show relatively strong cytoplasmic staining consistent with ER localization (HPA: High in both cell types; UniProt P51572 subcellular location); dominant nuclear signal or strong staining in HPA Not detected cells is suspect (HPA: tissue IHC profile).
| Reference-cell choice | Bergmann glia and lung macrophages are High, whereas cardiomyocytes and skeletal myocytes are Not detected (HPA: tissue IHC). Compare identified cell populations rather than whole-section color. HPA also reports ubiquitous cytoplasmic expression, so weak signal elsewhere is not automatically abnormal (HPA: tissue IHC profile). |
| Compartment and epitope location | BCAP31 has three membrane-spanning segments, short lumenal regions and a cytoplasmic region spanning residues 124–246 (UniProt P51572 topology). If an antibody epitope is known, its location can guide interpretation of access after retrieval or permeabilisation (general IHC practice); the supplied record does not identify an epitope or a target-specific retrieval response. |
| Validation strength | Three listed antibodies have Supported IHC status: HPA003906, CAB015350 and CAB015424 (HPA: antibody validation). The tissue profile also has Supported reliability with medium staining–RNA consistency and presumed off-target binding disregarded (HPA: tissue IHC reliability). Resolve an unexpected pattern with controls and morphology rather than treating validation status as absolute specificity. |
| Expression breadth | UniProt describes BCAP31 as ubiquitous and highly expressed in neurons and discrete endocrine cells (UniProt P51572 tissue specificity). HPA reports low tissue specificity and a range from High to Not detected across named cell populations (HPA: tissue IHC). Interpret intensity in the identified cell type; neither source supplies a universal positive cutoff. |
| Situation | Likely cause | Next action |
|---|---|---|
| No signal in a section containing Bergmann glia or lung macrophages. | The result conflicts with High staining reported for those populations (HPA: cerebellum and lung IHC); the cause cannot be identified from pattern alone. | Verify cell identity and section quality, then check the antibody's IHC validation, retrieval, dilution and detection controls (general IHC practice). Do not infer a BCAP31 fixation effect from the HPA staining levels. |
| Strong signal persists in cardiomyocytes or skeletal myocytes. | These populations are Not detected in the tissue profile (HPA: heart muscle and skeletal muscle IHC). Off-target binding or endogenous detection activity is possible (general IHC practice). | Run a no-primary control, inspect cell boundaries and compare with a High reference population (general IHC practice; HPA: lung macrophages and Bergmann glia). Avoid scoring the unexpected signal as confirmed BCAP31. |
| The stain is mostly nuclear or traces cell surfaces. | That distribution conflicts with the reported cytoplasmic tissue pattern and ER localization (HPA: tissue IHC profile; UniProt P51572 subcellular location). | Check counterstain and morphology, then review primary-antibody specificity and detection controls (general IHC practice). Reassess the result in a known High cell population (HPA: lung macrophages or Bergmann glia). |
| Diffuse color obscures differences among cells. | Background deposition can hide a cell-resolved cytoplasmic pattern (general IHC practice; HPA: tissue IHC profile). | Inspect a no-primary control and review blocking, washing and detection conditions (general IHC practice). Score only identifiable cellular signal; HPA's Supported reliability does not validate an obscured section (HPA: tissue IHC reliability). |
| A weak cell population is called negative beside a strong one. | HPA reports Medium staining in several named populations and Low staining in others, alongside High reference populations (HPA: tissue IHC). A single section-wide threshold may conceal that range. | Identify and score each relevant cell population separately, using matched staining conditions and the HPA cell-level categories as context (general IHC practice; HPA: tissue IHC). |
| Q: What should IF/ICC show? | HPA localizes BCAP31 to the ER by ICC-IF, consistent with UniProt's ER membrane assignment (HPA: subcellular ICC-IF; UniProt P51572 subcellular location). | A: Interpret an ER-associated intracellular pattern as consistent with those sources; use the separate IF/ICC guide for experimental setup (HPA: subcellular ICC-IF). |
Experiment evidence
IHC & IF images showing BCAP31 staining
A03767-4 · IHCIHC analysis of BAP31/BCAP31 using anti-BAP31/BCAP31 antibody (A03767-4). BAP31/BCAP31 was detected in a paraffin-embedded section of human
A03767-4 · IHCIHC analysis of BAP31/BCAP31 using anti-BAP31/BCAP31 antibody (A03767-4). BAP31/BCAP31 was detected in a paraffin-embedded section of human
A03767-4 · IFIF analysis of BAP31/BCAP31 using anti-BAP31/BCAP31 antibody (A03767-4). BAP31/BCAP31 was detected in an immunocytochemical section of A549
A03767 · IHCImmunohistochemistry Validation of BAP31 in Rat Lung Tissue Immunohistochemical analysis of paraffin-embedded rat lung tissue using anti-BAP
M03767 · IHCM03767 staining BAP31 in human brain sections by Immunohistochemistry (IHC-P -paraformaldehyde-fixed, paraffin-embedded sections). Tissue wa
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000185825-BCAP31/tissue/cerebral+cortex#imid_1390700
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000185825-BCAP31/tissue/colon#imid_1390618
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000185825-BCAP31/tissue/liver#imid_1390627
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000185825-BCAP31/tissue/kidney#imid_1390636
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody CAB015350; green = BCAP31, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody CAB015350; green = BCAP31, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for BCAP31 IHC & IF
🧪Run lung first and look for staining in macrophages (HPA: High in lung macrophages); use heart muscle cardiomyocytes as the negative tissue (HPA: Not detected in cardiomyocytes). On the lung slide, score unstained non-macrophage cells as internal negatives only after confirming their lack of signal; their negativity is not established by the supplied HPA row (HPA: High in lung macrophages).
Positive control tissue: Cerebellum (Bergmann glia - cytoplasm/membrane, HPA High)
Negative control tissue: Heart muscle (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show BCAP31 in A-431, U-251MG, U2OS, with annotated localisation: Endoplasmic reticulum (enhanced) (HPA subcellular).
Technical controls: Include a no-primary secondary-only control, a rabbit isotype control matched to the primary antibody’s clonality, and a BCAP31 knockout biological negative where available (selected-SKU caption: rabbit primary; standard IHC practice). Check endogenous peroxidase activity in lung macrophages before interpreting DAB signal; for IF, check macrophage autofluorescence with an unstained section (HPA: High in lung macrophages; standard IHC/IF practice).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected-SKU paraffin-section caption does not state a fixative (selected-SKU tissue-IHC caption). The caption reports heat retrieval in EDTA at pH 8.0, but does not establish that retrieval is required under other conditions (selected-SKU tissue-IHC caption). Frozen-section performance and whether IF is easier are unreported; macrophage endogenous peroxidase and autofluorescence warrant controls when using lung (HPA: High in lung macrophages; standard IHC/IF practice).
HPA tissue IHC evidence for BCAP31
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Supported — Medium consistency between antibody staining and RNA expression data. 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 |
|---|---|---|---|---|
| Cerebellum | Bergmann glia - cytoplasm/membrane | High | Protein (IHC) | HPA → |
| Lung | Macrophages | High | Protein (IHC) | HPA → |
| Adipose tissue | Adipocytes | Medium | Protein (IHC) | HPA → |
| Adrenal gland | Glandular cells | Medium | Protein (IHC) | HPA → |
| Appendix | Glandular cells | Medium | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Heart muscle | Cardiomyocytes | Not detected | Protein (IHC) | HPA → |
| Oral mucosa | Squamous epithelial cells | Not detected | Protein (IHC) | HPA → |
| Skeletal muscle | Myocytes | Not detected | Protein (IHC) | HPA → |
| Soft tissue | Peripheral nerve | Not detected | Protein (IHC) | HPA → |
| Vagina | Squamous epithelial cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced BCAP31 IHC Tips
Troubleshoot BCAP31 staining in paraffin sections by checking retrieval, compartment pattern, controls and scoring before interpreting differences between samples.
What retrieval should I use if BCAP31 staining is weak in paraffin sections?
Start with heat-mediated retrieval in EDTA pH 8.0 for this catalog antibody (datasheet A03767-4). Its demonstrated paraffin-section workflow used 2 μg/ml primary antibody overnight at 4°C, so reproduce those conditions before changing retrieval (datasheet A03767-4). If staining remains weak, compare a modestly longer heating step on matched sections while monitoring tissue integrity and background (standard IHC practice). Include a section processed without primary antibody and a reference section in every comparison, because changes in detection or section handling can otherwise resemble improved antigen exposure (standard IHC practice).
How should I troubleshoot BCAP31 staining when fixation history is uncertain?
Target-specific fixation sensitivity is unknown: the selected paraffin-section caption does not state its fixative (datasheet A03767-4). Record the available fixation and processing history, then compare sections with similar handling before attributing different staining intensity to BCAP31 abundance (standard IHC practice). If archival blocks vary, keep section thickness, EDTA pH 8.0 retrieval, primary concentration and detection conditions consistent during the comparison (datasheet A03767-4; standard IHC practice). Evaluate tissue preservation and a reference section alongside each run, since poor morphology or uneven processing can compromise a chromogenic score even when brown signal remains visible (standard IHC practice).
What staining pattern should BCAP31 show, and how do I assess unexpected membrane signal?
Expect a predominantly cytoplasmic, often perinuclear pattern compatible with the endoplasmic reticulum (UniProt P51572 localisation; HPA subcellular: endoplasmic reticulum). BCAP31 is an ER and ER–Golgi intermediate-compartment membrane protein with 3 transmembrane segments, so diffuse cell-surface outlining alone needs independent validation (UniProt P51572 topology and localisation). At tissue scale, HPA describes ubiquitous cytoplasmic expression and reports cytoplasm/membrane staining in Bergmann glia (HPA tissue IHC). Compare the suspected pattern with cell morphology and an adjacent reference section, and check whether the signal persists when primary antibody is omitted before assigning it to BCAP31 (standard IHC practice).
Can this antibody distinguish BCAP31 isoforms or a particular membrane-facing epitope?
BCAP31 has 2 annotated isoforms, but the supplied catalog caption does not map this antibody’s epitope or establish isoform selectivity (UniProt P51572 isoforms; datasheet A03767-4). The annotated topology places residues 28–43 and 124–246 on the cytoplasmic side and residues 2–6 and 65–102 on the lumenal side (UniProt P51572 topology). Retrieval performance therefore cannot identify which side this antibody recognizes (standard IHC interpretation). Consult a verified immunogen or epitope specification before making isoform-specific claims, and interpret staining as BCAP31-associated unless specificity is established by an independent control (standard IHC practice).
How should I adapt BCAP31 localisation checks to multiplex immunofluorescence?
For IF/ICC, compare BCAP31 with an ER marker and a marker identifying the expected cell population; HPA reports ER localisation and high staining in lung macrophages and cerebellar Bergmann glia (HPA subcellular; HPA tissue IHC). Select a fluorophore whose signal can be separated from the specimen’s autofluorescence, and inspect single-channel and no-primary controls before interpreting overlap (standard IF practice). Permeabilisation must allow access to the recognized membrane-facing epitope; BCAP31 has cytoplasmic and lumenal regions, while this antibody’s epitope is unspecified (UniProt P51572 topology; datasheet A03767-4). Optimise that access in the IF specimen itself rather than assuming the paraffin-section retrieval conditions apply (standard IF practice).
How do I reduce widespread brown background without losing BCAP31 signal?
First distinguish cellular cytoplasmic staining from diffuse deposit, section-edge staining and pigment by examining morphology and a no-primary control (HPA tissue IHC profile; standard IHC practice). The documented paraffin-section workflow used 10% goat serum, 2 μg/ml primary antibody overnight at 4°C, and DAB development (datasheet A03767-4). Apply a peroxidase block, adequate washes and consistent chromogen exposure, then adjust primary concentration only after comparing matched sections (standard chromogenic IHC practice). Widespread signal alone is weak evidence of specificity because BCAP31 is broadly expressed and the HPA tissue assessment notes presumed off-target binding (UniProt P51572 tissue specificity; HPA tissue IHC reliability).
How should I score BCAP31 staining across paraffin sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and cytoplasmic compartment before scoring, since HPA describes ubiquitous cytoplasmic staining with differing levels among cell types (HPA tissue IHC). Use an H-score based on the percentage of cells at each intensity, or report percent-positive cells with the same prespecified threshold across sections (standard IHC practice). For spatial comparisons, report positive-cell density per mm² of viable tissue and normalise counts to the annotated viable area and relevant cell population (standard IHC practice). Keep retrieval, detection, imaging and counterstain settings consistent, and exclude necrosis, folds and section edges from the scored region (standard IHC practice).
When is BCAP31 staining convincing rather than artefactual?
A convincing result follows cellular cytoplasmic or perinuclear morphology compatible with BCAP31’s ER localisation and appears in an appropriate cell population (UniProt P51572 localisation; HPA tissue IHC). Lung macrophages and cerebellar Bergmann glia are reported as high-staining examples, but HPA rates tissue evidence as Supported and notes presumed off-target binding (HPA tissue IHC). Treat isolated nuclear staining, sharp section-edge signal, necrotic deposits and brown signal reproduced without primary antibody as reasons to investigate rather than proof of BCAP31 expression (standard IHC practice). Check endogenous peroxidase with the appropriate control, then compare the pattern and intensity with tissue morphology and a reference section before drawing biological conclusions (standard chromogenic IHC practice).
Boster reagents
Best BCAP31 / B-cell receptor-associated protein 31 IHC Antibodies
The catalog includes BCAP31 antibodies with IHC images from human colon cancer, rat lung and human brain sections (catalog image captions), plus IF images from human tissue and A549 cells (A03767-4 IF captions).
Real IHC data
Anti-BAP31/BCAP31 Antibody ®
Cat # A03767-4
Real IHC data
Anti-BAP31 BCAP31 Antibody
Cat # A03767
Real IHC data
Anti-BAP31 Antibody
Cat # M03767
A03767-4 shows IHC in human colon cancer sections and IF in A549 cells and human tissue (A03767-4 image captions). A03767 shows IHC in rat lung, while M03767 shows IHC in human brain sections (A03767 and M03767 image captions).
Which to pick: For human paraffin-section IHC, choose A03767-4 at 2–5 μg/ml (datasheet: IHC dilution; A03767-4 IHC caption: human colon cancer); its IHC caption does not report the fixative (A03767-4 IHC caption). For IF/ICC, choose A03767-4 at 5 μg/ml (datasheet: IF/ICC application and dilution; A03767-4 IF captions: A549 cells and human tissue). For rat tissue IHC, A03767 has a rat lung example at 2 μg/mL (A03767 IHC caption); it lists human, mouse and rat reactivity, but its IHC validation is in rat samples (A03767 catalog reactivity and validation).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P51572 (BAP31_HUMAN, B-cell receptor-associated protein 31).
- Human Protein Atlas. BCAP31 tissue IHC expression (reliability: Supported).
- Human Protein Atlas. BCAP31 subcellular location (ICC-IF): Localized to the endoplasmic reticulum..
- Human Protein Atlas. BCAP31 antibody validation summary (3 antibodies).
- Pan-cancer analysis shows that BCAP31 is a potential prognostic and immunotherapeutic biomarker for multiple cancer types. Frontiers in immunology 2024 — PMC11683684.
- BCAP31 drives TNBC development by modulating ligand-independent EGFR trafficking and spontaneous EGFR phosphorylation. Theranostics 2019 — PMC6771250.
- BCAP31, a cancer/testis antigen-like protein, can act as a probe for non-small-cell lung cancer metastasis. Scientific reports 2020 — PMC7055246.
- A novel BCAP31 variant associated with nonsyndromic auditory neuropathy spectrum disorder: mitochondrial dysfunction, cisplatin sensitivity, and amenability to mitochondrial transplantation. Journal of translational medicine 2025 — PMC12131585.
- PubMed PMID:7806238 — UniProt-cited evidence.
- PubMed PMID:8706661 — UniProt-cited evidence.
- PubMed PMID:8612576 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for BCAP31 (B-cell receptor-associated protein 31). Expected localisation Cytoplasmic (HPA tissue IHC); ER membrane (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A03767-4). Validated IHC antibody: A03767-4 at 2-5 μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Cerebellum (Bergmann glia - cytoplasm/membrane); negative Heart muscle. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human colon cancer tissue; fixative not specified (datasheet A03767-4); 2. Fixation: Image fixative and duration unreported (datasheet A03767-4); 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 A03767-4); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A03767-4); 8. Primary antibody: Rabbit anti-BCAP31, 2-5 μg/ml (datasheet A03767-4); 9. Primary incubation: Overnight at 4 °C (datasheet A03767-4). Watch for: Fixation: Keep fixation consistent across sections (standard IHC practice; not target-specific); Caveat: Presumed off-target binding may confound scoring (HPA tissue IHC); Isoform / epitope: 2 isoforms; epitope differences are unspecified (UniProt); Regulation: ER stress redistributes BCAP31 (UniProt). Evidence: UniProt P51572, HPA tissue IHC · Supported, HPA ICC-IF · endoplasmic reticulum., Datasheet A03767-4, PMC11683684, PMC7055246. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/BCAP31/immunohistochemistry-ihc-guide.