This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
BTN3A1 / Butyrophilin subfamily 3 member A1 · IHC design guide
Design Immunohistochemistry for BTN3A1
Plan BTN3A1 chromogenic IHC in paraffin sections using the observed cytoplasmic tissue pattern (HPA tissue IHC). Compare positive tissue compartments with controls and account for the catalog antibody’s BTN3A1/2/3 target range (datasheet: A04257).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
BTN3A1 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 tissue staining (HPA tissue IHC); membrane topology (UniProt) | |
| Staining pattern | Cytoplasmic staining in several tissue cell types (HPA tissue IHC) | |
| Antigen retrieval | Citrate pH 6.0 HIER, 95–98 °C, 20 min (rule: cytoplasmic / membrane antigen) | |
| Positive control | Adrenal gland+4 more · see all | |
| Negative control | Adipose tissue+4 more · see all |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image A04257) | |
| Caveat | Catalog antibody targets BTN3A1/2/3 (datasheet: A04257) | |
| Regulation | Stimulus-linked abundance unreported (UniProt) | |
| Isoform / epitope | 4 isoforms; check extracellular versus cytoplasmic epitope (UniProt) |
Section 1
Recommended BTN3A1 IHC & IF Protocols
The catalog antibody IHC-P protocol is accompanied by four published BTN3A1 IHC workflows (PMC11165028; PMC9772689; PMC8409294; PMC13458587).
| Sample | Paraffin-embedded human kidney tissue; fixative not specified (datasheet A04257) |
| Fixation | Image fixative and duration unreported (datasheet A04257); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat-induced epitope retrieval in citrate buffer, pH 6.0, 20 min at 95–98 °C (standard rule: cytoplasmic / membrane antigen) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% normal serum of the secondary host, 30 min, room temperature (standard) |
| Primary antibody | Rabbit anti-BTN3A1, 1:50 recommended; image 1:200 (datasheet A04257) |
| Primary incubation | Overnight at 4 °C (standard) |
| Detection | HRP-polymer secondary, DAB chromogen 5–10 min (standard) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | BTN3A1-positive staining in glandular cells of adrenal gland (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression in several tissues. No signal in the no-primary control. |
💡Decision noteStart with citrate pH 6.0 retrieval at 95–98 °C for 20 min (page antigen retrieval); adjust for the antibody and sample used.
Section 2
What Is the Expected BTN3A1 Staining Pattern?
BTN3A1 is a cell membrane protein with one transmembrane segment (UniProt O00481 topology). In tissue IHC, HPA reports cytoplasmic staining in several tissues, including high staining in glandular cells and kidney tubule cells (HPA tissue IHC: High). HPA rates the tissue staining Approved, with medium consistency between antibody staining and RNA expression (HPA tissue IHC: Approved).
| Cytoplasmic staining in colon glandular cells or kidney tubule cells. | This matches high staining reported for these cells (HPA tissue IHC: High). Score the named cells and their compartment; surrounding unstained cells alone do not invalidate the result. Cytoplasmic IHC staining can coexist with BTN3A1's annotated membrane topology (UniProt O00481 topology). |
| Predominantly nuclear staining, with little staining in expected positive cells. | Nuclear localization is not the annotated membrane location or the reported tissue IHC profile (UniProt O00481; HPA tissue IHC: cytoplasmic). Treat this as a suspect pattern and check antibody specificity, detection controls, and slide morphology before scoring it as BTN3A1. |
| Strong staining in adipocytes or cardiomyocytes while positive reference cells are unstained. | HPA reports BTN3A1 as not detected in those cell types and high in several glandular cell populations (HPA tissue IHC). Investigate cross-reactivity or endogenous detection activity. A negative HPA observation is a reference for interpretation, not proof that every specimen must be negative. |
| Similar diffuse color across cells, stroma, and empty areas. | A uniform deposit that does not follow cell boundaries or the reported cytoplasmic pattern is difficult to assign to BTN3A1 (HPA tissue IHC: cytoplasmic). Check a no-primary control and the detection steps for nonspecific background (standard IHC practice). |
| No staining in a well-preserved colon or kidney positive reference section. | HPA reports high staining in colon glandular cells and kidney tubule cells (HPA tissue IHC: High). First verify that the reference contains those cells; then review the antibody, retrieval, detection, and counterstain workflow (standard IHC practice). One negative run does not establish absence of BTN3A1. |
💡Expected BTN3A1 appearanceA convincing positive shows discernible cytoplasmic staining in the relevant glandular or kidney tubule cells, potentially high in HPA positive references; isolated nuclear color or uniform background is suspect (HPA tissue IHC: cytoplasmic, High; UniProt O00481: cell membrane).
| Topology and observed compartment | BTN3A1 has an extracellular region at 30–254, a membrane span at 255–271, and a cytoplasmic region at 272–513 (UniProt O00481 topology). HPA nevertheless describes tissue IHC as cytoplasmic; do not require a crisp surface rim to call a tissue section positive (HPA tissue IHC). |
| Choice of reference cells | HPA reports high staining in adrenal, appendix, colon, endometrial, and gallbladder glandular cells, kidney tubule cells, lymph node non-germinal center cells, and ovarian follicle cells (HPA tissue IHC: High). Select and score a documented cell population within the reference section. |
| Weak and negative reference patterns | Lung macrophages and several other listed cell populations have low staining, while adipocytes and cardiomyocytes are reported as not detected (HPA tissue IHC). These are less suitable as sole positive controls; compare the specified cell types rather than assigning one status to an entire tissue. |
| Evidence and antibody scope | The tissue IHC profile is Approved with medium staining–RNA consistency, and the listed antibody HPA012565 is IHC Approved (HPA tissue IHC; HPA antibodies). That supports a reference pattern, but does not validate an unrelated catalog antibody or every cell in every specimen. |
| IF interpretation | HPA reports mainly vesicular localization in ICC-IF, marked uncertain, and rates HPA012565 ICC Uncertain (HPA subcellular; HPA antibodies). Use those images as a tentative localization comparison; the tissue IHC profile supplies the primary interpretation for this paraffin-section guide. |
| Isoforms and epitope coverage | UniProt lists 4 BTN3A1 isoforms and a mature chain spanning residues 30–513 (UniProt O00481). No antibody epitope is supplied here, so these facts cannot establish which isoforms a given stain detects or explain a failed stain. |
| Situation | Likely cause | Next action |
|---|---|---|
| The positive reference has no visible signal. | The expected cell population may be absent from the examined field, or an IHC workflow step may have failed (HPA tissue IHC: High reference cells; standard IHC practice). | Confirm the glandular or tubule cells on the section, then review primary antibody use, antigen retrieval, detection reagents, and chromogen development (standard IHC practice). |
| A nuclear signal dominates the section. | That compartment conflicts with the annotated membrane location and reported cytoplasmic tissue pattern (UniProt O00481; HPA tissue IHC). | Compare with a positive reference and no-primary control; assess morphology and detection background before interpreting the nuclear deposit as target staining (standard IHC practice). |
| Adipocytes or cardiomyocytes stain strongly. | Those cells are reported as not detected in HPA tissue IHC; cross-reactivity or endogenous detection activity is possible (HPA tissue IHC; standard IHC practice). | Check a no-primary control, inspect whether staining follows the cells, and compare with an HPA high reference cell population (standard IHC practice; HPA tissue IHC: High). |
| Color is diffuse across the section. | Nonspecific antibody binding or detection background can obscure cellular staining (standard IHC practice). A uniform haze does not match the reported cytoplasmic profile (HPA tissue IHC). | Check the no-primary control and blocking, washing, and detection steps; score BTN3A1 only where cellular morphology and a distinct staining pattern remain interpretable (standard IHC practice). |
| Lung macrophages appear faint beside a strong glandular reference. | HPA assigns lung macrophages a low level and several glandular populations a high level (HPA tissue IHC). The difference alone does not indicate a failed assay. | Compare the same named cell types across sections and use an HPA high population to judge whether the staining run worked (HPA tissue IHC; standard IHC practice). |
| ICC-IF vesicles seem inconsistent with tissue IHC cytoplasm. | The vesicular ICC-IF location is marked uncertain, while HPA describes the tissue IHC pattern as cytoplasmic (HPA subcellular; HPA tissue IHC). | Interpret each preparation against its own HPA observation; use the tissue IHC profile for paraffin-section scoring and treat vesicular IF localization as tentative (HPA tissue IHC; HPA subcellular). |
Experiment evidence
IHC & IF images showing BTN3A1 staining
A04257 · IHCImmunohistochemical analysis of paraffin-embedded human-kidney, antibody was diluted at 1:200.
A04257 · IHCImmunohistochemical analysis of paraffin-embedded human-kidney, antibody was diluted at 1:200.
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000026950-BTN3A1/tissue/cerebral+cortex#imid_4579656
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000026950-BTN3A1/tissue/colon#imid_4579598
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000026950-BTN3A1/tissue/liver#imid_4579599
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000026950-BTN3A1/tissue/kidney#imid_4579600
HPA · ICC-IF U-251MGHuman Protein Atlas immunofluorescence, U-251MG, antibody HPA012565; green = BTN3A1, blue = nucleus, red = microtubules.
HPA · ICC-IF U-251MGHuman Protein Atlas immunofluorescence, U-251MG, antibody HPA012565; green = BTN3A1, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for BTN3A1 IHC & IF
🧪Run colon first and score its glandular cells for staining (HPA: High in colon glandular cells); use adipose tissue adipocytes as the negative comparison (HPA: Not detected in adipose tissue adipocytes). No negative cell population within the colon section is established by the supplied HPA rows, so treat any unstained neighboring cells as a background reference rather than a validated internal negative.
Positive control tissue: Adrenal gland (Glandular cells, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show BTN3A1 in U-251MG, U2OS, with annotated localisation: Vesicles (uncertain) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control; an irrelevant isotype control matched to the primary antibody’s host species and, for a monoclonal antibody, its isotype; and a BTN3A1 knockout or validated peptide-block control (standard IHC practice). Quench endogenous peroxidase before chromogenic detection, particularly when assessing inflammatory cells in colon (standard IHC practice).
⚠️Feasibility: A target-specific fixation window and retrieval dependency are unreported in the supplied evidence; optimize retrieval empirically for paraffin sections (standard IHC practice). The selected A04257 caption shows paraffin-embedded kidney stained at 1:200, but its fixative is unreported (selected-SKU tissue-IHC caption). No matched evidence establishes that frozen sections or IF are easier for BTN3A1; in colon, inflammatory-cell peroxidase can complicate chromogenic interpretation (standard IHC practice).
HPA tissue IHC evidence for BTN3A1
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 |
|---|---|---|---|---|
| Adrenal gland | Glandular cells | High | Protein (IHC) | HPA → |
| Appendix | Glandular cells | High | Protein (IHC) | HPA → |
| Colon | Glandular cells | High | Protein (IHC) | HPA → |
| Endometrium | Glandular cells | High | Protein (IHC) | HPA → |
| Gallbladder | Glandular cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Breast | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Caudate | Glial cells | Not detected | Protein (IHC) | HPA → |
| Cervix | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Epididymis | Glandular cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced BTN3A1 IHC Tips
Troubleshoot BTN3A1 staining in paraffin section chromogenic IHC, using the catalog antibody’s kidney image and independent localisation evidence as reference points.
How should I retrieve BTN3A1 when staining is weak?
Use citrate buffer at pH 6.0 for heat induced antigen retrieval at 95–98 °C for 20 min (page retrieval rule). The selected catalog antibody has a paraffin embedded human kidney IHC image at 1:200, but its caption does not report the retrieval method (catalog antibody A04257 caption). If signal is weak, compare retrieved and untreated serial sections, then adjust heating within a controlled pilot while keeping antibody dilution and detection constant (standard IHC practice). Score tubular cells against adjacent background because kidney tubular cells show high staining in the independent tissue profile (HPA: high in kidney tubular cells).
How do I assess whether fixation is masking BTN3A1?
BTN3A1 specific fixation sensitivity is unknown: the selected paraffin section caption does not state a fixative (catalog antibody A04257 caption). Record the actual fixative, fixation duration, section age and processing history for each block before comparing staining (standard IHC practice). On serial sections, hold the catalog antibody at its documented 1:200 dilution and apply the page’s citrate pH 6.0, 95–98 °C, 20 min retrieval consistently (catalog antibody A04257 caption; page retrieval rule). Include kidney tubular cells as a tissue reference and compare them only across similarly processed sections, since processing differences can change staining independently of antigen abundance (HPA: high in kidney tubular cells; standard IHC practice).
Should BTN3A1 stain membranes or cytoplasm in tissue sections?
Expect BTN3A1 at the cell membrane based on its single transmembrane segment at residues 255–271, with extracellular residues 30–254 and cytoplasmic residues 272–513 (UniProt O00481 topology). Tissue IHC also reports cytoplasmic staining in several tissues, while cell imaging places it mainly in vesicles with uncertain localisation (HPA tissue IHC: cytoplasmic expression; HPA subcellular: vesicles, uncertain). In chromogenic sections, record membrane and cytoplasmic staining separately instead of treating either compartment as automatic proof of specificity (standard IHC practice). Compare the pattern within kidney tubular cells, a high staining reference, and flag diffuse nuclear staining for control based review (HPA: high in kidney tubular cells; UniProt O00481 topology; standard IHC practice).
How can epitope placement change BTN3A1 IHC interpretation?
Map the antibody’s disclosed immunogen to BTN3A1 before interpreting absent or compartment restricted staining; the supplied caption does not identify its epitope (catalog antibody A04257 caption). BTN3A1 has 4 reported isoforms, an extracellular region at residues 30–254, and a cytoplasmic region at 272–513 (UniProt O00481 isoforms and topology). Its extracellular region includes two Ig like domains and a glycosylation site at residue 115, while the B30.2/SPRY domain spans 322–513 (UniProt O00481 domains and glycosylation). Check whether the disclosed sequence is shared across relevant isoforms, then validate staining with an independent epitope or orthogonal expression measure when available (standard IHC practice).
How should I cross check BTN3A1 by multiplex IF?
Use IF as a separate validation experiment and compare its cellular pattern with the chromogenic section; the selected caption documents paraffin section IHC only (catalog antibody A04257 caption). Pair BTN3A1 with a validated marker for the expected cell population, such as a macrophage marker in lung, where macrophage staining is reported as low (HPA: low in lung macrophages; standard IF practice). Choose fluorophores in channels with low measured tissue autofluorescence, and include single stain controls for spectral separation (standard IF practice). Decide permeabilisation after identifying the antibody epitope: intracellular epitopes require access through the membrane, whereas an extracellular epitope can be assessed without that access (UniProt O00481 topology; standard IF practice).
What should I check when BTN3A1 chromogenic staining looks widespread?
Run a no primary control and inspect the same compartment and cell type as the apparent BTN3A1 signal (standard IHC practice). Block endogenous peroxidase before HRP and DAB detection, and examine pigment or precipitate that can resemble brown staining (standard IHC practice). Keep the antibody at the captioned 1:200 starting dilution while comparing controls, then titrate only if the signal to background ratio requires it (catalog antibody A04257 caption; standard IHC practice). Because the tissue profile describes cytoplasmic expression across several tissues and low tissue specificity, widespread cytoplasmic color alone is insufficient evidence of a specific signal (HPA tissue IHC: cytoplasmic expression; HPA RNA: low tissue specificity).
How should I score BTN3A1 across heterogeneous sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and compartment before scoring, then report percent positive cells and staining intensity or calculate an H score from intensity categories (standard IHC practice). For sparse infiltrating cells, report positive cells per mm² of viable tissue and state how the analyzed area was selected (standard IHC practice). Normalize epithelial results to the number of eligible epithelial cells and immune cell results to their identified population, rather than pooling all nuclei (standard IHC practice). Score membrane and cytoplasmic signals separately because BTN3A1 is a membrane protein while tissue IHC reports cytoplasmic expression; use kidney tubular cells as a high staining reference across comparable runs (UniProt O00481 topology; HPA tissue IHC: cytoplasmic expression and high in kidney tubular cells).
Which BTN3A1 patterns are credible, and which suggest artefact?
A credible pattern should recur in comparable sections and align with a plausible compartment and cell population: BTN3A1 is membrane associated, while tissue IHC reports cytoplasmic staining and high signal in kidney tubular cells (UniProt O00481 topology; HPA tissue IHC: cytoplasmic expression and high in kidney tubular cells). Its protein has also been detected on T cells, natural killer cells, dendritic cells and macrophages, so identify immune cells before assigning their staining to nearby epithelium (UniProt O00481 tissue specificity; standard IHC practice). Treat isolated nuclear color, section edge accentuation and necrotic areas as suspect until controls support them (UniProt O00481 topology; standard IHC practice). Exclude endogenous peroxidase signal with a no primary control and a peroxidase block before interpreting DAB deposits (standard IHC practice).
Boster reagents
Best BTN3A1 / Butyrophilin subfamily 3 member A1 IHC Antibodies
A04257 is a human-reactive anti-BTN3A1/2/3 antibody listed for IHC and IF (catalog: reactivity Human; applications IHC, IF). Its figure shows paraffin-embedded human kidney (A04257 image caption).
Real IHC data
Anti-BTN3A1/2/3 Antibody
Cat # A04257
A04257 will render with an IHC figure of paraffin-embedded human kidney stained at 1:200 (A04257 image caption). IF is a listed application, but no IF figure is supplied (catalog: applications IF, IHC; IF image alts empty).
Which to pick: For tissue IHC, choose A04257 for human paraffin sections; its own figure shows human kidney at 1:200, and the fixative is unreported (A04257 image caption). For IF, A04257 is listed for human samples, but ICC-specific validation is unreported (catalog: reactivity Human; applications IF, IHC). No cross-species option is documented (catalog: reactivity Human only).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry O00481 (BT3A1_HUMAN, Butyrophilin subfamily 3 member A1).
- Human Protein Atlas. BTN3A1 tissue IHC expression (reliability: Approved).
- Human Protein Atlas. BTN3A1 subcellular location (ICC-IF): Mainly localized to vesicles..
- Human Protein Atlas. BTN3A1 antibody validation summary (1 antibodies).
- High expression of BTN3A1 is associated with clinical and immunological characteristics and predicts a poor prognosis in advanced human gliomas. Frontiers in immunology 2024 — PMC11165028.
- Targeting of colorectal cancer organoids with zoledronic acid conjugated to the anti-EGFR antibody cetuximab. Journal for immunotherapy of cancer 2022 — PMC9772689.
- Comprehensive analysis of BTN3A1 in cancers: mining of omics data and validation in patient samples and cellular models. FEBS open bio 2021 — PMC8409294.
- Metformin sensitizes esophageal squamous cell carcinoma to Vγ9Vδ2 T cell-mediated cytotoxicity by upregulating BTN3A1 and BTN2A1. Cell death & disease 2026 — PMC13458587.
- PubMed PMID:9382921 — UniProt-cited evidence.
- PubMed PMID:9149941 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for BTN3A1 (Butyrophilin subfamily 3 member A1). Expected localisation Cytoplasmic tissue staining (HPA tissue IHC); membrane topology (UniProt). Antigen retrieval: Citrate pH 6.0 HIER, 95–98 °C, 20 min (rule: cytoplasmic / membrane antigen). Validated IHC antibody: A04257 at 1:50 recommended; image 1:200 (the product's own IHC validation image is shown). Controls (HPA): positive Adrenal gland (Glandular cells); negative Adipose tissue. IHC workflow; specimen preparation unspecified. Protocol steps: 1. Sample: Paraffin-embedded human kidney tissue; fixative not specified (datasheet A04257); 2. Fixation: Image fixative and duration unreported (datasheet A04257); 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-induced epitope retrieval in citrate buffer, pH 6.0 , 20 min at 95–98 °C…; 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% normal serum of the secondary host, 30 min , room temperature (standard); 8. Primary antibody: Rabbit anti-BTN3A1, 1:50 recommended; image 1:200 (datasheet A04257); 9. Primary incubation: Overnight at 4 °C (standard). Watch for: Fixation: Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image A04257); Caveat: Catalog antibody targets BTN3A1/2/3 (datasheet: A04257); Isoform / epitope: 4 isoforms; check extracellular versus cytoplasmic epitope (UniProt); Regulation: Stimulus-linked abundance unreported (UniProt). Evidence: UniProt O00481, HPA tissue IHC · Approved, HPA ICC-IF · Mainly localized to vesicles., Datasheet A04257, PMC11165028, PMC9772689. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/BTN3A1/immunohistochemistry-ihc-guide.