This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
SFRP1 / Secreted frizzled-related protein 1 · IHC design guide
Design Immunohistochemistry for SFRP1
Plan SFRP1 paraffin-section IHC around extracellular staining and a high-staining testis control with pachytene spermatocytes (HPA tissue IHC). The catalog antibody A01968-2 has an IHC working range of 0.5–1 μg/mL (datasheet).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
SFRP1 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 | Extracellular tissue staining (HPA tissue IHC) | |
| Staining pattern | Extracellular positivity in several tissues (HPA tissue IHC) | |
| Antigen retrieval | Citrate pH 6 HIER, heat-mediated (datasheet A01968-2) | |
| Positive control | Testis | |
| Negative control | Adipose tissue+4 more · see all |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep fixation conditions consistent across sections. (standard IHC practice; not target-specific) | |
| Caveat | Secreted SFRP1 may stain away from producing cells (UniProt) | |
| Regulation | Tissue-dependent expression (UniProt) | |
| Isoform / epitope | No isoforms annotated; mature chain spans aa 32–314 (UniProt) |
Section 1
Recommended SFRP1 IHC & IF Protocols
The catalog antibody’s IHC-P protocol is followed by published SFRP1 staining methods for large bowel, breast, prostate, and oral specimens (PMC2361362; PMC7565692; PMC4342152; PMC4610781).
| Sample | Paraffin-embedded human colon cancer tissue; fixative not specified (datasheet A01968-2) |
| Fixation | Image fixative and duration unreported (datasheet A01968-2); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: Citrate pH 6, 20 min (datasheet A01968-2) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A01968-2) |
| Primary antibody | Rabbit anti-SFRP1, 0.5-1μg/ml (datasheet A01968-2) |
| Primary incubation | Overnight at 4 °C (datasheet A01968-2) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet A01968-2) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | SFRP1-positive staining in pachytene spermatocytes of testis (HPA tissue IHC: High). HPA tissue profile: extracellular positivity in several tissues. No signal in the no-primary control. |
💡Decision noteStart with citrate pH 6 heat retrieval for the catalog antibody (datasheet A01968-2). The breast TMA study used Tris-EGTA pH 9 retrieval (PMC7565692 methods).
Section 2
What Is the Expected SFRP1 Staining Pattern?
SFRP1 is secreted and may remain associated with the cell surface or extracellular matrix; it has no transmembrane segment (UniProt Q8N474 topology). In paraffin sections, expect extracellular staining in several tissues and strong staining associated with pachytene spermatocytes in testis (HPA: Approved tissue IHC; High in pachytene spermatocytes). Because secreted protein can move from its producing cells, the site of staining need not match the site of RNA expression (HPA: tissue IHC reliability note).
| Extracellular staining near pachytene spermatocytes, with a strong signal in testis. | This fits the reported extracellular tissue profile and high testis staining (HPA: extracellular positivity; High in pachytene spermatocytes). Record the stained compartment as well as the associated cell type; secreted SFRP1 may be retained outside cells (UniProt Q8N474 subcellular location). |
| Predominantly crisp nuclear staining, especially without extracellular signal. | Treat this as unexpected: SFRP1 is secreted and has no transmembrane segment (UniProt Q8N474 topology). Nuclear color alone does not establish SFRP1 localisation. Compare with a known-positive testis section and a detection control before interpreting it as specific staining (HPA: High in pachytene spermatocytes; standard IHC practice). |
| Strong staining confined to a cell population reported as undetected, such as adipocytes in adipose tissue. | This conflicts with that specific HPA observation (HPA: Not detected in adipose-tissue adipocytes). Check morphology, antibody specificity and endogenous chromogen-generating activity. A negative call for one cell population does not make every structure in that tissue a validated negative control (HPA: cell-specific tissue IHC results). |
| Weak, widespread color across cells, matrix and empty areas of the section. | A uniform haze is difficult to reconcile with the reported extracellular pattern and distinct high testis signal (HPA: extracellular positivity; High in pachytene spermatocytes). Assess background with a no-primary control, then review blocking, washes, antibody concentration and chromogen development (standard IHC practice). |
| No convincing staining in a testis section containing pachytene spermatocytes. | The result fails to reproduce the supplied positive reference (HPA: High in pachytene spermatocytes). First confirm the relevant cells are present; then check that detection reagents work and review the antibody, retrieval and dilution conditions (standard IHC practice). HPA supplies no target-specific fixation-sensitivity finding. |
💡Expected SFRP1 appearanceCall a section positive when staining is extracellular or cell-associated around pachytene spermatocytes, with a high testis signal; isolated crisp nuclear staining or uniform haze is suspect (HPA: extracellular positivity; High in pachytene spermatocytes; UniProt Q8N474 topology).
| Secretion and retention | SFRP1 is secreted but may associate with cell membranes or extracellular matrix and can be released by heparin binding (UniProt Q8N474 subcellular location). Interpret a pericellular or matrix deposit in anatomical context; staining need not sit entirely inside the producing cell (HPA: secreted-protein reliability note). |
| Processing and domain location | The annotated signal peptide spans residues 1–31; the mature chain spans 32–314, with FZ and NTR domains (UniProt Q8N474 processing and domains). Epitope position is not supplied for CAB008116, so these annotations cannot predict whether that antibody detects a particular processed form (HPA: CAB008116 listing). |
| Antibody evidence | CAB008116 is listed as rabbit polyclonal with IHC status Approved; ICC status is not supplied (HPA: antibody validation). Approved describes the reported IHC evidence; it should not be presented as Enhanced or as independent confirmation of every compartment or tissue result (HPA: validation status). |
| IF/ICC Q&A: what localisation is established? | No HPA ICC-IF main location or cell-line images are available (HPA: subcellular record). Extracellular or pericellular signal is biologically plausible from secretion and matrix association (UniProt Q8N474 subcellular location), but a specific IF/ICC staining pattern is unverified here. Use the separate IF/ICC guide for that application. |
| Situation | Likely cause | Next action |
|---|---|---|
| Testis positive control is blank. | The reference signal is not reproduced, or the section lacks identifiable pachytene spermatocytes (HPA: High in pachytene spermatocytes). | Verify the cell population and run a functioning detection control; review the antibody's IHC conditions, retrieval and dilution as general workflow variables (standard IHC practice). No SFRP1-specific retrieval or fixation effect is established here. |
| Adipose-tissue adipocytes stain strongly. | Those cells were reported as not detected; nonspecific antibody binding or endogenous detection activity is possible (HPA: Not detected in adipose-tissue adipocytes; standard IHC practice). | Confirm adipocyte identity, compare a no-primary control, and assess the detection-system block (standard IHC practice). Interpret other structures separately; the HPA negative designation applies to the listed cells. |
| Signal is nuclear with little extracellular color. | That distribution conflicts with the secreted annotation and reported extracellular tissue profile (UniProt Q8N474 topology; HPA: tissue IHC profile). | Check the testis positive control and no-primary control, then reassess morphology and antibody specificity before scoring the nuclear signal (HPA: High in pachytene spermatocytes; standard IHC practice). |
| Brown haze obscures tissue boundaries. | Excess antibody, incomplete washing or prolonged chromogen development can raise general IHC background (standard IHC practice). | Use a no-primary control to locate detection background; adjust blocking, washes, antibody concentration or development time one variable at a time (standard IHC practice). Preserve extracellular deposits that follow tissue structure (HPA: extracellular positivity). |
| Staining varies between cells and adjacent extracellular space. | Secreted SFRP1 may remain membrane or matrix-associated, so intracellular and extracellular distributions need careful separation (UniProt Q8N474 subcellular location). | Score cell-associated and extracellular signal separately, using tissue morphology and the testis reference (HPA: extracellular positivity; High in pachytene spermatocytes). Do not infer the producing cell solely from the location of a deposit (HPA: secreted-protein reliability note). |
| An IF/ICC image lacks a clear matching pattern. | The supplied subcellular record has no main location or ICC-IF images, and CAB008116 has no stated ICC validation (HPA: subcellular record; antibody listing). | Treat the IF/ICC result as unverified by these sources; assess it within the separate IF/ICC guide. Do not use the IHC Approved status as an IF/ICC validation claim (HPA: CAB008116 IHC Approved; ICC status not supplied). |
Experiment evidence
IHC & IF images showing SFRP1 staining
A01968-2 · IHCIHC analysis of SFRP1 using anti-SFRP1 antibody (A01968-2). SFRP1 was detected in paraffin-embedded section of human colon cancer tissue. He
A01968-2 · IHCIHC analysis of SFRP1 using anti-SFRP1 antibody (A01968-2). SFRP1 was detected in paraffin-embedded section of human lung cancer tissue. Hea
A01968-2 · IFIF analysis of SFRP1 using anti-SFRP1 antibody (A01968-2). SFRP1 was detected in immunocytochemical section of U20S cells. Enzyme antigen re
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000104332-SFRP1/tissue/cerebral+cortex#imid_2241216
HPA · Salivary glandHuman Protein Atlas IHC, Salivary gland. Source: https://www.proteinatlas.org/ENSG00000104332-SFRP1/tissue/salivary+gland#imid_2241164
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000104332-SFRP1/tissue/colon#imid_2237782
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000104332-SFRP1/tissue/liver#imid_2237783
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for SFRP1 IHC & IF
🧪Run testis first and expect staining in pachytene spermatocytes (HPA: High in pachytene spermatocytes). Use adipose tissue adipocytes as a negative comparator (HPA: Not detected in adipocytes); on the testis slide, cells lacking specific staining provide an internal negative reference, but the supplied HPA row does not identify them by type.
Positive control tissue: Testis (Pachytene spermatocytes, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA carries no ICC-IF cell line for SFRP1; derive a cell-line control from the positive tissue's cell type (Pachytene spermatocytes) and confirm it by RNA or western blot first.
Technical controls: Include a no-primary, secondary-only control and a species-matched rabbit IgG isotype control alongside a SFRP1 knockout biological negative (caption: rabbit primary antibody). Check endogenous peroxidase and biotin background in testis because the reported detection uses biotinylated secondary antibody, SABC and DAB (caption: SABC/DAB detection).
⚠️Feasibility: The selected-SKU paraffin-section caption does not report a fixative, and no target-specific fixation window or fixation effect is reported in the supplied evidence (caption: fixative unreported). Citrate retrieval at pH 6 for 20 minutes was used, but retrieval dependency is unreported (caption: citrate retrieval). There is no matched evidence that frozen sections or IF are easier; assess testis background from the biotin-based detection system with the controls above (caption: SABC/DAB detection).
HPA tissue IHC evidence for SFRP1
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Approved — At least one protein variant secreted, tissue location of RNA and protein might differ and correlation is complex.). 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 |
|---|---|---|---|---|
| Testis | Pachytene spermatocytes | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Adrenal gland | Glandular cells | 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 → |
Section 3
Advanced SFRP1 IHC Tips
Troubleshoot SFRP1 staining in paraffin sections by checking retrieval, compartment, tissue context, and controls before comparing chromogenic signal across samples.
Which retrieval conditions should I try first for weak SFRP1 staining?
Start with heat-mediated retrieval in citrate buffer at pH 6 for 20 minutes (datasheet A01968-2). The selected paraffin-section example used those conditions before overnight incubation at 4°C with 1 μg/ml primary antibody (datasheet A01968-2). If staining remains weak, compare a longer heat exposure or an alternative buffer on adjacent sections while keeping antibody concentration and detection constant (standard IHC practice). Judge improvement by preserved tissue morphology and reproducible extracellular signal, since SFRP1 is secreted and may associate with extracellular matrix (UniProt Q8N474 localisation; HPA: extracellular positivity in several tissues).
Could fixation explain variable SFRP1 staining between paraffin blocks?
Target-specific sensitivity to fixation is unknown: the selected paraffin-section caption does not report its fixative (datasheet A01968-2). Record each block’s fixative and fixation duration, then compare sections processed with the same citrate pH 6, 20-minute retrieval and detection conditions (datasheet A01968-2; standard IHC practice). A consistent change between blocks supports a processing effect, but uneven staining within one section also warrants inspection for section damage and incomplete reagent coverage (standard IHC practice). Use a matched positive-control section in each run; the reported testis pachytene spermatocyte signal provides a tissue reference, without establishing a fixation optimum (HPA: High in pachytene spermatocytes).
Where should convincing SFRP1 staining appear in a paraffin section?
Look for extracellular or cell-associated staining rather than requiring a sharply membrane-confined pattern: SFRP1 is secreted, can associate with cell membrane or extracellular matrix, and has no transmembrane segment (UniProt Q8N474 localisation and topology). The tissue survey reports extracellular positivity in several tissues, so document both the stained compartment and its spatial relationship to nearby cells (HPA: tissue IHC profile; standard IHC practice). Compare those patterns with adjacent morphology and a negative reagent control under the same DAB development conditions (standard IHC practice). Cytoplasmic signal alone does not identify the producing cell, because secreted protein can be detected away from its source (UniProt Q8N474 localisation; HPA: reliability description).
How should epitope uncertainty affect my SFRP1 staining interpretation?
The supplied record lists 0 isoforms, a signal peptide at residues 1–31, and a secreted chain at 32–314 (UniProt Q8N474 processing and isoforms). It also lists an FZ domain at 53–169, an NTR domain at 186–306, and one glycosylation site at 173 (UniProt Q8N474 domains and glycosylation). Because the antibody’s epitope is unspecified here, these features do not establish which molecular form it recognizes in a section (supplied datasheet A01968-2 caption; UniProt Q8N474 processing). Compare staining after the documented citrate pH 6 retrieval with appropriate controls, and avoid assigning a change to glycosylation or cleavage without direct epitope evidence (datasheet A01968-2; standard IHC practice).
How can I evaluate SFRP1 alongside a cell marker by immunofluorescence?
Treat IF as a separate validation exercise; the supplied antibody example documents chromogenic paraffin-section IHC, while the supplied HPA subcellular record lists no ICC/IF images (datasheet A01968-2; HPA: subcellular record). Pair SFRP1 with a validated marker of the expected cell population, such as a pachytene spermatocyte marker when examining testis, and assess extracellular signal next to marked cells (HPA: High in pachytene spermatocytes; UniProt Q8N474 localisation). Choose a fluorophore channel with low tissue autofluorescence and include single-label controls to check bleed-through (standard IF practice). For an extracellular epitope, begin without permeabilisation; test permeabilisation separately if the epitope or an intracellular companion marker requires access, because this antibody’s epitope is unspecified (UniProt Q8N474 topology; standard IF practice).
What should I check when DAB obscures extracellular SFRP1 staining?
Inspect a section processed without primary antibody to identify detection-system or tissue background before changing the SFRP1 antibody concentration (standard IHC practice). The selected example used 10% goat serum blocking, 1 μg/ml primary antibody, a biotinylated secondary, streptavidin–biotin detection, and DAB (datasheet A01968-2). For diffuse DAB signal, check peroxidase blocking and consider background from the biotin-based detection system with matched reagent controls (standard chromogenic IHC practice; datasheet A01968-2). Shorten chromogen development or adjust blocking systematically while retaining a positive-control section, so loss of background is distinguishable from loss of extracellular SFRP1 signal (standard IHC practice; HPA: extracellular positivity in several tissues).
How should I score extracellular SFRP1 without overcounting positive cells? ⚠ ANSWER MARKED FOR VERIFICATION
Define the compartment to score before imaging: extracellular SFRP1 signal may extend beyond the cell that produced it (UniProt Q8N474 localisation; HPA: extracellular positivity in several tissues). For matrix-associated staining, measure positive stained area or optical-density signal per mm² of viable tissue; record the selected threshold and DAB development settings across sections (standard quantitative IHC practice). If cell-associated staining is the endpoint, report the percentage of positive cells or an H-score within a prespecified cell population (standard quantitative IHC practice). Normalise to viable tissue area or the number of eligible cells, respectively, and exclude folds, edges, and necrosis from the scoring region (standard quantitative IHC practice).
How do I distinguish true SFRP1 staining from an artefact?
Favour reproducible extracellular or cell-associated signal with intact morphology, consistent with SFRP1 secretion and the reported tissue IHC pattern (UniProt Q8N474 localisation; HPA: extracellular positivity in several tissues). A testis section can provide a contextual positive reference because pachytene spermatocytes were reported as High, but that result does not define every positive cell elsewhere (HPA: High in pachytene spermatocytes). Flag staining limited to section edges, folds, necrotic regions, or no-primary controls as potential artefact, and check peroxidase-related DAB signal with a detection control (standard chromogenic IHC practice). Interpret absent signal cautiously: HPA reports adipocytes as Not detected, while secreted protein location can differ from the location of its RNA (HPA: adipose tissue IHC and reliability description).
Boster reagents
Best SFRP1 / Secreted frizzled-related protein 1 IHC Antibodies
A01968-2 has IHC images from human colon and lung cancer and mouse intestine and kidney, plus an IF image from U20S cells (catalog image captions).
Real IHC data
Anti-SFRP1 Antibody ®
Cat # A01968-2
A01968-2 will render with a paraffin-section IHC figure; its captions also document IHC in human colon and lung cancer and mouse intestine and kidney, and IF in U20S cells (catalog image captions). M01968 will render with listed human reactivity and IHC, ICC and IF applications, but no IHC or IF image captions (catalog payload).
Which to pick: Choose A01968-2 for tissue IHC: its figure shows paraffin-section staining after citrate retrieval at pH 6, while the fixative is unreported (A01968-2 IHC caption). Choose A01968-2 for IF/ICC when an illustrated example matters; M01968 is a rabbit monoclonal with listed ICC/IF applications but no image caption (catalog payload). For work across species, A01968-2 lists human, mouse and rat reactivity, whereas M01968 lists human only; the IHC captions illustrate human and mouse tissue, with no rat example (catalog reactivity; A01968-2 IHC captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q8N474 (SFRP1_HUMAN, Secreted frizzled-related protein 1).
- Human Protein Atlas. SFRP1 tissue IHC expression (reliability: Approved).
- Human Protein Atlas. SFRP1 subcellular location (ICC-IF): Variation in transcript expression is not correlated to the cell cycle..
- Human Protein Atlas. SFRP1 antibody validation summary (1 antibodies).
- The Wnt antagonist sFRP1 is downregulated in premalignant large bowel adenomas. British journal of cancer 2006 — PMC2361362.
- Secreted Frizzled-Related Protein 1 as a Biomarker against Incomplete Age-Related Lobular Involution and Microcalcifications' Development. Cancers 2020 — PMC7565692.
- Diagnostic value of SFRP1 as a favorable predictive and prognostic biomarker in patients with prostate cancer. PloS one 2015 — PMC4342152.
- Deregulation of secreted frizzled-related proteins is associated with aberrant β-catenin activation in the carcinogenesis of oral submucous fibrosis. OncoTargets and therapy 2015 — PMC4610781.
- PubMed PMID:9192640 — UniProt-cited evidence.
- PubMed PMID:9391078 — UniProt-cited evidence.
- PubMed PMID:9724099 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for SFRP1 (Secreted frizzled-related protein 1). Expected localisation Extracellular tissue staining (HPA tissue IHC). Antigen retrieval: Citrate pH 6 HIER, heat-mediated (datasheet A01968-2). Validated IHC antibody: A01968-2 at 0.5-1μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Testis (Pachytene spermatocytes); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human colon cancer tissue; fixative not specified (datasheet A01968-2); 2. Fixation: Image fixative and duration unreported (datasheet A01968-2); 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: Citrate pH 6 , 20 min (datasheet A01968-2); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A01968-2); 8. Primary antibody: Rabbit anti-SFRP1, 0.5-1μg/ml (datasheet A01968-2); 9. Primary incubation: Overnight at 4 °C (datasheet A01968-2). Watch for: Fixation: Keep fixation conditions consistent across sections. (standard IHC practice; not target-specific); Caveat: Secreted SFRP1 may stain away from producing cells (UniProt); Isoform / epitope: No isoforms annotated; mature chain spans aa 32–314 (UniProt); Regulation: Tissue-dependent expression (UniProt). Evidence: UniProt Q8N474, HPA tissue IHC · Approved, HPA cell-line RNA · Variation in transcript expression is not correlated to the cell…, Datasheet A01968-2, PMC2361362, PMC7565692. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/SFRP1/immunohistochemistry-ihc-guide.