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FERMT2 / Fermitin family homolog 2 · IHC design guide
Design Immunohistochemistry for FERMT2
Plan FERMT2 chromogenic IHC on paraffin sections using the catalog antibody at 2–5 μg/ml (datasheet A03653-1). Expect mainly cytoplasmic staining, with high signal reported in glandular cells, while treating the tissue pattern as provisional (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
FERMT2 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 | Predominantly cytoplasmic in tissue (HPA tissue IHC) | |
| Staining pattern | Cytoplasmic in most tissues; high in glandular cells (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A03653-1) | |
| Positive control | Appendix+4 more · see all | |
| Negative control | Bone marrow+1 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 | Tissue staining awaits external verification (HPA tissue IHC) | |
| Regulation | Ubiquitous; no inducer specified (UniProt) | |
| Isoform / epitope | 3 isoforms; no TM span; epitope coverage unknown (UniProt) |
Section 1
Recommended FERMT2 IHC & IF Protocols
The catalog antibody protocol is accompanied by one published FERMT2 IHC protocol using human lung adenocarcinoma sections (PMC7923649).
| Sample | Paraffin-embedded human breast cancer tissue; fixative not specified (datasheet A03653-1) |
| Fixation | Image fixative and duration unreported (datasheet A03653-1); 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 A03653-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A03653-1) |
| Primary antibody | Rabbit anti-FERMT2, 2-5 μg/ml (datasheet A03653-1) |
| Primary incubation | Overnight at 4 °C (datasheet A03653-1) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet A03653-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | FERMT2-positive staining in glandular cells of appendix (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression in most tissues. No signal in the no-primary control. |
💡Decision noteStart with EDTA pH 8.0 heat retrieval (datasheet: A03653-1); the published microwave retrieval does not specify a buffer (PMC7923649).
Section 2
What Is the Expected FERMT2 Staining Pattern?
FERMT2 (Kindlin-2) is mainly cytoplasmic in tissue sections, with high HPA staining in glandular cells of the appendix, colon, duodenum and rectum; breast myoepithelial cells, pancreatic exocrine cells, skeletal myocytes and skin fibroblasts are also high (HPA tissue IHC). Its focal adhesion and cytoskeletal locations fit an intracellular pattern without a transmembrane segment (UniProt Q96AC1). HPA rates its tissue IHC profile Uncertain, pending external verification (HPA tissue IHC).
| Cytoplasmic chromogen appears in colon or rectal glandular cells, or in skeletal myocytes; cell outlines and tissue architecture remain readable (HPA tissue IHC). | This fits the reported high staining in those cell types and the predominantly cytoplasmic tissue profile (HPA tissue IHC). Judge the named cells, rather than treating every cell in a positive section as equally positive (HPA tissue IHC). |
| Stain is confined to gland lumens or extracellular material, with little signal in the adjacent cells. | A luminal or extracellular-only pattern does not match FERMT2’s reported cytoplasmic, cytoskeletal and focal adhesion locations or its lack of a transmembrane segment (UniProt Q96AC1; HPA tissue IHC). Review morphology and staining controls before calling it target signal (general IHC practice). |
| Bone marrow hematopoietic cells or ovarian stromal cells stain strongly despite the reported absence of staining in those cells (HPA tissue IHC). | Unexpected staining raises possible antibody cross-reactivity or endogenous detection activity (general IHC practice). The HPA negative calls are useful comparisons, but its overall tissue IHC reliability is Uncertain; one discrepant section does not establish the cause (HPA tissue IHC). |
| Broad, hazy chromogen covers cells and spaces, obscuring cell boundaries and the expected cytoplasmic pattern. | Treat this as background until controls show a cell-specific signal (general IHC practice). Check primary-antibody concentration, blocking, washes and detection controls; haze alone cannot establish FERMT2 localization (general IHC practice; HPA tissue IHC). |
| A well-preserved appendix or colon section lacks glandular-cell signal despite reported high staining in those cells (HPA tissue IHC). | First consider an assay failure or insufficient sensitivity, including the primary-antibody and detection steps (general IHC practice). Because HPA labels tissue IHC Uncertain, investigate with controls and another reported high-staining cell type before interpreting absence as biology (HPA tissue IHC). |
💡Expected FERMT2 appearanceCall a section positive when identifiable reported high-staining cells show predominantly cytoplasmic chromogen above controlled background—such as colon glandular cells or skeletal myocytes—while isolated luminal deposits or indiscriminate staining across unrelated cells warrant review (HPA tissue IHC; UniProt Q96AC1; general IHC practice).
| Tissue and cell choice (HPA tissue IHC) | HPA reports high staining in eight specified tissue–cell pairs, but low staining in caudate glia, parathyroid glandular cells and adipocytes (HPA tissue IHC). Score the reported cell population within each section; tissue names alone do not specify which cells should stain (HPA tissue IHC). |
| Compartment and topology (UniProt Q96AC1; HPA tissue IHC) | FERMT2 has cytoplasmic, cortical, cytoskeletal, focal adhesion and nuclear annotations and no transmembrane segment (UniProt Q96AC1). Predominantly cytoplasmic tissue staining is reported (HPA tissue IHC); a crisp continuous surface rim is therefore not required for a positive IHC call (UniProt Q96AC1; HPA tissue IHC). |
| Antibody evidence (HPA antibodies; HPA tissue IHC) | HPA040505 is Uncertain for IHC and Supported for ICC; HPA072965 has no listed IHC status and is Supported for ICC (HPA antibodies). The overall tissue IHC profile has medium antibody–RNA consistency and awaits external verification (HPA tissue IHC). |
| Isoforms and epitope information (UniProt Q96AC1) | UniProt lists 3 FERMT2 isoforms, but the supplied evidence does not locate an antibody epitope or establish isoform-specific staining (UniProt Q96AC1). Do not infer that staining differences identify a particular isoform (UniProt Q96AC1). |
| IF/ICC Q: What localization should I expect? (HPA subcellular) | A: HPA ICC-IF mainly supports focal adhesion sites, with additional supported nucleoplasm and cytosol localization (HPA subcellular). That finer pattern helps interpret cell images; it does not replace the reported cytoplasmic tissue IHC pattern or establish a paraffin-section IF protocol (HPA subcellular; HPA tissue IHC). |
| Situation | Likely cause | Next action |
|---|---|---|
| No stain in reported high-staining glandular cells (HPA tissue IHC). | The primary-antibody, detection or retrieval workflow may have failed; these are general assay possibilities, not demonstrated FERMT2-specific sensitivities (general IHC practice). | Review the catalog antibody’s IHC-P instructions, reagent preparation and run controls; compare with another reported high-staining tissue–cell pair (general IHC practice; HPA tissue IHC). |
| Signal appears only in lumens or extracellular deposits. | That distribution conflicts with the reported intracellular locations; precipitate or nonspecific staining is possible (UniProt Q96AC1; HPA tissue IHC; general IHC practice). | Inspect the unstained morphology and detection controls, then repeat with clean reagents and adequate washes if needed (general IHC practice). |
| Chromogen appears broadly, including in reported negative cell populations (HPA tissue IHC). | Endogenous detection activity or nonspecific antibody binding can mimic positive cells in chromogenic IHC (general IHC practice). | Check a no-primary control and the detection system’s endogenous-activity blocking step; interpret any remaining signal by cell type and compartment (general IHC practice; HPA tissue IHC). |
| The slide shows a strong nuclear-only pattern. | Nuclear localization is annotated, and nucleoplasm is supported in ICC-IF, but HPA describes tissue IHC as predominantly cytoplasmic (UniProt Q96AC1; HPA subcellular; HPA tissue IHC). | Do not automatically reject nuclear signal; verify cell identity, cytoplasmic signal and controls before treating nuclear-only IHC as a reproducible pattern (HPA tissue IHC; general IHC practice). |
| A reported low or unstained cell type is used to judge whether the run worked (HPA tissue IHC). | Low staining in caudate glia, parathyroid glandular cells or adipocytes, and no detected staining in marrow hematopoietic or ovarian stromal cells, offer little positive-control signal (HPA tissue IHC). | Include an HPA-reported high-staining cell type and assess that population directly; account for the Uncertain tissue IHC reliability when interpreting discrepancies (HPA tissue IHC). |
| Different sections show inconsistent intensity in the same reported cell type. | Section quality, staining-run variation or cell sampling can affect an IHC comparison (general IHC practice); HPA’s tissue IHC profile also awaits external verification (HPA tissue IHC). | Compare matched tissue areas with the same scoring criteria and run controls; document cell type, compartment and background before assigning a biological difference (general IHC practice; HPA tissue IHC). |
Experiment evidence
IHC & IF images showing FERMT2 staining
A03653-1 · IHCIHC analysis of Kindlin 2/FERMT2 using anti-Kindlin 2/FERMT2 antibody (A03653-1). Kindlin 2/FERMT2 was detected in a paraffin-embedded secti
A03653-1 · IHCIHC analysis of Kindlin 2/FERMT2 using anti-Kindlin 2/FERMT2 antibody (A03653-1). Kindlin 2/FERMT2 was detected in a paraffin-embedded secti
A03653-1 · IFIF analysis of Kindlin 2/FERMT2 using anti-Kindlin 2/FERMT2 antibody (A03653-1). Kindlin 2/FERMT2 was detected in an immunocytochemical sect
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000073712-FERMT2/tissue/cerebral+cortex#imid_10239229
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000073712-FERMT2/tissue/colon#imid_10239155
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000073712-FERMT2/tissue/liver#imid_10239148
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000073712-FERMT2/tissue/kidney#imid_10239149
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA040505; green = FERMT2, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA040505; green = FERMT2, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for FERMT2 IHC & IF
🧪Run breast first: myoepithelial cells should stain (HPA: High in breast myoepithelial cells). Use bone marrow hematopoietic cells as the negative tissue (HPA: Not detected); the supplied breast row identifies no internal target-negative cell population, so assess unstained areas for background without treating neighboring cells as a validated negative (HPA: breast myoepithelial-cell row; UniProt Q96AC1: ubiquitous).
Positive control tissue: Appendix (Glandular cells, HPA High)
Negative control tissue: Bone marrow (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show FERMT2 in A-431, U-251MG, U2OS, BJ [Human fibroblast], SiHa, with annotated localisation: Focal adhesion sites (supported) (HPA subcellular).
Technical controls: Include a no-primary (secondary-only) slide, a host-matched rabbit IgG isotype control, and FERMT2-knockout material processed alongside the test tissue (caption: rabbit primary antibody; standard IHC practice). Block endogenous peroxidase in breast sections before HRP/DAB detection (caption: breast section and HRP/DAB detection; standard IHC practice).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected A03653-1 tissue-IHC caption does not state the fixative (selected-SKU caption). The reported paraffin-section staining used heat-mediated EDTA retrieval at pH 8.0 and 2 μg/ml primary antibody; its success does not establish that retrieval is required under every condition (selected-SKU caption). The supplied evidence does not establish whether frozen sections or IF are easier; in breast sections, distinguish staining of the thin myoepithelial layer from adjacent cells when scoring (HPA: High in breast myoepithelial cells; HPA subcellular: focal adhesion sites supported).
HPA tissue IHC evidence for FERMT2
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Uncertain — Medium consistency between antibody staining and RNA expression data. Pending external verification.). 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 |
|---|---|---|---|---|
| Appendix | Glandular cells | High | Protein (IHC) | HPA → |
| Breast | Myoepithelial cells | High | Protein (IHC) | HPA → |
| Colon | Glandular cells | High | Protein (IHC) | HPA → |
| Duodenum | Glandular cells | High | Protein (IHC) | HPA → |
| Pancreas | Exocrine glandular cells | High | Protein (IHC) | HPA → |
Section 3
Advanced FERMT2 IHC Tips
Troubleshoot FERMT2 staining in paraffin sections by checking retrieval, compartment, cell identity, controls, and scoring against the available IHC evidence.
What retrieval conditions should I try when FERMT2 staining is weak?
Start with heat-mediated retrieval in EDTA at pH 8.0 for paraffin sections (datasheet A03653-1). The selected tissue image used 2 μg/ml primary antibody overnight at 4°C after this retrieval, so reproduce those conditions before changing the buffer (datasheet A03653-1). If staining remains weak, compare a citrate buffer at pH 6.0 on matched sections while keeping detection and exposure conditions constant (standard IHC practice). Include a positive-control tissue section and inspect morphology: excessive heating can damage tissue, whereas inadequate retrieval can leave the epitope inaccessible (standard IHC practice).
How should I assess whether fixation caused weak FERMT2 staining?
Target-specific sensitivity of FERMT2 staining to fixation is unknown from the supplied evidence; the selected caption identifies a paraffin section but does not state its fixative (datasheet A03653-1). Record fixative, fixation duration, section age, and retrieval conditions for each specimen, then compare sections processed under matched conditions (standard IHC practice). Use the documented EDTA retrieval at pH 8.0 and 2 μg/ml primary antibody as a reproducible starting point (datasheet A03653-1). If a specimen remains weak, assess a concurrently processed positive-control section before attributing the result to fixation, antigen abundance, or antibody performance (standard IHC practice).
Which staining compartments are plausible for FERMT2 in tissue?
Expect predominantly cytoplasmic staining across many tissues, while interpreting intensity within the relevant cell population (HPA tissue IHC: cytoplasmic expression in most tissues). FERMT2 also localizes to the cell cortex, actin-associated focal adhesions, and nucleus, so peripheral or nuclear signal can be biologically plausible when morphology supports it (UniProt Q96AC1 subcellular locations). Its focal-adhesion localization is supported in cell imaging, with additional nucleoplasmic and cytosolic localization (HPA subcellular). On paraffin sections, inspect cellular boundaries and counterstained nuclei at higher magnification; diffuse staining outside intact cells or confined to damaged section edges merits a technical check (standard IHC practice).
Could isoforms or epitope position explain discordant FERMT2 staining?
FERMT2 has 3 recorded isoforms, but the supplied tissue-IHC caption does not identify the antibody epitope or establish isoform coverage (UniProt Q96AC1 isoforms; datasheet A03653-1). Its FERM domain spans residues 189–661, its PH domain spans 380–476, and recorded phosphoserines include positions 159, 181, 339, 351, and 666 (UniProt Q96AC1 domains and modified residues). These annotations alone cannot establish whether retrieval or modification masks this antibody’s epitope (standard IHC interpretation). If results conflict, obtain the antibody’s immunogen or epitope information and compare independently validated antibodies on matched sections (standard IHC practice).
How can IF help resolve an ambiguous chromogenic FERMT2 pattern?
Use IF as a separate localization check alongside the paraffin-section IHC result; focal-adhesion, nucleoplasmic, and cytosolic locations are supported by cell imaging (HPA subcellular). Multiplex FERMT2 with a validated marker for the cell population being scored, and include single-label controls to assess channel bleed-through (standard IF practice). Choose fluorophores after checking tissue autofluorescence and select a channel with adequate separation from that background (standard IF practice). FERMT2 has no transmembrane segment and occupies intracellular sites, so permeabilize when testing an intracellular epitope; optimize that step for the IF specimen and antibody independently of the IHC caption (UniProt Q96AC1 topology and subcellular locations; standard IF practice).
What should I check when DAB staining is widespread?
The selected paraffin-section image used 10% goat serum blocking, a peroxidase-conjugated secondary antibody, and DAB development (datasheet A03653-1). Check a no-primary control and apply a peroxidase block to distinguish nonspecific detection or endogenous enzyme activity from primary-antibody-dependent staining (standard IHC practice). If background persists, review blocking, washes, primary concentration, and DAB development time on matched sections; the documented primary concentration is 2 μg/ml (datasheet A03653-1; standard IHC practice). Judge any remaining cytoplasmic signal against intact cell morphology and the broadly cytoplasmic tissue profile, rather than treating uniform color across tissue spaces as FERMT2 expression (HPA tissue IHC; standard IHC practice).
How should I score FERMT2 IHC across specimens? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and compartment before scoring, because tissue IHC shows broadly cytoplasmic expression while FERMT2 also has documented peripheral and nuclear locations (HPA tissue IHC; UniProt Q96AC1 subcellular locations). For chromogenic sections, record the percentage of positive intact cells and an intensity category, then calculate an H-score as the sum of each intensity category multiplied by its cell percentage (standard IHC practice). Normalize cell counts to the total eligible cells of the same type, or report positive-cell density per mm² of viable tissue when area is the denominator (standard IHC practice). Keep retrieval, staining batch, thresholds, and excluded regions consistent across specimens (standard IHC practice).
How do I distinguish true FERMT2 signal from staining artefact?
A convincing result follows intact cellular morphology and a plausible compartment: cytoplasmic tissue staining is common, and focal-adhesion or nuclear localization is documented (HPA tissue IHC; UniProt Q96AC1 subcellular locations). Check the identity of positive cells against the specimen; high staining is reported in breast myoepithelial cells and skin fibroblasts, while ovarian stromal cells are reported as not detected (HPA tissue IHC). Review edge-only staining, necrotic areas, and no-primary controls for processing artefact or endogenous peroxidase before calling cells positive (standard IHC practice). Treat agreement with HPA as supporting context, since its tissue-IHC reliability is marked uncertain and external verification is pending (HPA tissue IHC reliability).
Boster reagents
Best FERMT2 / Fermitin family homolog 2 IHC Antibodies
The catalog antibody has IHC data from human paraffin-embedded breast, colon, liver and renal cancer sections, plus IF data from U20S cells (catalog image captions).
Real IHC data
Anti-Kindlin 2/FERMT2 Antibody ®
Cat # A03653-1
A03653-1 is listed for human IHC and IF/ICC (catalog: applications and reactivity). Its IHC captions show paraffin-embedded human breast, colon, liver and renal cancer sections; its IF caption shows U20S cells (catalog image captions).
Which to pick: Choose A03653-1 for paraffin-section IHC: its IHC captions report heat retrieval in EDTA at pH 8.0, while the fixative is unreported (catalog IHC image captions). The same SKU is listed for IF/ICC and has a U20S cell IF image, making it the documented IF/ICC choice here (catalog: applications; IF image caption). Reactivity is listed only for human, so cross-species use is unsupported by this payload; clonality is unreported (catalog: reactivity and clone).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q96AC1 (FERM2_HUMAN, Fermitin family homolog 2).
- Human Protein Atlas. FERMT2 tissue IHC expression (reliability: Uncertain).
- Human Protein Atlas. FERMT2 subcellular location (ICC-IF): Mainly localized to the focal adhesion sites. In addition localized to the nucleoplasm and cytosol..
- Human Protein Atlas. FERMT2 antibody validation summary (2 antibodies).
- Overexpression of FERM Domain Containing Kindlin 2 (FERMT2) in Fibroblasts Correlates with EMT and Immunosuppression in Gastric Cancer. International journal of genomics 2024 — PMC10864055.
- Construction of the optimization prognostic model based on differentially expressed immune genes of lung adenocarcinoma. BMC cancer 2021 — PMC7923649.
- TGF-βI/FERMT2/COL6A1 Reciprocal Loop Drives Tumor-Stroma Crosstalk and Promotes Peritoneal Metastasis in Gastric Cancer. International journal of biological sciences 2025 — PMC12509910.
- The role of FERMT2 in the tumor microenvironment and immunotherapy in pan-cancer using comprehensive single-cell and bulk sequencing. Heliyon 2024 — PMC11079299.
- PubMed PMID:8175911 — UniProt-cited evidence.
- PubMed PMID:12697302 — UniProt-cited evidence.
- PubMed PMID:12679033 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for FERMT2 (Fermitin family homolog 2). Expected localisation Predominantly cytoplasmic in tissue (HPA tissue IHC). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A03653-1). Validated IHC antibody: A03653-1 at 2-5 μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Appendix (Glandular cells); negative Bone marrow. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human breast cancer tissue; fixative not specified (datasheet A03653-1); 2. Fixation: Image fixative and duration unreported (datasheet A03653-1); 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 A03653-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A03653-1); 8. Primary antibody: Rabbit anti-FERMT2, 2-5 μg/ml (datasheet A03653-1); 9. Primary incubation: Overnight at 4 °C (datasheet A03653-1). Watch for: Fixation: Keep fixation consistent across sections (standard IHC practice; not target-specific); Caveat: Tissue staining awaits external verification (HPA tissue IHC); Isoform / epitope: 3 isoforms; no TM span; epitope coverage unknown (UniProt); Regulation: Ubiquitous; no inducer specified (UniProt). Evidence: UniProt Q96AC1, HPA tissue IHC · Uncertain, HPA ICC-IF · Mainly localized to the focal adhesion sites. In addition localized…, Datasheet A03653-1, PMC7923649. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/FERMT2/immunohistochemistry-ihc-guide.