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FHL1 / Four and a half LIM domains protein 1 · IHC design guide
Design Immunohistochemistry for FHL1
Plan FHL1 paraffin IHC using skeletal myocytes and thyroid glandular cells as high staining references (HPA tissue IHC). Start the IHC-validated antibody at 0.5–1 µg/ml (datasheet A01258-1) and compare cellular staining with controls.
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
FHL1 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 or nuclear potential; tissue compartment unconfirmed (UniProt) | |
| Staining pattern | High staining in skeletal myocytes and thyroid glandular cells (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A01258-1) | |
| Positive control | Endometrium+4 more · see all | |
| Negative control | Adrenal gland+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 A01258-1) | |
| Caveat | Differentiation can shift FHL1 from nucleus to cytosol (UniProt) | |
| Regulation | Isoform 1 is enriched in skeletal muscle (UniProt) | |
| Isoform / epitope | Five isoforms; check antibody epitope coverage across them (UniProt) |
Section 1
Recommended FHL1 IHC & IF Protocols
The catalog antibody’s IHC-P protocol (datasheet A01258-1) is accompanied by three published FHL1 IHC protocols (PMC7202308; PMC11551809; PMC6687666).
| Sample | Paraffin-embedded human rectal cancer tissue; fixative not specified (datasheet A01258-1) |
| Fixation | Image fixative and duration unreported (datasheet A01258-1); 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 A01258-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A01258-1) |
| Primary antibody | Rabbit anti-FHL1, 0.5-1μg/ml (datasheet A01258-1) |
| Primary incubation | Overnight at 4 °C (datasheet A01258-1) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet A01258-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | FHL1-positive staining in smooth muscle cells of endometrium (HPA tissue IHC: High). HPA tissue profile: Distinct expression in muscle tissue and thyroid glands. No signal in the no-primary control. |
💡Decision noteStart with EDTA pH 8.0 heat retrieval (datasheet A01258-1). If staining is weak, compare citrate pH 6.0 pressure-cooker retrieval (PMC7202308).
Section 2
What Is the Expected FHL1 Staining Pattern?
FHL1 should stain mainly cytoplasmic structures, with nuclear signal possible in myoblasts; differentiated myotubes are described as cytosolic (UniProt Q13642 localisation). In tissue IHC, strong signal is reported in skeletal myocytes, smooth muscle cells and thyroid glandular cells (HPA tissue IHC: High). FHL1 has no transmembrane segment (UniProt Q13642 topology). HPA rates its tissue IHC evidence Enhanced, with medium consistency between antibody staining and RNA expression (HPA tissue IHC reliability).
| Strong chromogenic staining in skeletal myocytes, with identifiable cell boundaries and a clean surrounding field. | This matches a high-signal reference cell type (HPA tissue IHC: skeletal myocytes High). Assess the stained cells and their compartment, not the apparent intensity of the whole section; FHL1 is reported in cytoplasm and nucleus, with a cytosolic pattern in differentiated myotubes (UniProt Q13642 localisation). |
| Signal appears exclusively in an unexpected compartment, with no convincing cytoplasmic staining in positive cells. | Treat this as a pattern that needs checking, rather than immediate evidence of FHL1: cytoplasmic and nuclear localisation are reported by UniProt (UniProt Q13642 localisation). A membrane component has been observed in ICC-IF, so membrane signal alone cannot be dismissed categorically; that observation does not establish an expected paraffin IHC pattern (HPA subcellular: plasma membrane Supported). |
| Strong colour appears in cells listed as unstained, or across many unrelated cell types. | Check specificity and detection background before scoring it as FHL1 (standard IHC practice). For example, adrenal glandular cells and bronchial respiratory epithelial cells are listed as Not detected (HPA tissue IHC). Interpret at cell-type level: lung alveolar type I cells are High even though bronchial respiratory epithelial cells are Not detected (HPA tissue IHC). |
| Weak, diffuse colour covers both cells and spaces between them, obscuring cell outlines. | This is difficult to score as a cellular FHL1 pattern (standard IHC practice). Compare with a primary-antibody omission control and inspect blocking, washes and chromogen development for nonspecific background (standard IHC practice). HPA's Enhanced tissue rating describes its antibody evidence; it does not validate background in this run (HPA tissue IHC reliability). |
| No detectable signal in skeletal myocytes while the counterstain and tissue morphology remain readable. | Skeletal myocytes are a useful positive reference because HPA reports High staining there (HPA tissue IHC). Review antibody application, detection reagents and the run's positive control before calling the specimen negative (standard IHC practice). The supplied sources do not establish a target-specific fixation sensitivity or an FHL1 antigen-retrieval condition. |
💡Expected FHL1 appearanceA persuasive positive is strong, cell-resolved staining in skeletal myocytes or another HPA High cell type, with cytoplasmic localisation consistent with UniProt; widespread diffuse colour or strong signal in HPA Not detected cells warrants a specificity check (HPA tissue IHC: High/Not detected; UniProt Q13642 localisation; standard IHC practice).
| Cell type and sampling | Choose and score the relevant cells within each section: skeletal myocytes, thyroid glandular cells and endometrial smooth muscle cells are High, whereas several other sampled cell types are Not detected (HPA tissue IHC). A mixed tissue can therefore contain both expected positive and expected unstained cells (HPA tissue IHC). |
| Isoform distribution | Five isoforms are listed, and their reported tissue distributions differ (UniProt Q13642 isoforms and tissue specificity). An antibody's recognised epitope is not supplied here, so a tissue result cannot be assigned to a particular isoform from this record alone. |
| Subcellular interpretation | UniProt places FHL1 in cytoplasm and nucleus and describes a myoblast-to-myotube localisation difference (UniProt Q13642 localisation). HPA ICC-IF calls cytosol uncertain and additional plasma membrane localisation supported (HPA subcellular); use that as context, not as a required chromogenic IHC pattern. |
| Strength of the tissue reference | HPA assigns tissue IHC Enhanced reliability while reporting medium consistency with RNA expression (HPA tissue IHC reliability). Its three listed antibodies each have Enhanced IHC validation (HPA antibodies); that supports use of the reported pattern as a reference but does not validate the catalog antibody or every tissue preparation. |
| Detection method | If using enzyme-based chromogenic detection, endogenous enzyme activity and nonspecific reagent binding can create colour unrelated to primary-antibody binding (standard IHC practice). Use method-appropriate controls to separate those signals; this is general workflow advice, not a reported FHL1-specific effect. |
| Situation | Likely cause | Next action |
|---|---|---|
| Skeletal muscle positive control is blank. | A failed antibody or detection step is possible (standard IHC practice); skeletal myocytes are expected to stain strongly (HPA tissue IHC: High). | Check that the primary antibody, detection reagents and chromogen were applied and active; rerun with an appropriate positive control (standard IHC practice). Review antigen retrieval against the antibody's own IHC instructions without assuming an FHL1-specific retrieval requirement. |
| The entire section is brown, including spaces without cells. | Nonspecific reagent deposition, inadequate washing or excessive chromogen development may obscure cellular staining (standard IHC practice). | Compare a primary-antibody omission control; review blocking, washing and development time for the detection system (standard IHC practice). Score FHL1 only after cell boundaries and compartments can be distinguished. |
| Strong signal appears in adrenal glandular cells or bronchial respiratory epithelial cells. | Those specific cell types are listed as Not detected (HPA tissue IHC); cross-reactivity or detection background is possible (standard IHC practice). | Check the exact stained cell population, then compare omission and other appropriate specificity controls (standard IHC practice). Do not generalise a negative bronchial epithelial result to lung alveolar type I cells, which are High (HPA tissue IHC). |
| Staining is mainly nuclear in a section expected to contain differentiated muscle cells. | UniProt describes predominantly nuclear FHL1 in myoblasts and cytosolic FHL1 in differentiated myotubes (UniProt Q13642 localisation). The supplied evidence does not define a nuclear-only paraffin IHC reference pattern. | Confirm cell identity and morphology, inspect the positive control and compare the distribution with background controls before interpreting a nuclear-only result (standard IHC practice). |
| Signal varies between apparently similar fields or tissues. | The sampled cell types may differ: HPA reports High skeletal myocytes and thyroid glandular cells but Medium adipocytes and Low ovarian stroma cells (HPA tissue IHC). HPA also reports only medium consistency with RNA expression (HPA tissue IHC reliability). | Record the cell type and compartment for each scored area, and compare like cells across sections under the same staining conditions (standard IHC practice). Avoid treating a tissue-level average as a required intensity for every cell. |
| Can an IF/ICC image determine the expected paraffin IHC pattern? | HPA's ICC-IF summary reports mainly cytosolic localisation with additional plasma membrane signal, while marking the cytosol assignment uncertain (HPA subcellular). Its images come from A-431, U-251MG and U2OS cells (HPA subcellular). | Use those images only as localisation context. Judge chromogenic tissue staining against HPA's cell-specific IHC observations and the section's controls (HPA tissue IHC; standard IHC practice). |
Experiment evidence
IHC & IF images showing FHL1 staining
A01258-1 · IHCIHC analysis of FHL using anti-FHL antibody (A01258-1). FHL was detected in paraffin-embedded section of human rectal cancer tissue. Heat me
A01258-1 · IHCIHC analysis of FHL using anti-FHL antibody (A01258-1). FHL was detected in paraffin-embedded section of human renal cancer tissue. Heat med
A01258-1 · IFIF analysis of FHL using anti-FHL antibody (A01258-1). FHL was detected in immunocytochemical section of U20S cells. Enzyme antigen retrieva
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000022267-FHL1/tissue/cerebral+cortex#imid_5421196
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000022267-FHL1/tissue/colon#imid_5421106
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000022267-FHL1/tissue/liver#imid_5421107
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000022267-FHL1/tissue/kidney#imid_5421116
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA001040; green = FHL1, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA001040; green = FHL1, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for FHL1 IHC & IF
🧪Run skeletal muscle first: myocytes should stain strongly (HPA: High in skeletal muscle myocytes; UniProt Q13642: isoform 1 is highly expressed in skeletal muscle). Use adrenal gland glandular cells as the negative tissue (HPA: Not detected); on the positive slide, assess nonmyocyte cells for background staining, but do not assume every nonmyocyte is FHL1-negative.
Positive control tissue: Endometrium (Smooth muscle cells, HPA High)
Negative control tissue: Adrenal gland (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show FHL1 in A-431, U-251MG, U2OS, with annotated localisation: Cytosol (uncertain) (HPA subcellular).
Technical controls: Include a no-primary secondary-only control, a concentration-matched rabbit IgG isotype control, and FHL1 knockout tissue or cells as a biological negative (selected A01258-1 caption: rabbit primary antibody). For chromogenic detection, quench endogenous peroxidase and check for endogenous biotin signal because the reported detection uses a biotinylated secondary and streptavidin–biotin complex (selected A01258-1 caption).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the exact A01258-1 tissue-IHC caption does not state the fixative. That caption reports heat retrieval in EDTA pH 8.0, but does not establish that retrieval is required or that frozen sections or IF are easier. Skeletal muscle myocytes are an HPA High positive, so assess background in adjacent nonmyocyte areas before scoring (HPA: High in skeletal muscle myocytes).
HPA tissue IHC evidence for FHL1
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — 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 |
|---|---|---|---|---|
| Endometrium | Smooth muscle cells | High | Protein (IHC) | HPA → |
| Lung | Alveolar cells type I | High | Protein (IHC) | HPA → |
| Placenta | Syncytiotrophoblasts - cell body | High | Protein (IHC) | HPA → |
| Skeletal muscle | Myocytes | High | Protein (IHC) | HPA → |
| Testis | Elongated or late spermatids | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adrenal gland | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Appendix | Endocrine cells | Not detected | Protein (IHC) | HPA → |
| Bone marrow | Hematopoietic cells | Not detected | Protein (IHC) | HPA → |
| Bronchus | Respiratory epithelial cells | Not detected | Protein (IHC) | HPA → |
| Caudate | Glial cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced FHL1 IHC Tips
Troubleshoot FHL1 staining in paraffin sections using the catalog antibody’s tissue IHC caption and protein localisation evidence (datasheet A01258-1; UniProt Q13642).
Which retrieval condition should I try first when FHL1 staining is weak in paraffin sections?
Start with heat mediated retrieval in EDTA pH 8.0 for paraffin sections (datasheet A01258-1). Compare a known positive control, such as skeletal muscle myocytes, across runs before changing retrieval conditions (HPA: High in skeletal muscle myocytes; standard IHC practice). Keep section thickness, heating, cooling and antibody incubation consistent so a change in signal can be attributed to retrieval (standard IHC practice). If staining remains weak, test an alternative retrieval buffer on adjacent control sections and record tissue preservation alongside signal (standard IHC practice). The caption documents EDTA retrieval for this SKU, but gives no heating duration or fixative (datasheet A01258-1).
How should I investigate a suspected fixation problem with FHL1 IHC?
FHL1 specific sensitivity to fixation is unknown from the supplied evidence; the paraffin section caption does not state its fixative (datasheet A01258-1). Record the actual fixative and fixation duration for each specimen, then compare similarly processed sections with a known positive tissue control (standard IHC practice; HPA: High in skeletal muscle myocytes). Keep retrieval at EDTA pH 8.0 while evaluating the effect of processing differences (datasheet A01258-1; standard IHC practice). Check section integrity and counterstain before interpreting weak chromogen as loss of antigen (standard IHC practice). Do not infer fixation sensitivity from FHL1 localisation, modifications or tissue expression patterns (UniProt Q13642; HPA tissue IHC).
Should FHL1 staining appear in nuclei, cytoplasm, or at the cell surface?
Assess nuclear and cytoplasmic staining separately because FHL1 has both reported locations (UniProt Q13642). UniProt describes predominantly nuclear localisation in myoblasts and cytosolic localisation in differentiated myotubes, so cell state matters when interpreting a section (UniProt Q13642). HPA reports mainly cytosolic staining and an additional plasma membrane location in cell imaging, with uncertainty attached to its main cytosolic assignment (HPA subcellular). FHL1 has no transmembrane segment, so a sharp surface outline alone should prompt a specificity check against neighbouring cells and controls (UniProt Q13642 topology; standard IHC practice). Compare compartments within identified cells rather than pooling all DAB signal into one score (standard IHC practice).
Could an antibody epitope explain different FHL1 patterns across tissues?
Check the catalog antibody’s documented immunogen or epitope before assigning a staining difference to an FHL1 isoform (standard IHC practice). FHL1 has 5 listed isoforms, and isoform expression differs among tissues (UniProt Q13642). Isoform 1 is highly expressed in skeletal muscle, while isoform 3 is reported in testis, heart and skeletal muscle (UniProt Q13642). Three annotated LIM zinc binding regions span residues 40–92, 101–153 and 162–212, making epitope mapping relevant when comparing antibody reactivity (UniProt Q13642). Because the supplied caption does not identify the antibody epitope, tissue staining alone cannot establish isoform selectivity (datasheet A01258-1; standard IHC practice).
How can I check FHL1 localisation by multiplex IF alongside this IHC guide?
Use a separate IF validation workflow, since the supplied catalog evidence documents paraffin section chromogenic IHC rather than IF conditions (datasheet A01258-1). Pair FHL1 with a marker identifying the expected cell type, such as a validated myocyte marker in skeletal muscle, and include single stain controls (HPA: High in skeletal muscle myocytes; standard IF practice). Select fluorophores after checking tissue autofluorescence and bleed through, particularly when comparing weak cytosolic signal with a brighter cell marker (standard IF practice; HPA subcellular). Permeabilise appropriately for the intracellular epitope and verify antibody access with controls; FHL1 has no transmembrane segment and is reported in nucleus and cytoplasm (UniProt Q13642 topology and localisation; standard IF practice).
What should I adjust if DAB obscures FHL1 positive cells?
Compare no primary controls and known positive sections before changing the primary antibody concentration (standard IHC practice; HPA: High in skeletal muscle myocytes). The catalog image used 10% goat serum blocking, 1 µg/ml primary antibody overnight at 4°C, and a biotinylated secondary for 30 minutes at 37°C (datasheet A01258-1). Its streptavidin biotin complex with DAB makes endogenous biotin and peroxidase activity potential sources of misleading colour (datasheet A01258-1; standard IHC practice). Check the peroxidase block, washes and secondary only control as general chromogenic workflow checks (standard IHC practice). Judge improvement by clearer cell boundaries and retained positive control signal, rather than by a paler slide alone (standard IHC practice).
How should I quantify FHL1 DAB staining across tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and compartment before scoring, because FHL1 staining may be cytoplasmic or nuclear (UniProt Q13642 localisation; standard IHC practice). For an intensity based comparison, report an H score from the percentage of cells at each staining intensity; alternatively, report percentage positive cells or positive cell density per mm² (standard IHC practice). Normalise cell counts to the number of evaluable cells in the same annotated compartment, or normalise density to evaluable tissue area (standard IHC practice). Apply one staining threshold and identical image settings across samples, with positive and no primary controls reviewed alongside them (standard IHC practice). Report nuclear and cytoplasmic scores separately when both occur (UniProt Q13642 localisation; standard IHC practice).
How do I distinguish genuine FHL1 positivity from staining artefacts?
Look for reproducible staining within identifiable cells and compare its compartment with FHL1’s reported nuclear and cytoplasmic locations (UniProt Q13642 localisation; standard IHC practice). Skeletal muscle myocytes provide a documented high staining reference, while HPA also reports high staining in thyroid glandular cells; tissue identity should guide comparison (HPA tissue IHC). Treat staining confined to section edges, necrotic regions or damaged areas cautiously, and inspect a no primary control for nonspecific DAB colour (standard IHC practice). Check endogenous peroxidase activity when colour persists without primary antibody, especially in this DAB workflow (datasheet A01258-1; standard IHC practice). A convincing result combines the expected cell population, plausible compartment and clean controls (UniProt Q13642 localisation; HPA tissue IHC; standard IHC practice).
Boster reagents
Best FHL1 / Four and a half LIM domains protein 1 IHC Antibodies
The catalog covers human paraffin-section IHC and IF in U20S cells (A01258-1 image captions); a second IHC-listed antibody has human, mouse and rat reactivity (M01258 catalog).
Real IHC data
Anti-FHL FHL1 Antibody ®
Cat # A01258-1
A01258-1 has IHC images from human rectal and renal cancer paraffin sections and an IF image from U20S cells (A01258-1 image captions). M01258 is listed for IHC with human, mouse and rat reactivity, but has no IHC image in the payload (M01258 catalog).
Which to pick: For tissue IHC, choose A01258-1 when a demonstrated human paraffin-section workflow is useful; its captions specify EDTA retrieval at pH 8.0 and 1 μg/ml primary antibody, while the fixative is unreported (A01258-1 IHC captions). For IF/ICC, choose A01258-1 because both applications are listed and its U20S cell IF image uses 2 μg/ml primary antibody (A01258-1 catalog and IF caption). For mouse or rat work, consider rabbit monoclonal M01258 because those species and IHC are listed, while its payload provides no tissue IHC image or fixation details (M01258 catalog).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry Q13642 (FHL1_HUMAN, Four and a half LIM domains protein 1).
- Human Protein Atlas. FHL1 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. FHL1 subcellular location (ICC-IF): Mainly localized to the cytosol. In addition localized to the plasma membrane..
- Human Protein Atlas. FHL1 antibody validation summary (3 antibodies).
- Downregulation of FHL1 protein in glioma inhibits tumor growth through PI3K/AKT signaling. Oncology letters 2020 — PMC7202308.
- FHL1: A novel diagnostic marker for papillary thyroid carcinoma. Pathology international 2024 — PMC11551809.
- Transcriptional Analysis Reveals That the FHL1/JAK-STAT Pathway is Involved in Acute Cartilage Injury in Mice. Cartilage 2025 — PMC11948231.
- Molecular autopsy and family screening in a young case of sudden cardiac death reveals an unusually severe case of FHL1 related hypertrophic cardiomyopathy. Molecular genetics & genomic medicine 2019 — PMC6687666.
- PubMed PMID:8753811 — UniProt-cited evidence.
- PubMed PMID:9714789 — UniProt-cited evidence.
- PubMed PMID:10352231 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for FHL1 (Four and a half LIM domains protein 1). Expected localisation Cytoplasmic or nuclear potential; tissue compartment unconfirmed (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A01258-1). Validated IHC antibody: A01258-1 at 0.5-1μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Endometrium (Smooth muscle cells); negative Adrenal gland. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human rectal cancer tissue; fixative not specified (datasheet A01258-1); 2. Fixation: Image fixative and duration unreported (datasheet A01258-1); 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 A01258-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A01258-1); 8. Primary antibody: Rabbit anti-FHL1, 0.5-1μg/ml (datasheet A01258-1); 9. Primary incubation: Overnight at 4 °C (datasheet A01258-1). Watch for: Fixation: Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image A01258-1); Caveat: Differentiation can shift FHL1 from nucleus to cytosol (UniProt); Isoform / epitope: Five isoforms; check antibody epitope coverage across them (UniProt); Regulation: Isoform 1 is enriched in skeletal muscle (UniProt). Evidence: UniProt Q13642, HPA tissue IHC · Enhanced, HPA ICC-IF · Mainly localized to the cytosol. In addition localized to the plasma…, Datasheet A01258-1, PMC7202308, PMC11551809. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/FHL1/immunohistochemistry-ihc-guide.