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LTA4H / Leukotriene A-4 hydrolase · IHC design guide
Design Immunohistochemistry for LTA4H
This guide maps LTA4H nuclear and cytoplasmic tissue staining and highlights strongly stained lung macrophages (HPA tissue IHC). It gives a paraffin-section IHC starting concentration of 1–2 μg/mL and covers fixation, detection, and scoring (datasheet A02399-1; standard IHC practice).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
LTA4H 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 | Nuclear and cytoplasmic staining in most tissues (HPA tissue IHC) | |
| Staining pattern | Cells in most tissues show nuclear and cytoplasmic staining (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A02399-1) | |
| Positive control | Adrenal gland+4 more · see all | |
| Negative control | None in HPA (detected in all 45 tissues); use no-primary + isotype controls |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep fixation consistent across sections (standard IHC practice; not target-specific) | |
| Caveat | Strong lung macrophage staining may complicate scoring (HPA tissue IHC) | |
| Regulation | No specific expression regulator reported (UniProt) | |
| Isoform / epitope | 4 isoforms; antibody epitope coverage is unknown (UniProt) |
Section 1
Recommended LTA4H IHC & IF Protocols
The catalog antibody’s IHC-P protocol uses EDTA pH 8.0 retrieval (datasheet: A02399-1). Three published LTA4H IHC protocols provide additional conditions (PMC8710725; PMC3917894; PMC11731977).
| Sample | Paraffin-embedded human esophageal squamous carcinoma tissue; fixative not specified (datasheet A02399-1) |
| Fixation | Image fixative and duration unreported (datasheet A02399-1); 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 A02399-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A02399-1) |
| Primary antibody | Rabbit anti-LTA4H, 1-2 μg/ml (datasheet A02399-1) |
| Primary incubation | Overnight at 4 °C (datasheet A02399-1) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet A02399-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | LTA4H-positive staining in glandular cells of adrenal gland (HPA tissue IHC: High). HPA tissue profile: Nuclear and cytoplasmic expression in most tissues. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA pH 8.0 for the catalog antibody (datasheet: A02399-1); published protocols used different retrieval buffers with their own antibodies (PMC8710725; PMC3917894; PMC11731977).
Section 2
What Is the Expected LTA4H Staining Pattern?
LTA4H is a cytoplasmic protein with no transmembrane segment (UniProt P09960: subcellular location and topology). In IHC, expect staining in many tissues, with nuclear and cytoplasmic expression reported across most tissues (HPA tissue IHC: Supported; medium consistency with RNA data). Lung macrophages, bone marrow hematopoietic cells, and several epithelial or glandular cell populations are reported as high (HPA tissue IHC: High).
| Cytoplasmic staining in lung macrophages or bone marrow hematopoietic cells, with some nuclear staining. | This fits the reported high staining in those cells and the nuclear and cytoplasmic tissue profile (HPA tissue IHC: High; tissue profile). Judge the nuclear component in the context of the cytoplasmic signal: ICC-IF supports cytosol as the main location, while nucleoplasm is listed as uncertain (HPA subcellular: supported cytosol; uncertain nucleoplasm). |
| Staining is restricted to cell membranes or extracellular material, with little cellular staining. | Treat a dominant membrane or extracellular pattern as suspect: UniProt places LTA4H in the cytoplasm and reports no transmembrane segment or signal peptide (UniProt P09960: location, topology, processing). Compare its distribution with a high-staining cell population and check a negative detection control before attributing it to LTA4H (HPA tissue IHC: High; standard IHC practice). |
| Strong staining appears chiefly in an unexpected cell population or tissue compartment. | HPA reports low tissue specificity, so an unlisted cell type alone does not establish a false positive (HPA tissue IHC: RNA specificity). A pattern that spares the expected high-staining cells and instead tracks unrelated structures warrants checks for antibody cross-reactivity or endogenous detection activity (HPA tissue IHC: High; standard IHC practice). |
| Diffuse chromogen covers cells and surrounding tissue, obscuring intracellular boundaries. | This cannot be scored confidently as LTA4H localisation; diffuse background may reflect nonspecific binding or detection background (standard IHC practice). Compare a matched negative detection control and assess whether recognizable cytoplasmic staining persists in the expected cells (standard IHC practice; HPA tissue IHC: High). |
| No detectable staining appears in lung macrophages or bone marrow hematopoietic cells. | These are reported high-staining populations, so an absent signal calls for a technical review before interpreting the sample as LTA4H negative (HPA tissue IHC: High; standard IHC practice). Check that the selected antibody has IHC support, then review the staining and detection controls (HPA antibodies: IHC Supported; standard IHC practice). |
💡Expected LTA4H appearanceCall a result positive when identifiable cells show cytoplasmic staining, potentially with nuclear staining, especially in populations reported high such as lung macrophages or bone marrow hematopoietic cells; dominant membrane staining or diffuse extracellular colour is suspect (HPA tissue IHC: profile and High; UniProt P09960: cytoplasm and topology).
| Cell population and tissue choice | HPA reports high staining in lung macrophages, bone marrow hematopoietic cells, esophageal squamous epithelial cells, and several glandular populations (HPA tissue IHC: High). It reports low staining in cardiomyocytes and skeletal myocytes; low is a comparison level, not proof of absence (HPA tissue IHC: Low). |
| Compartment evidence | UniProt assigns LTA4H to the cytoplasm (UniProt P09960: subcellular location). HPA tissue IHC describes nuclear and cytoplasmic expression, whereas ICC-IF supports cytosol and labels additional nucleoplasm uncertain; interpret a nuclear-only result cautiously (HPA tissue IHC: profile; HPA subcellular: supported cytosol, uncertain nucleoplasm). |
| Antibody validation | Three listed antibodies have IHC Supported status: HPA008399, HPA017017, and CAB015221 (HPA antibodies: IHC Supported). The tissue profile has Supported reliability with medium consistency against RNA data; those labels support comparison with the reported pattern without guaranteeing every specimen will match (HPA tissue IHC: reliability). |
| Isoforms and protein organisation | UniProt lists four isoforms and reports isoforms 1 and 2 in monocytes, lymphocytes, neutrophils, reticulocytes, platelets, and fibroblasts (UniProt P09960: isoforms and tissue specificity). The supplied antibody records give no epitope or isoform coverage, so a difference between antibodies cannot be assigned to an isoform from this evidence (HPA antibodies: supplied validation records). |
| IF/ICC Q: Should the same compartment pattern appear in cells? | A: Cytosol is the supported main ICC-IF location; nucleoplasm is an additional uncertain location (HPA subcellular). HPA008399 has ICC Supported status, but the IHC tissue pattern alone does not establish an ICC-IF result for the other listed antibodies (HPA antibodies: ICC status). |
| Situation | Likely cause | Next action |
|---|---|---|
| A reported high-staining population is blank. | The staining or detection workflow may have failed; a blank slide alone cannot distinguish that from a sample-specific result (standard IHC practice; HPA tissue IHC: High). | Run a known-positive tissue alongside the sample, confirm the antibody's IHC support, and inspect the detection controls before scoring absence (HPA tissue IHC: High; HPA antibodies: IHC Supported; standard IHC practice). |
| Nuclear signal dominates while cytoplasm is faint or absent. | HPA reports nuclear staining in tissue, but ICC-IF lists nucleoplasm as uncertain and cytosol as supported (HPA tissue IHC: profile; HPA subcellular: locations). | Check whether expected cells also have cytoplasmic signal, then compare a negative detection control; avoid treating isolated nuclear staining as decisive (HPA tissue IHC: High; HPA subcellular: supported cytosol; standard IHC practice). |
| Cell borders or extracellular deposits dominate the image. | That distribution conflicts with the cytoplasmic assignment and lack of a transmembrane segment or signal peptide (UniProt P09960: location, topology, processing). | Inspect a negative detection control and compare the pattern with intracellular staining in a reported high-staining population (standard IHC practice; HPA tissue IHC: High). |
| Staining is widespread and weak, making cell types hard to distinguish. | HPA reports broad tissue expression, while diffuse detection background can also obscure cell boundaries (HPA tissue IHC: profile and low RNA tissue specificity; standard IHC practice). | Compare matched negative controls and score signal only where cellular boundaries and compartment are clear (standard IHC practice). |
| Strong staining appears outside the expected high-staining cells. | Low tissue specificity leaves room for additional positive cells; cross-reactivity or endogenous detection activity is also possible (HPA tissue IHC: RNA specificity; standard IHC practice). | Check whether expected high-staining cells are positive, and use negative detection controls to assess background before assigning specificity (HPA tissue IHC: High; standard IHC practice). |
| Two antibodies give different tissue patterns. | All three listed antibodies have IHC Supported status, but the supplied validation records do not state their epitopes or isoform coverage (HPA antibodies: IHC status and supplied records). | Compare each pattern with HPA's cell-level observations and its medium-consistency reliability assessment; do not infer an isoform-specific cause from these records (HPA tissue IHC: profile and reliability; UniProt P09960: four isoforms). |
Experiment evidence
IHC & IF images showing LTA4H staining
A02399-1 · IHCIHC analysis of LTA4H using anti-LTA4H antibody (A02399-1). LTA4H was detected in a paraffin-embedded section of human esophageal squamous c
A02399-1 · IHCIHC analysis of LTA4H using anti-LTA4H antibody (A02399-1). LTA4H was detected in a paraffin-embedded section of human liver cancer tissue.
A02399-1 · IFIF analysis of LTA4H using anti-LTA4H antibody (A02399-1). LTA4H was detected in a paraffin-embedded section of human intestinal cancer tiss
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000111144-LTA4H/tissue/cerebral+cortex#imid_4368852
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000111144-LTA4H/tissue/colon#imid_2607170
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000111144-LTA4H/tissue/liver#imid_2607163
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000111144-LTA4H/tissue/kidney#imid_2607172
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA008399; green = LTA4H, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA008399; green = LTA4H, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for LTA4H IHC & IF
🧪Run esophagus first and expect staining in its squamous epithelial cells (HPA: High in esophageal squamous epithelial cells). HPA detects LTA4H in all 45 scored tissues, so there is no supported negative tissue; use no-primary and isotype controls, and expect little background in unstained spaces within the positive section without treating other cells as confirmed negatives (HPA: detected in all 45 scored tissues; standard IHC control practice).
Positive control tissue: Adrenal gland (Glandular cells, HPA High)
Negative control tissue: None in HPA: LTA4H is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead.
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show LTA4H in A-431, PC-3, U2OS, KOLF2.1J, with annotated localisation: Cytosol (supported) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only slide, a concentration-matched rabbit IgG isotype control matched to the primary antibody’s clonality where known, and LTA4H-knockout material as a biological negative if available (selected-SKU caption: rabbit primary; standard IHC control practice). For esophageal sections, quench endogenous peroxidase before HRP/DAB detection and check tissue autofluorescence if using IF (selected-SKU caption: HRP/DAB detection; standard IHC/IF practice).
⚠️Feasibility: No target-specific fixation window or fixation effect is reported, and the selected-SKU paraffin-section caption does not state the fixative (selected-SKU caption: fixative unreported). Its demonstrated IHC procedure uses heat-mediated EDTA retrieval at pH 8.0, so assess retrieval under the local processing conditions (selected-SKU caption: EDTA pH 8.0). HPA supports cytosolic ICC-IF localization, but the supplied evidence does not establish that frozen sections or IF are easier than paraffin IHC; assess esophageal background with the detection-specific controls above (HPA: cytosol supported; standard IHC/IF practice).
HPA tissue IHC evidence for LTA4H
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Supported — 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 → |
| Bone marrow | Hematopoietic cells | High | Protein (IHC) | HPA → |
| Cervix | Glandular cells | High | Protein (IHC) | HPA → |
| Epididymis | Glandular cells | High | Protein (IHC) | HPA → |
| Esophagus | Squamous epithelial cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| None in HPA: LTA4H is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead. | ||||
Section 3
Advanced LTA4H IHC Tips
Troubleshoot LTA4H staining in paraffin sections by checking retrieval, cell identity, compartment, and detection controls before comparing signal across samples.
What retrieval should I start with for weak LTA4H staining?
Start with heat-mediated retrieval in EDTA at pH 8.0 for paraffin sections (datasheet A02399-1). The selected tissue image used this retrieval before overnight incubation at 4°C with 2 μg/ml primary antibody (datasheet A02399-1). If staining is weak, first check that heating and subsequent cooling are consistent across slides, then compare retrieval duration on adjacent sections while holding detection conditions constant (standard IHC practice). Assess signal in esophageal squamous epithelium or lung macrophages, both reported as high-expressing populations, and check for increased background alongside any gain in target staining (HPA tissue IHC; standard IHC practice).
How should I troubleshoot inconsistent staining after fixation?
Target-specific fixation sensitivity for LTA4H is unknown from the supplied evidence; the selected paraffin-section caption does not state its fixative (datasheet A02399-1). Record fixative, fixation duration, tissue thickness, and processing history for each specimen, then compare sections processed together under identical retrieval and detection conditions (standard IHC practice). If signal differs between batches, use a consistently processed reference section to test whether the difference follows processing rather than specimen identity (standard IHC practice). Do not assign the difference to LTA4H acetylation, phosphorylation, or cytoplasmic location without a controlled comparison; those features are annotated, but their effects on fixation sensitivity are unreported (UniProt P09960).
Should LTA4H staining appear in nuclei or cytoplasm?
Expect predominantly cytoplasmic staining: UniProt assigns LTA4H to the cytoplasm, and HPA reports a supported cytosolic main location (UniProt P09960; HPA subcellular). HPA also describes nuclear and cytoplasmic tissue staining, while its additional nucleoplasmic location is uncertain (HPA tissue IHC; HPA subcellular). When nuclei stain strongly, compare the nuclear signal with cytoplasmic signal in the same cell population and inspect a no-primary control for detection background (standard IHC practice). Treat a purely nuclear pattern cautiously, particularly if expected positive cell populations lack cytoplasmic signal; document both compartments separately before interpreting the result (HPA subcellular; standard IHC practice).
Can this antibody distinguish LTA4H isoforms in tissue?
The supplied record lists 4 LTA4H isoforms, but gives no mapped epitope or isoform-specific reactivity for the catalog antibody (UniProt P09960; datasheet A02399-1). Isoforms 1 and 2 are reported in monocytes, lymphocytes, neutrophils, reticulocytes, platelets, and fibroblasts, so staining in those populations cannot by itself identify an isoform (UniProt P09960). LTA4H has no annotated transmembrane segment or glycosylation sites, but its listed acetylated and phosphorylated residues do not establish whether this antibody recognizes a modified epitope (UniProt P09960). Score staining as total antibody-reactive LTA4H unless epitope mapping and isoform-specific controls establish narrower specificity (standard IHC interpretation).
How can IF help check which cells contain LTA4H?
On the separate IF/ICC workflow, multiplex LTA4H with a marker for the expected population, such as CD68 for lung macrophages, and include single-label controls to assess channel overlap (HPA tissue IHC: high in lung macrophages; standard IF practice). Select spectrally separated fluorophores after examining tissue autofluorescence, and compare each channel with an appropriate unstained or no-primary control (standard IF practice). Because LTA4H is mainly cytosolic and has no transmembrane segment, permeabilisation must permit antibody access to intracellular antigen; optimise it for the chosen fixation method (HPA subcellular; UniProt P09960; standard IF practice). The supplied evidence does not establish IF/ICC fixation conditions or fluorophore settings for this antibody (datasheet A02399-1).
How do I reduce diffuse brown background in LTA4H IHC?
First compare a no-primary section with the stained section to distinguish detection background from antibody-associated signal (standard IHC practice). The selected image used 10% goat serum blocking, 2 μg/ml primary antibody overnight at 4°C, and a peroxidase-linked detection system with DAB (datasheet A02399-1). Include an endogenous peroxidase block and adjust washing or primary concentration through controlled comparisons if diffuse color persists; these are general chromogenic IHC measures (standard IHC practice). Inspect pigment, necrosis, and tissue edges before scoring, and retain cytoplasmic signal in expected cell populations only when it exceeds the matched control (HPA subcellular; standard IHC practice).
What should I quantify when comparing LTA4H between sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and compartment before scoring, because LTA4H is mainly cytosolic and tissue sections can contain several stained cell types (HPA subcellular; HPA tissue IHC). For epithelial or other defined populations, report the percentage of positive cells and an H-score based on intensity and positive fraction; apply the same thresholds across slides (standard IHC practice). For discrete immune-cell populations, report positive-cell density per mm² of viable tissue or the percentage positive among that cell type (standard IHC practice). Normalise comparisons to the same eligible tissue area, cell denominator, staining batch, and reference section, excluding necrosis and edge artefacts consistently (standard IHC practice).
How can I tell true LTA4H signal from artefact?
A plausible result includes cytoplasmic staining in an expected population, such as lung macrophages or esophageal squamous epithelial cells, both reported with high expression (HPA subcellular; HPA tissue IHC). Check whether apparent signal is limited to section edges, necrotic regions, pigment, or a no-primary control; those patterns warrant investigation before calling cells positive (standard IHC practice). Strong isolated nuclear staining deserves caution because the supported main location is cytosolic and the additional nucleoplasmic assignment is uncertain (HPA subcellular). Peroxidase-associated color can reflect endogenous enzyme activity, so interpret DAB staining against a peroxidase-blocked control and cell morphology rather than color alone (standard IHC practice).
Boster reagents
Best LTA4H / Leukotriene A-4 hydrolase IHC Antibodies
A02399-1 has pictured IHC and IF in human paraffin sections (IHC/IF image captions). Both antibodies list human, mouse, and rat reactivity (catalog reactivity).
Real IHC data
Anti-LTA4H Antibody ®
Cat # A02399-1
A02399-1 has pictured IHC in human esophageal squamous carcinoma paraffin sections and pictured IF in human intestinal cancer paraffin sections (IHC/IF image captions). M02399-3 lists IHC and ICC/IF applications with human, mouse, and rat reactivity, but has no IHC or IF image captions in the payload (catalog applications/reactivity; image captions: none).
Which to pick: For tissue IHC, choose A02399-1: its human paraffin-section caption documents EDTA retrieval at pH 8.0 and 2 μg/ml primary antibody; the fixative is unreported (A02399-1 IHC image caption). For IF on paraffin sections, A02399-1 has a pictured example; for ICC, M02399-3 lists that application without a pictured example (A02399-1 IF image caption; M02399-3 catalog applications/image captions). For mouse or rat work, both list reactivity; choose M02399-3 if a rabbit monoclonal is needed, while recognizing that the supplied IHC/IF images document human samples only (catalog reactivity/host/clone; image captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P09960 (LKHA4_HUMAN, Leukotriene A-4 hydrolase).
- Human Protein Atlas. LTA4H tissue IHC expression (reliability: Supported).
- Human Protein Atlas. LTA4H subcellular location (ICC-IF): Mainly localized to the cytosol. In addition localized to the nucleoplasm..
- Human Protein Atlas. LTA4H antibody validation summary (3 antibodies).
- Molecular and Immunohistochemical Expression of LTA4H and FXR1 in Canine Oral Melanoma. Frontiers in veterinary science 2021 — PMC8710725.
- Inhibition of LTA4H by bestatin in human and mouse colorectal cancer. EBioMedicine 2019 — PMC6604047.
- Immunohistochemical localization of key arachidonic acid metabolism enzymes during fracture healing in mice. PloS one 2014 — PMC3917894.
- Alpha-Lipoic Acid-Mediated Inhibition of LTB(4) Synthesis Suppresses Epithelial-Mesenchymal Transition, Modulating Functional and Tumorigenic Capacities in Non-Small Cell Lung Cancer A549 Cells. Current therapeutic research, clinical and experimental 2025 — PMC11731977.
- PubMed PMID:3654641 — UniProt-cited evidence.
- PubMed PMID:2821541 — UniProt-cited evidence.
- PubMed PMID:7628486 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for LTA4H (Leukotriene A-4 hydrolase). Expected localisation Nuclear and cytoplasmic staining in most tissues (HPA tissue IHC). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A02399-1). Validated IHC antibody: A02399-1 at 1-2 μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Adrenal gland (Glandular cells); negative None in HPA (detected in all 45 tissues); use no-primary + isotype controls. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human esophageal squamous carcinoma tissue; fixative not specified (datasheet A02399-1); 2. Fixation: Image fixative and duration unreported (datasheet A02399-1); 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 A02399-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A02399-1); 8. Primary antibody: Rabbit anti-LTA4H, 1-2 μg/ml (datasheet A02399-1); 9. Primary incubation: Overnight at 4 °C (datasheet A02399-1). Watch for: Fixation: Keep fixation consistent across sections (standard IHC practice; not target-specific); Caveat: Strong lung macrophage staining may complicate scoring (HPA tissue IHC); Isoform / epitope: 4 isoforms; antibody epitope coverage is unknown (UniProt); Regulation: No specific expression regulator reported (UniProt). Evidence: UniProt P09960, HPA tissue IHC · Supported, HPA ICC-IF · Mainly localized to the cytosol. In addition localized to the…, Datasheet A02399-1, PMC8710725, PMC3917894. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/LTA4H/immunohistochemistry-ihc-guide.