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ALDH7A1 / Alpha-aminoadipic semialdehyde dehydrogenase · IHC design guide
Design Immunohistochemistry for ALDH7A1
Plan chromogenic ALDH7A1 IHC on paraffin sections with the catalog antibody at 0.5–1 μg/mL (datasheet PB10038). Assess cytoplasmic, mitochondrial-pattern staining using kidney proximal tubules or liver cholangiocytes as positive controls (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
ALDH7A1 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 with a mitochondrial pattern (HPA tissue IHC) | |
| Staining pattern | Cytoplasmic, mitochondrial-pattern staining in most tissues (HPA tissue IHC) | |
| Antigen retrieval | Citrate pH 6 HIER, heat-mediated (datasheet PB10038) | |
| Positive control | Cerebellum+4 more · see all | |
| 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 | Antibody staining and RNA have medium consistency (HPA tissue IHC) | |
| Regulation | Tissue-enhanced RNA in liver (HPA tissue RNA) | |
| Isoform / epitope | 3 isoforms; chain begins at residue 27; check epitope coverage (UniProt) |
Section 1
Recommended ALDH7A1 IHC & IF Protocols
The catalog antibody’s IHC-P protocol (datasheet PB10038) is paired with four published ALDH7A1 tissue protocols (PMC3458927; PMC6264057; PMC7847681; PMC5341386).
| Sample | Paraffin-embedded human lung cancer tissues; fixative not specified (datasheet PB10038) |
| Fixation | Image fixative and duration unreported (datasheet PB10038); 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 PB10038) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet PB10038) |
| Primary antibody | Rabbit anti-ALDH7A1, 0.5-1μg/ml (datasheet PB10038) |
| Primary incubation | Overnight at 4 °C (datasheet PB10038) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet PB10038) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | ALDH7A1-positive staining in bergmann glia - cytoplasm/membrane of cerebellum (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression with a mitochondrial pattern in most tissues. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated citrate pH 6 retrieval (datasheet PB10038); the published steamer and automated protocols provide tissue-specific starting conditions (PMC5341386; PMC7847681).
Section 2
What Is the Expected ALDH7A1 Staining Pattern?
ALDH7A1 is mainly mitochondrial, with additional cytosolic localization (HPA: supported ICC-IF locations); UniProt also lists the nucleus and cell and Golgi membranes, with no transmembrane segment (UniProt P49419). In tissue IHC, expect cytoplasmic staining with a mitochondrial pattern, especially in kidney proximal tubules, liver cholangiocytes, placenta cytotrophoblasts, and cerebellar Bergmann glia (HPA: High). HPA rates tissue staining Enhanced, with medium consistency against RNA expression (HPA: tissue IHC).
| Granular cytoplasmic staining in kidney proximal tubules or liver cholangiocytes, with little signal in adjacent cells. | This fits the reported mitochondrial-pattern cytoplasm and High staining in those cell types (HPA: tissue IHC). Compare cell types within the section rather than treating all tissue as uniformly positive. |
| Predominantly nuclear staining, with little cytoplasmic signal. | This does not match the principal tissue IHC pattern (HPA: tissue IHC). Nuclear localization is listed by UniProt, so compartment alone cannot prove artefact; check whether known-positive cells also show the expected cytoplasmic pattern (UniProt P49419; HPA: tissue IHC). |
| Strong staining in adipocytes, lung alveolar cells, or ovarian follicle cells. | These cell types are Not detected in HPA tissue IHC (HPA: adipose tissue, lung, ovary). Consider nonspecific antibody binding or endogenous detection activity, especially if the expected positive cell types are absent (general IHC practice). |
| Diffuse color across tissue and blank areas, obscuring cell boundaries. | This is difficult to assign to the reported cell-specific cytoplasmic pattern (HPA: tissue IHC). Background can arise from nonspecific binding or detection chemistry; a negative reagent control helps separate it from cellular staining (general IHC practice). |
| No signal in kidney proximal tubules or liver cholangiocytes. | Both are reported High by HPA (HPA: kidney, liver tissue IHC). First assess tissue preservation and the run’s positive control, then review antibody and detection steps; a blank slide alone does not establish absent ALDH7A1 (general IHC practice). |
💡Expected ALDH7A1 appearanceCall a result positive when defined cells show cytoplasmic, often granular mitochondrial-pattern staining—potentially High in kidney proximal tubules or liver cholangiocytes (HPA: tissue IHC); uniform background or strong staining in HPA-undetected cell types is suspect (HPA: tissue IHC; general IHC practice).
| Compartment and topology (UniProt P49419; HPA: subcellular ICC-IF) | Mitochondria are the supported main location, with cytosol also supported (HPA: subcellular ICC-IF). No transmembrane segment is annotated, so membrane-like staining alone should not replace the expected cytoplasmic assessment (UniProt P49419; HPA: tissue IHC). |
| Cell-type variation (HPA: tissue IHC) | HPA reports High staining in selected cells, Medium in others, and undetected staining in several cell types (HPA: tissue IHC). Score the named cells and compartment; whole-section intensity can hide this variation (general IHC practice). |
| Stress-linked localization (UniProt P49419) | UniProt reports translocation to membranes with cellular stress and AMPK phosphorylation (UniProt P49419). This may inform an unusual localization, but the supplied tissue IHC record does not show how often that pattern occurs in sections (HPA: tissue IHC). |
| Antibody evidence (HPA: antibody validation; tissue IHC) | Two listed rabbit polyclonal antibodies, HPA023296 and HPA053675, have Enhanced IHC validation (HPA: antibodies). HPA describes medium staining-to-RNA consistency, so validation supports the pattern without making every observed stain specific (HPA: tissue IHC). |
| IF/ICC Q&A: What localization should an IF image show? (HPA: subcellular ICC-IF) | Mainly mitochondria, with additional cytosol (HPA: supported ICC-IF locations). This is an IF/ICC interpretation cue; judge paraffin chromogenic IHC against the tissue cell-type pattern instead (HPA: tissue IHC). |
| Situation | Likely cause | Next action |
|---|---|---|
| Known-positive kidney or liver cells are blank (HPA: kidney, liver tissue IHC). | The run may have failed, or target detection may be inadequate; the slide does not distinguish these causes (general IHC practice). | Check the run’s positive control and section quality, then review primary antibody, retrieval, and detection steps against the established IHC procedure (general IHC practice). ALDH7A1-specific retrieval sensitivity is unreported here. |
| Color covers negative reagent controls as well as tissue. | Detection-system background or nonspecific deposition is possible (general IHC practice). | Review blocking, washes, and chromogen development with an appropriate negative control (general IHC practice); do not score diffuse color as the HPA cytoplasmic pattern (HPA: tissue IHC). |
| Strong nuclear signal dominates the section. | The result differs from HPA’s principal cytoplasmic mitochondrial-pattern IHC, although UniProt lists a nuclear location (HPA: tissue IHC; UniProt P49419). | Inspect whether HPA-positive cell types also retain cytoplasmic staining, and compare a negative reagent control before assigning the nuclear signal to ALDH7A1 (HPA: tissue IHC; general IHC practice). |
| Undetected reference cells stain as strongly as expected positive cells. | Nonspecific binding or endogenous detection activity may contribute (general IHC practice); HPA lists adipocytes and lung alveolar cells as Not detected (HPA: tissue IHC). | Check cell identity, compare controls, and inspect staining with the primary antibody omitted (general IHC practice). Reassess whether the expected positive cells retain the reported compartment pattern (HPA: tissue IHC). |
| Only faint, uniform cytoplasmic color is visible. | The expected cell-to-cell contrast may be obscured by background or weak detection (HPA: tissue IHC; general IHC practice). | Compare proximal tubules or cholangiocytes with nearby cells and the run controls (HPA: kidney, liver tissue IHC; general IHC practice). Adjust staining conditions only within a validated IHC workflow (general IHC practice). |
| A distinct membrane-like pattern appears without the usual cytoplasmic pattern. | UniProt reports stress-associated membrane translocation, but the tissue IHC profile emphasizes cytoplasmic staining (UniProt P49419; HPA: tissue IHC). | Record the compartment and cell type, review controls, and interpret cautiously; the supplied evidence does not establish that membrane-only chromogenic staining is a routine positive result (HPA: tissue IHC; UniProt P49419). |
Experiment evidence
IHC & IF images showing ALDH7A1 staining
PB10038 · IHCIHC analysis of ALDH7A1 using anti-ALDH7A1 antibody (PB10038). ALDH7A1 was detected in paraffin-embedded section of human lung cancer tissue
PB10038 · IHCIHC analysis of ALDH7A1 using anti-ALDH7A1 antibody (PB10038). ALDH7A1 was detected in paraffin-embedded section of rat brain tissues. Heat
PB10038 · IFIF analysis of ALDH7A1 using anti-ALDH7A1 antibody (PB10038). ALDH7A1 was detected in immunocytochemical section of U20S cell. Enzyme antige
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000164904-ALDH7A1/tissue/cerebral+cortex#imid_21010747
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000164904-ALDH7A1/tissue/colon#imid_21013273
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000164904-ALDH7A1/tissue/liver#imid_21013274
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000164904-ALDH7A1/tissue/kidney#imid_21013275
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA023296; green = ALDH7A1, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA023296; green = ALDH7A1, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for ALDH7A1 IHC & IF
🧪Run kidney first: proximal tubule cell bodies should stain (HPA: High in kidney proximal tubules). Use adipose tissue as the negative tissue (HPA: adipocytes Not detected); on the kidney slide, cells without specific staining should show only background, but the supplied HPA rows do not identify a kidney cell type to designate as an internal negative.
Positive control tissue: Cerebellum (Bergmann glia - cytoplasm/membrane, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show ALDH7A1 in A-431, U-251MG, U2OS, NIH 3T3, with annotated localisation: Mitochondria (supported) (HPA subcellular).
Technical controls: Include no-primary (secondary-only) and rabbit IgG controls matched to the primary antibody’s clonality when known (selected-SKU caption: rabbit primary); confirm specificity with ALDH7A1 knockout material or a validated peptide block (standard IHC practice). Quench endogenous peroxidase and block endogenous biotin when using the caption’s avidin–biotin/DAB detection method, particularly in kidney tissue (selected-SKU caption: SABC with DAB; standard IHC practice).
⚠️Feasibility: A target-specific fixation window and fixation effect are unreported in the supplied evidence; the selected-SKU paraffin-section caption does not state the fixative (selected-SKU caption: fixative unreported). The demonstrated IHC retrieval condition is heat-mediated citrate buffer at pH 6 for 20 minutes, but the evidence does not establish whether retrieval is required under other conditions (selected-SKU caption). ICC-IF images support evaluating mitochondrial and cytosolic signal, while no supplied evidence establishes that frozen sections or IF are easier than paraffin IHC; kidney tubules warrant attention to endogenous biotin if using SABC (HPA: mitochondrial and cytosolic localization; HPA: ICC-IF images; selected-SKU caption: SABC; standard IHC practice).
HPA tissue IHC evidence for ALDH7A1
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 |
|---|---|---|---|---|
| Cerebellum | Bergmann glia - cytoplasm/membrane | High | Protein (IHC) | HPA → |
| Kidney | Proximal tubules (cell body) | High | Protein (IHC) | HPA → |
| Liver | Cholangiocytes | High | Protein (IHC) | HPA → |
| Placenta | Cytotrophoblasts | High | Protein (IHC) | HPA → |
| Adrenal gland | Glandular cells | Medium | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Bone marrow | Hematopoietic cells | Not detected | Protein (IHC) | HPA → |
| Cervix | Squamous epithelial cells | Not detected | Protein (IHC) | HPA → |
| Duodenum | Endocrine cells | Not detected | Protein (IHC) | HPA → |
| Lung | Alveolar cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced ALDH7A1 IHC Tips
Troubleshoot ALDH7A1 staining in paraffin sections by checking retrieval, cell identity, subcellular pattern and detection controls together.
How should I retrieve ALDH7A1 in paraffin sections when staining is weak?
Start with heat-mediated retrieval in citrate buffer at pH 6 (datasheet PB10038). The selected paraffin-section example heated tissue for 20 minutes before applying the catalog antibody at 1 μg/mL overnight at 4°C (caption PB10038). Keep section thickness, heating and cooling consistent across controls so a retrieval change can be distinguished from uneven processing (standard IHC practice). If staining remains weak, compare a modestly adjusted heating time on serial sections while monitoring tissue damage (standard IHC practice). Judge any gain in the expected cytoplasmic, mitochondrial-pattern staining rather than in diffuse background (HPA tissue IHC: cytoplasmic expression with a mitochondrial pattern).
Could fixation explain weak or uneven ALDH7A1 staining?
Target-specific fixation sensitivity is unknown: the selected paraffin-section caption does not state a fixative (caption PB10038). Record each specimen’s fixative and fixation interval, then compare similarly processed sections before attributing a difference to ALDH7A1 abundance (standard IHC practice). Use the same citrate pH 6 retrieval and detection conditions across that comparison (datasheet PB10038; standard IHC practice). If morphology is preserved but staining differs, examine processing history, section age and a concurrently stained positive control (standard IHC practice). HPA staining patterns and the protein’s reported locations cannot establish how fixation affects this antibody’s epitope (HPA tissue IHC: staining profile; UniProt P49419: subcellular locations).
What staining pattern should count as plausible ALDH7A1 localisation?
Expect predominantly cytoplasmic staining with a mitochondrial pattern in tissue sections (HPA tissue IHC: cytoplasmic expression with a mitochondrial pattern). Supported cell imaging also places ALDH7A1 mainly in mitochondria and additionally in cytosol (HPA subcellular: supported locations). UniProt reports nuclear, cell-membrane and Golgi-membrane locations, plus stress-associated membrane translocation after AMPK phosphorylation (UniProt P49419: subcellular locations). Because ALDH7A1 has no annotated transmembrane segment, a sharp membrane rim alone warrants scrutiny before it is scored as specific (UniProt P49419: topology; standard IHC practice). Compare suspected nuclear or membrane staining with cytoplasmic signal, tissue morphology and a no-primary control on adjacent sections (standard IHC practice).
How can isoforms or epitope accessibility change the IHC result?
ALDH7A1 has three listed isoforms, numbered 1, 2 and 4 (UniProt P49419: isoforms). Its annotated mature chain spans residues 27–539, and reported modifications include AMPK phosphorylation at residue 130 (UniProt P49419: processing and modified residues). Without an epitope map for PB10038 in the supplied evidence, do not assume that every isoform or modified state is detected equally (caption PB10038: antibody identity; standard antibody-validation practice). Compare serial sections under identical citrate pH 6 retrieval and staining conditions before interpreting a regional loss as isoform-specific (datasheet PB10038; standard IHC practice). An independent antibody with a documented, distinct epitope can help test that interpretation (standard antibody-validation practice).
How should I check an unexpected IHC pattern with multiplex IF?
Use companion IF/ICC as a localisation check for the chromogenic IHC finding, pairing ALDH7A1 with a marker of the expected cell type, such as cholangiocytes in liver (HPA tissue IHC: high in cholangiocytes). Choose separated fluorophores and inspect unstained tissue in each channel before selecting wavelengths, because tissue autofluorescence can mimic puncta (standard IF practice). For a cytosolic or mitochondrial epitope, optimise mild permeabilisation and confirm that the antibody can access its epitope; its precise membrane-facing side is not supplied (HPA subcellular: mitochondria and cytosol; standard IF practice). Compare the IF compartment pattern with adjacent IHC sections and include single-label and no-primary controls (standard IF practice).
How do I separate ALDH7A1 signal from chromogenic background?
The selected paraffin-section example used a biotinylated secondary, streptavidin-biotin detection and DAB (caption PB10038). Include a peroxidase block before DAB development and a no-primary section to assess detection background (standard chromogenic IHC practice). If a biotin-based system stains the no-primary section, test an avidin-biotin block or a polymer detection system on matched sections (standard IHC practice). Titrate primary antibody around the reported 1 μg/mL condition while holding development time constant (caption PB10038; standard IHC practice). Retain staining only when cell morphology and the expected cytoplasmic, mitochondrial pattern remain discernible above background (HPA tissue IHC: staining profile; standard IHC practice).
How should I quantify ALDH7A1 across heterogeneous tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and region before scoring, then report percent positive cells and staining intensity separately (standard IHC scoring practice). For an H-score, assign intensities 0–3 and sum each intensity multiplied by its percentage of cells, giving a 0–300 range (standard H-score practice). Where cell density varies, also report positive cells per mm² of evaluable tissue and the number of cells assessed (standard image-analysis practice). Normalise comparisons to the same cell type, viable tissue area and staining batch, with matched exposure or scan settings (standard IHC quantification practice). Keep cholangiocytes distinct from other liver cells because their ALDH7A1 staining is reported as high (HPA tissue IHC: cholangiocytes).
When is an ALDH7A1-positive area likely to be artefact?
A convincing result follows viable cell boundaries and shows cytoplasmic staining with a mitochondrial pattern (HPA tissue IHC: staining profile; standard IHC interpretation practice). Recheck isolated nuclear or sharply peripheral signal against the dominant pattern, while allowing that additional locations are reported (UniProt P49419: subcellular locations). Exclude torn edges and necrotic regions from scoring, and investigate staining that persists without primary antibody or after the peroxidase control (standard IHC practice). The PB10038 image documents staining in a human lung cancer paraffin section, whereas HPA reports no detection in normal lung alveolar cells; these are different tissue contexts (caption PB10038; HPA tissue IHC: alveolar cells). Interpret discordance using matched morphology, controls and the scored cell population (standard IHC practice).
Boster reagents
Best ALDH7A1 / Alpha-aminoadipic semialdehyde dehydrogenase IHC Antibodies
PB10038 has IHC images from human lung cancer and rat brain paraffin sections, plus an IF/ICC image from U20S cells (PB10038 image captions).
Real IHC data
Anti-ALDH7A1 Antibody ®
Cat # PB10038
The rendered SKU, PB10038, has IHC images from human lung cancer and rat brain paraffin sections (PB10038 IHC captions). Its IF/ICC image shows U20S cells, and its stated reactivity covers human, mouse and rat (PB10038 IF caption; PB10038 catalog data).
Which to pick: Choose PB10038 for paraffin-section tissue IHC: its captions document citrate retrieval at pH 6 for 20 minutes and 1 μg/ml primary antibody in human lung cancer and rat brain sections (PB10038 IHC captions). For IF/ICC, PB10038 has an image from U20S cells using 2 μg/ml primary antibody (PB10038 IF caption). For cross-species work, PB10038 lists human, mouse and rat reactivity, while its IHC-P details cover human and rat; the IHC captions do not report a fixative (PB10038 catalog data; PB10038 IHC captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P49419 (AL7A1_HUMAN, Alpha-aminoadipic semialdehyde dehydrogenase).
- Human Protein Atlas. ALDH7A1 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. ALDH7A1 subcellular location (ICC-IF): Mainly localized to the mitochondria. In addition localized to the cytosol..
- Human Protein Atlas. ALDH7A1 antibody validation summary (2 antibodies).
- Characterization of aldehyde dehydrogenase isozymes in ovarian cancer tissues and sphere cultures. BMC cancer 2012 — PMC3458927.
- Metabolic control of PPAR activity by aldehyde dehydrogenase regulates invasive cell behavior and predicts survival in hepatocellular and renal clear cell carcinoma. BMC cancer 2018 — PMC6264057.
- Overall survival of pancreatic ductal adenocarcinoma is doubled by Aldh7a1 deletion in the KPC mouse. Theranostics 2021 — PMC7847681.
- ALDH7A1 expression is associated with recurrence in patients with surgically resected non-small-cell lung carcinoma. Future oncology (London, England) 2013 — PMC5341386.
- PubMed PMID:8088832 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
- PubMed PMID:15372022 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for ALDH7A1 (Alpha-aminoadipic semialdehyde dehydrogenase). Expected localisation Cytoplasmic with a mitochondrial pattern (HPA tissue IHC). Antigen retrieval: Citrate pH 6 HIER, heat-mediated (datasheet PB10038). Validated IHC antibody: PB10038 at 0.5-1μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Cerebellum (Bergmann glia - cytoplasm/membrane); negative Adipose tissue. IHC workflow; specimen preparation unspecified. Protocol steps: 1. Sample: Paraffin-embedded human lung cancer tissues; fixative not specified (datasheet PB10038); 2. Fixation: Image fixative and duration unreported (datasheet PB10038); 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 PB10038); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet PB10038); 8. Primary antibody: Rabbit anti-ALDH7A1, 0.5-1μg/ml (datasheet PB10038); 9. Primary incubation: Overnight at 4 °C (datasheet PB10038). Watch for: Fixation: Keep fixation conditions consistent across sections. (standard IHC practice; not target-specific); Caveat: Antibody staining and RNA have medium consistency (HPA tissue IHC); Isoform / epitope: 3 isoforms; chain begins at residue 27 ; check epitope coverage (UniProt); Regulation: Tissue-enhanced RNA in liver (HPA tissue RNA). Evidence: UniProt P49419, HPA tissue IHC · Enhanced, HPA ICC-IF · Mainly localized to the mitochondria. In addition localized to the…, Datasheet PB10038, PMC3458927, PMC6264057. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/ALDH7A1/immunohistochemistry-ihc-guide.