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SNCA / Alpha-synuclein · IHC design guide
Design Immunohistochemistry for SNCA
Plan chromogenic SNCA IHC in paraffin sections using CNS neuropil and marrow cell staining as reference patterns (HPA tissue IHC). This guide covers controls, localisation and a 1:50 starting dilution for the IHC-validated antibody (datasheet M00215-1).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
SNCA 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 | Presynaptic terminals; cytoplasm, membrane and nucleus (UniProt) | |
| Staining pattern | High in CNS neuropil, peripheral nerves and marrow cell subsets (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet M00215-1) | |
| Positive control | Bone marrow+3 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 consistent across sections (standard IHC practice; not target-specific) | |
| Caveat | Glia may be negative despite strong CNS neuropil staining (HPA tissue IHC) | |
| Regulation | Enriched in brain and presynaptic terminals (UniProt) | |
| Isoform / epitope | Three isoforms; epitope coverage depends on antibody specificity (UniProt) |
Section 1
Recommended SNCA IHC & IF Protocols
The catalog antibody has a paraffin-section protocol (datasheet: M00215-1). Published IHC examples cover mouse brain and spinal cord (PMC4986551), human brain (PMC4549856), and lung adenocarcinoma slides (PMC9009002).
| Sample | Paraffin-embedded human glioma tissue; fixative not specified (datasheet M00215-1) |
| Fixation | Image fixative and duration unreported (datasheet M00215-1); 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 M00215-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet M00215-1) |
| Primary antibody | Rabbit monoclonal (clone AGA-19) anti-SNCA, 1:50 (datasheet M00215-1) |
| Primary incubation | Overnight at 4 °C (datasheet M00215-1) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet M00215-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | SNCA-positive staining in hematopoietic cells of bone marrow (HPA tissue IHC: High). HPA tissue profile: High expression in CNS and peripheral nerves, as well as subsets of cells in bone marrow. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA pH 8.0 retrieval for the catalog antibody (datasheet: M00215-1); citrate microwave retrieval is a published alternative for lung adenocarcinoma slides (PMC9009002).
Section 2
What Is the Expected SNCA Staining Pattern?
SNCA is enriched at presynaptic terminals in the central nervous system and is also annotated in cytoplasm, membrane, nucleus, synapses and axons; it has no transmembrane segment (UniProt P37840). In tissue IHC, expect strong neuropil staining in cerebral cortex, staining of cerebellar granular-layer processes, and staining in subsets of bone-marrow hematopoietic cells (HPA: Enhanced tissue reliability; High cortical neuropil and bone-marrow staining; Medium cerebellar process staining).
| Cortical neuropil stains strongly while neuronal processes are more apparent than cell bodies. | This fits the reported High cortical neuropil signal and presynaptic enrichment (HPA: High in cerebral-cortex neuropil; UniProt P37840: presynaptic terminals). Interpret staining by structure as well as intensity; a field of positive processes need not show uniformly positive nuclei or somata. |
| Staining is confined to a compartment inconsistent with the sampled structure, with no expected neuropil or process signal. | Reassess localisation before calling the section positive: cytoplasm, membrane, nucleus, synapse and axon are annotated, so nuclear signal alone is not proof of artefact (UniProt P37840). A compartment-only pattern that misses the expected tissue structures raises concern for an IHC artefact (HPA: cortical neuropil and cerebellar processes). |
| Strong signal appears in cells reported as unstained, such as adipocytes or duodenal glandular cells. | Those specific cell populations are Not detected in HPA tissue IHC (HPA: adipose adipocytes; duodenal glandular cells). Check cross-reactivity and endogenous detection activity as possible explanations (general IHC practice). Do not label an entire tissue negative when its documented negative call applies to a named cell type. |
| A diffuse chromogenic haze covers positive and expected-negative structures alike. | A uniform haze obscures the contrast needed to recognize High cortical neuropil and Not detected adipocytes (HPA: cerebral-cortex neuropil; adipose adipocytes). Treat the pattern as background until the expected anatomical contrast is visible; review blocking, detection background and primary-antibody concentration (general IHC practice). |
| A cerebral-cortex positive control shows no neuropil staining. | That conflicts with the reported High cortical neuropil staining (HPA: cerebral cortex). First check that the expected structure is present on the section, then review the staining run and the catalog antibody's IHC-P directions (general IHC practice). An absent control signal makes negative calls in test sections unreliable. |
💡Expected SNCA appearanceCall a positive result when cortical neuropil shows clear, strong, anatomically defined signal (HPA: High in cerebral-cortex neuropil); broad haze or strong staining of documented Not detected cell types is suspect (HPA: adipose adipocytes; general IHC practice).
| Anatomical compartment | SNCA is enriched in presynaptic terminals and annotated in synapses and axons (UniProt P37840). Score signal in neuropil and processes rather than requiring a uniformly filled neuronal soma (HPA: cortical neuropil; cerebellar granular-layer processes). |
| Tissue and cell-type contrast | HPA reports High signal in cortical neuropil, bone-marrow hematopoietic cells and kidney glomerular cells, Medium signal in cerebellar granular-layer processes, and Not detected signal in listed adipocytes (HPA: tissue IHC). These calls apply to the specified structures or cells. |
| Antibody validation | Two listed antibodies have Enhanced IHC status (HPA: HPA005459 and CAB010877). The tissue profile also has Enhanced reliability, reflecting consistency with RNA data; HPA notes staining in structures outside its annotations, so review the image when a structure is uncertain (HPA: tissue IHC). |
| Protein forms and epitope information | Three isoforms and several modified residues are annotated, including phosphoserine at position 129 (UniProt P37840). The supplied records give no antibody epitope or isoform specificity, so they cannot predict which form an IHC signal represents (UniProt P37840; HPA: antibody summary). |
| Retrieval and fixation | The supplied sources report no target-specific fixation sensitivity or retrieval condition (UniProt P37840; HPA: tissue IHC). Use the catalog antibody's IHC-P instructions for a starting workflow; assess retrieval changes with positive and expected-negative controls (general IHC practice). |
| Situation | Likely cause | Next action |
|---|---|---|
| No signal in cerebral-cortex neuropil | The positive control failed, the expected structure is absent, or a staining step failed (HPA: High cortical neuropil; general IHC practice). | Confirm neuropil is present; check reagent sequence, detection and the catalog antibody's IHC-P instructions before interpreting test sections (general IHC practice). |
| Signal fills the slide without anatomical contrast | Nonspecific binding or detection background can obscure structure-specific staining (general IHC practice). | Review blocking, washes and primary-antibody concentration; compare a control omitting primary antibody with the expected cortical neuropil pattern (general IHC practice; HPA: High cortical neuropil). |
| Adipocytes or duodenal glandular cells stain strongly | These named cells are Not detected in the HPA tissue profile; cross-reactivity or endogenous detection activity is possible (HPA: named negative cells; general IHC practice). | Inspect cell identity and the control omitting primary antibody, then review detection blocking and antibody conditions (general IHC practice). |
| Only nuclei stain in a cortical section | Nucleus is an annotated SNCA location, but nuclear-only staining does not reproduce the reported cortical neuropil pattern (UniProt P37840; HPA: High cortical neuropil). | Check the cortical positive control and inspect staining in neuropil; do not classify nuclear localisation alone as artefact (UniProt P37840; general IHC practice). |
| Cerebellar signal is weaker than cortical signal | HPA rates granular-layer processes Medium and cortical neuropil High; the comparison may reflect the reported tissue pattern (HPA: cerebellum; cerebral cortex). | Score the named structures separately. Investigate a failed run if the cortical positive control is also absent (HPA: tissue IHC; general IHC practice). |
| What should an IF/ICC image look like? | The supplied HPA subcellular record gives no main location or cell lines with ICC-IF images (HPA: subcellular record). | Use the separate IF/ICC guide for assay design. This tissue IHC pattern cannot establish an IF/ICC image pattern or protocol (HPA: tissue IHC and subcellular records). |
Experiment evidence
IHC & IF images showing SNCA staining
M00215-1 · IHCIHC analysis of SNCA using anti-SNCA antibody (M00215-1). SNCA was detected in a paraffin-embedded section of human glioma tissue. Heat medi
M00215-1 · IHCIHC analysis of SNCA using anti-SNCA antibody (M00215-1). SNCA was detected in a paraffin-embedded section of human colon cancer tissue. Hea
M00215-1 · IFImmunofluorescent analysis using the Antibody at 1:50 dilution.
A00215-3 · IHCIHC analysis of Alpha Synuclein/SNCA using anti-Alpha Synuclein/SNCA antibody (A00215-3). Alpha Synuclein/SNCA was detected in a paraffin-em
A00215-3 · IHCIHC analysis of Alpha Synuclein/SNCA using anti-Alpha Synuclein/SNCA antibody (A00215-3). Alpha Synuclein/SNCA was detected in a paraffin-em
A00215-3 · IFIF analysis of Alpha Synuclein/SNCA using anti-Alpha Synuclein/SNCA antibody (A00215-3). Alpha Synuclein/SNCA was detected in an immunocytoc
M00215-2 · IHCM00215-2 staining SNCA in Human skin tissue sections by Immunohistochemistry (IHC-P -paraformaldehyde-fixed, paraffin-embedded sections). Ti
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000145335-SNCA/tissue/cerebral+cortex#imid_20356589
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000145335-SNCA/tissue/colon#imid_20360171
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000145335-SNCA/tissue/liver#imid_20359452
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000145335-SNCA/tissue/kidney#imid_20359453
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for SNCA IHC & IF
🧪Run cerebral cortex first: the neuropil should stain strongly (HPA: High in cerebral cortex neuropil). Use adipose tissue as the negative tissue; adipocytes should remain at background (HPA: Not detected in adipocytes). On the cortex slide, cells without neuropil-associated staining should show only background chromogen, but their SNCA-negative status is not established by the HPA row (HPA: High in neuropil).
Positive control tissue: Bone marrow (Hematopoietic cells, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA carries no ICC-IF cell line for SNCA; derive a cell-line control from the positive tissue's cell type (Hematopoietic cells) and confirm it by RNA or western blot first.
Technical controls: Include a no-primary, secondary-only control and a rabbit IgG isotype control matched to the catalog antibody’s clonality (caption: rabbit anti-SNCA antibody); use an SNCA knockout specimen as a biological negative where available. Quench endogenous peroxidase for HRP–DAB detection, and assess tissue autofluorescence separately if using IF (caption: HRP–DAB detection; standard IHC/IF practice).
⚠️Feasibility: A target-specific fixation window and fixation effect are unreported, and the selected-SKU tissue-IHC caption does not state a fixative (caption: fixative not stated). The reported paraffin-section staining used heat retrieval in EDTA at pH 8.0 and antibody at 1:50 overnight at 4°C; retrieval dependence has not been established by a comparison (caption: retrieval and incubation conditions). The supplied evidence does not establish whether frozen sections or IF are easier; in cortex, score neuropil signal separately from individual cell bodies because the HPA-positive compartment is neuropil (HPA: High in cerebral cortex neuropil).
HPA tissue IHC evidence for SNCA
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — High consistency between antibody staining and RNA expression data. Antibody staining in cells/structures not annotated, view images.). 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 |
|---|---|---|---|---|
| Bone marrow | Hematopoietic cells | High | Protein (IHC) | HPA → |
| Cerebral cortex | Neuropil | High | Protein (IHC) | HPA → |
| Kidney | Cells in glomeruli | High | Protein (IHC) | HPA → |
| Cerebellum | Processes in granular layer | Medium | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adipose tissue | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Adrenal gland | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Appendix | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Breast | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Bronchus | Respiratory epithelial cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced SNCA IHC Tips
Troubleshoot SNCA staining by checking retrieval, compartment, cell identity and detection controls before comparing signal across paraffin sections.
What should I change when SNCA staining is weak after antigen retrieval?
Start with heat mediated retrieval in EDTA pH 8.0 for paraffin sections (datasheet M00215-1). The selected image used that retrieval, followed by 10% goat serum blocking and a 1:50 primary incubation overnight at 4°C (datasheet M00215-1). If staining is weak, check that sections were fully deparaffinised and compare retrieval heating and cooling across runs before changing conditions (standard IHC practice). If needed, test an alternative retrieval buffer on matched sections as a fallback, while retaining the EDTA condition as the reference (standard IHC practice). Judge improvement in expected neuropil or nerve-associated structures alongside negative controls, rather than by stronger staining alone (HPA tissue IHC; standard IHC practice).
How should I troubleshoot variable SNCA staining between differently fixed sections?
The selected SNCA tissue image identifies a paraffin section but does not state its fixative, so target-specific fixation sensitivity is unknown (datasheet M00215-1). Record fixative, fixation duration, tissue thickness and processing history for each specimen before comparing staining intensity (standard IHC practice). Process matched control tissue in each batch and apply the same EDTA pH 8.0 retrieval used for this antibody (datasheet M00215-1; standard IHC practice). Compare morphology and staining in expected structures, including cerebral cortex neuropil, rather than attributing every intensity difference to fixation (HPA tissue IHC; standard IHC practice). Optimise processing variables on matched sections if differences persist, and report them with the result (standard IHC practice).
Which SNCA staining patterns are plausible in a paraffin section?
Prioritise staining in neural processes and presynaptic regions: SNCA is highly expressed in central nervous system presynaptic terminals (UniProt P37840). High cerebral cortex neuropil staining and medium staining of cerebellar granular-layer processes provide tissue-level reference patterns (HPA tissue IHC). SNCA is also annotated in cytoplasm, membrane, nucleus, synapses, axons and secreted material, so compartment alone cannot establish specificity (UniProt P37840). It has no transmembrane segment, although membrane association is reported in dopaminergic neurons (UniProt P37840). Compare each pattern with local anatomy and a negative staining control; investigate diffuse signal that obscures structures before interpreting it (standard IHC practice).
Could the antibody epitope or SNCA processing explain discordant staining?
SNCA has three annotated isoform groups, labelled 1, 2–4 and 2–5; the supplied product caption does not map the antibody epitope (UniProt P37840; datasheet M00215-1). The record also lists N-terminal acetylation and phosphorylation at residues 87, 125 and 129 (UniProt P37840). Without epitope mapping, staining differences cannot be assigned to an isoform or modification, and the catalog antibody should not be treated as phospho-specific (UniProt P37840; datasheet M00215-1). Compare matched sections with an independently characterised antibody when epitope dependence matters (standard IHC practice). Report the antibody identity, retrieval condition and scoring compartment so readers can assess the scope of the result (standard IHC practice).
How can IF help resolve ambiguous SNCA staining seen by chromogenic IHC?
Use IF on matched material to ask whether SNCA signal overlaps a marker for the expected cell type, while keeping chromogenic IHC as the reference assay (standard IF practice). A neuronal marker is useful when assessing signal in presynaptic or axonal structures, which are annotated SNCA locations (UniProt P37840). Choose fluorophores in channels with low tissue autofluorescence and include single-channel and no-primary controls to detect bleed-through or background (standard IF practice). For an intracellular epitope, optimise permeabilisation; SNCA has no transmembrane segment, but the antibody's epitope side is not mapped in the supplied caption (UniProt P37840; datasheet M00215-1). Treat IF conditions as separately optimised because the supplied product evidence documents paraffin-section chromogenic IHC (datasheet M00215-1).
What controls distinguish diffuse SNCA signal from chromogenic background?
The selected paraffin-section image used 10% goat serum blocking, a 1:50 primary incubation overnight at 4°C, an enzyme-conjugated secondary and DAB development (datasheet M00215-1). Reproduce those documented conditions before adjusting primary concentration or incubation time on matched sections (datasheet M00215-1; standard IHC practice). Include a no-primary control and an appropriate peroxidase block to assess secondary-associated signal and endogenous enzyme activity (standard IHC practice). Examine section edges, folds and damaged areas separately because uneven reagent access can distort chromogenic staining (standard IHC practice). Preserve expected neuropil staining while reducing diffuse signal, using identically processed controls for comparison (HPA tissue IHC; standard IHC practice).
How should I quantify SNCA staining across tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the anatomical region and staining compartment before scoring, since SNCA is prominent in presynaptic structures and cerebral cortex neuropil (UniProt P37840; HPA tissue IHC). For cell-associated staining, record the percentage of positive cells and an intensity score, then calculate an H-score on the conventional 0–300 scale if appropriate (standard IHC practice). For process-rich regions, measure positive area or optical density per mm² within a predefined region instead of forcing a cell count (standard IHC practice). Normalise to sampled tissue area or the number of eligible cells, and keep acquisition, threshold and counterstain settings consistent (standard IHC practice). Report regional and compartment-specific results separately (standard IHC practice).
When is an apparent SNCA-positive cell or structure likely to be artefactual?
Interpret signal against anatomy: cerebral cortex neuropil and bone-marrow hematopoietic cells have high reported staining, whereas caudate glial cells are listed as not detected (HPA tissue IHC). SNCA can occupy cytoplasm, membrane, nucleus and axons, so an unexpected compartment needs corroboration rather than automatic rejection (UniProt P37840). Review serial morphology and a no-primary control when staining follows section edges, necrotic areas or regions with poor tissue preservation (standard IHC practice). Check endogenous peroxidase activity before assigning DAB deposits to SNCA, particularly when the staining pattern does not track intact cells or processes (standard IHC practice). In the selected glioma section, the caption establishes detection in tissue but does not identify the stained cell type (datasheet M00215-1).
Boster reagents
Best SNCA / Alpha-synuclein IHC Antibodies
Anti-SNCA IHC examples cover human glioma, colon cancer, brain and skin, plus mouse and rat brain (catalog IHC captions); IF/ICC is illustrated in SiHa cells (A00215-3 IF caption).
Real IHC data
Anti-Alpha Synuclein SNCA Rabbit Monoclonal Antibody
Cat # M00215-1
Real IHC data
Anti-Alpha Synuclein/SNCA Antibody ®
Cat # A00215-3
Real IHC data
Anti-SNCA Antibody (C-term)
Cat # M00215-2
M00215-1 shows paraffin-section IHC in human glioma and colon cancer and mouse brain (M00215-1 IHC captions); A00215-3 shows paraffin-section IHC in human, mouse and rat brain (A00215-3 IHC captions). M00215-2 shows IHC-P in formaldehyde-fixed human skin (M00215-2 IHC caption).
Which to pick: For tissue IHC, M00215-1 is a rabbit monoclonal option with human and mouse paraffin-section examples; the captions do not report the fixative (catalog: M00215-1 clone and IHC captions). For IF/ICC, choose A00215-3, which lists both applications and has a SiHa-cell IF example; it also has the broadest illustrated IHC species coverage, with human, mouse and rat brain examples whose fixative is unreported (catalog: A00215-3 applications, IF caption and IHC captions). For paraffin-section human skin IHC-P, choose M00215-2 (M00215-2 IHC caption). The selected M00215-1 tissue-IHC caption documents paraffin sections, but does not specify the fixative (selected-SKU IHC image M00215-1).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P37840 (SYUA_HUMAN, Alpha-synuclein).
- Human Protein Atlas. SNCA tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. SNCA subcellular location (ICC-IF): Highest expression in SK-MEL-30: 411.5 nTPM.
- Human Protein Atlas. SNCA antibody validation summary (2 antibodies).
- Polyethylenimine Nanoparticle-Mediated siRNA Delivery to Reduce α-Synuclein Expression in a Model of Parkinson's Disease. Molecular therapy. Nucleic acids 2017 — PMC5602522.
- Potentiation of neurotoxicity in double-mutant mice with Pink1 ablation and A53T-SNCA overexpression. Human molecular genetics 2015 — PMC4986551.
- Distinct clinical and neuropathological features of G51D SNCA mutation cases compared with SNCA duplication and H50Q mutation. Molecular neurodegeneration 2015 — PMC4549856.
- SNCA correlates with immune infiltration and serves as a prognostic biomarker in lung adenocarcinoma. BMC cancer 2022 — PMC9009002.
- PubMed PMID:8248242 — UniProt-cited evidence.
- PubMed PMID:7601450 — UniProt-cited evidence.
- PubMed PMID:7802671 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for SNCA (Alpha-synuclein). Expected localisation Presynaptic terminals; cytoplasm, membrane and nucleus (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet M00215-1). Validated IHC antibody: M00215-1 at 1:50 (the product's own IHC validation image is shown). Controls (HPA): positive Bone marrow (Hematopoietic cells); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human glioma tissue; fixative not specified (datasheet M00215-1); 2. Fixation: Image fixative and duration unreported (datasheet M00215-1); 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 M00215-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet M00215-1); 8. Primary antibody: Rabbit monoclonal (clone AGA-19) anti-SNCA, 1:50 (datasheet M00215-1); 9. Primary incubation: Overnight at 4 °C (datasheet M00215-1). Watch for: Fixation: Keep fixation consistent across sections (standard IHC practice; not target-specific); Caveat: Glia may be negative despite strong CNS neuropil staining (HPA tissue IHC); Isoform / epitope: Three isoforms; epitope coverage depends on antibody specificity (UniProt); Regulation: Enriched in brain and presynaptic terminals (UniProt). Evidence: UniProt P37840, HPA tissue IHC · Enhanced, HPA cell-line RNA · Highest expression in SK-MEL-30: 411.5 nTPM, Datasheet M00215-1, PMC4986551, PMC4549856. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/SNCA/immunohistochemistry-ihc-guide.