APLP2 / Amyloid beta precursor like protein 2 · IHC design guide

Design Immunohistochemistry for APLP2

Plan APLP2 IHC-P using granular cytoplasmic staining and high staining in adipocytes as tissue benchmarks (HPA tissue IHC). This guide pairs those benchmarks with the catalog antibody’s 2–5 μg/ml IHC range (datasheet A01232-1).

Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use

Immunohistochemistry protocol sheet for APLP2 (IHC for APLP2): expected localisation Granular cytoplasm (HPA tissue IHC); membrane and nucleus annotated (UniProt), antibody A01232-1, validated IHC image, and IHC protocol steps — Printable **APLP2** IHC protocol sheet — expected localisation Granular cytoplasm (HPA tissue IHC); membrane and nucleus annotated (UniProt), antibody A01232-1, controls and protocol steps. Open the full APLP2 IHC guide →

Navigate to: Protocols Staining pattern Controls Antibodies

APLP2 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	Granular cytoplasm (HPA tissue IHC); membrane and nucleus annotated (UniProt)
	Staining pattern	Granular cytoplasm in most tissues; high in adipocytes (HPA tissue IHC)
	Antigen retrieval	EDTA pH 8.0 HIER, heat-mediated (datasheet A01232-1)
	Positive control ⓘ	Adipose tissue+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	Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image A01232-1)
	Caveat	Staining and RNA show medium consistency (HPA tissue IHC)
	Regulation	Stimulus regulation unreported (UniProt)
	Isoform / epitope	6 isoforms; map the epitope to the extracellular or cytoplasmic region (UniProt)

Section 1

Recommended APLP2 IHC & IF Protocols

Compare the catalog antibody’s paraffin-section IHC protocol (datasheet A01232-1) with published retinal and tumor microarray staining protocols (PMC4897877; PMC4385836).

Recommended immunohistochemistry (IHC-P) protocol parameters
Sample	Paraffin-embedded human colorectal adenocarcinoma tissue; fixative not specified (datasheet A01232-1)
Fixation	Image fixative and duration unreported (datasheet A01232-1); 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 A01232-1); 20 min, 95–100 °C (standard)
Peroxidase block	3% H2O2, 10 min, room temperature (standard)
Blocking	10% goat serum (datasheet A01232-1)
Primary antibody	Rabbit anti-APLP2, 2-5 μg/ml (datasheet A01232-1)
Primary incubation	Overnight at 4 °C (datasheet A01232-1)
Detection	HRP-conjugated secondary, DAB chromogen (datasheet A01232-1)
Counterstain	Hematoxylin, blue, dehydrate and mount (standard)
Expected result	APLP2-positive staining in adipocytes of adipose tissue (HPA tissue IHC: High). HPA tissue profile: Granular cytoplasmic expression in most tissues. No signal in the no-primary control.

💡Decision noteStart with heat-mediated EDTA pH 8.0 retrieval for the catalog antibody (datasheet A01232-1). For human tumor microarrays, citrate pH 6.8 is published (PMC4385836).

Section 2

What Is the Expected APLP2 Staining Pattern?

APLP2 should most often appear as granular cytoplasmic staining in tissue IHC (HPA: tissue profile). Strong staining is reported in adipocytes, respiratory epithelial cells, neuronal cells, and several glandular and hematopoietic cell populations (HPA: High in listed cells). APLP2 also has a cell membrane location and one transmembrane segment (UniProt Q06481: subcellular location and topology). HPA rates the tissue profile Approved, with medium consistency between staining and RNA data (HPA: reliability).

What am I looking at on my slide?
Granular cytoplasmic staining in the expected cells, with stronger signal in a listed high-staining population.	This fits the reported tissue IHC profile (HPA: granular cytoplasmic expression; High in listed cells). Judge the pattern within the relevant cell population rather than requiring every cell in a section to stain equally.
Predominantly membrane or nuclear staining, with little granular cytoplasmic signal.	This differs from the usual tissue IHC profile (HPA: granular cytoplasmic expression). Membrane and nucleus are reported APLP2 locations (UniProt Q06481: subcellular location), so treat the finding as uncertain and check controls before calling it an artefact.
Strong staining in a cell population expected to show low signal, such as cholangiocytes or ovarian stroma cells.	These populations are listed as Low, rather than negative (HPA: Liver cholangiocytes Low; Ovary ovarian stroma cells Low). Disproportionately strong signal warrants review for cross-reactivity or endogenous detection activity; it does not establish either cause.
Broad, diffuse chromogen deposits obscure cell borders or tissue structure.	A diffuse deposit cannot be scored confidently against the reported granular cytoplasmic pattern (HPA: tissue profile). In general IHC practice, inspect background controls and the detection workflow before assigning that signal to APLP2.
No convincing signal in a tissue containing a listed high-staining cell population.	Check that the relevant cells are present: HPA reports High staining in bronchial respiratory epithelial cells, adipocytes, and caudate neuronal cells, among others (HPA: tissue IHC). A blank result in those cells calls for assay troubleshooting, not an immediate biological negative.

💡Expected APLP2 appearanceCall a positive result when the relevant cells show convincing granular cytoplasmic chromogen, particularly in an HPA High population; diffuse background or unexpectedly strong staining in HPA Low cells is suspect (HPA: tissue IHC profile and levels).

How each factor affects the staining
Cell compartment and epitope location	APLP2 has an extracellular region at residues 32–692 and a cytoplasmic region at 717–763 (UniProt Q06481: topology). Antibody epitope location is not supplied, so the record cannot predict whether this reagent favors either region.
Tissue and cell population	The HPA tissue profile is broad, with low RNA tissue specificity, but named populations span High and Low IHC staining (HPA: RNA specificity; tissue IHC). Select and score a documented cell population within each section.
Antibody evidence	The listed antibody, HPA039319, is Approved for IHC and ICC (HPA: antibody validation). The tissue profile has medium staining–RNA consistency (HPA: reliability); these ratings do not establish identical performance in every specimen.
Isoforms and soluble APLP2	Six isoforms are listed, and a soluble form is described (UniProt Q06481: isoforms and function). Without an antibody epitope or specimen-specific evidence, this record cannot assign an IHC pattern to a particular isoform or soluble product.
IF/ICC Q&A: where is APLP2 seen?	The separate ICC-IF evidence reports approved Golgi apparatus and vesicle locations (HPA: subcellular summary). That observation informs IF interpretation; the paraffin-section decision here follows the granular cytoplasmic tissue IHC profile (HPA: tissue profile).

Why is my staining missing, weak or wrong?
Situation	Likely cause	Next action
A documented high-staining cell population has no visible chromogen.	The result conflicts with the listed High IHC observation, though HPA reports only medium staining–RNA consistency (HPA: tissue IHC; reliability).	Confirm the cells are present, then review the IHC-validated antibody's documented dilution, retrieval, detection, and positive-control performance. Retrieval review is general IHC troubleshooting, not a reported APLP2 fixation effect.
Chromogen covers much of the section without a readable cellular pattern.	The result cannot be matched to granular cytoplasmic expression (HPA: tissue profile). Background can also arise from general IHC detection steps.	Compare negative detection controls and inspect blocking, washes, and chromogen development under the laboratory's standard IHC workflow; score only signal that remains cell-associated.
Cholangiocytes or ovarian stroma cells stain as strongly as the chosen high-staining reference cells.	Those populations are listed as Low (HPA: tissue IHC), so consider cross-reactivity or endogenous detection activity as possible explanations.	Compare matched controls and cell populations on the same run. Check endogenous enzyme blocking when relevant to the chromogen system; do not label these Low populations as biological negatives.
A section shows mainly nuclear or surface signal.	This departs from the usual granular cytoplasmic tissue IHC profile (HPA: tissue profile), although nucleus and cell membrane are reported locations (UniProt Q06481: subcellular location).	Review morphology, control staining, and the antibody's documented target region if available. Describe the observed compartment without calling it specific solely from topology.
Signal differs sharply between two tissues or between cell populations in one tissue.	HPA reports broad expression with distinct High and Low cell-level IHC observations (HPA: RNA specificity; tissue IHC).	Identify the cells being compared and score each population separately. Use the reported level for that population as context rather than treating a whole tissue as uniformly positive.
ICC-IF shows punctate signal that seems unlike the paraffin IHC result.	Golgi apparatus and vesicles are approved ICC-IF locations, while tissue IHC is described as granular cytoplasmic (HPA: subcellular summary; tissue profile).	Interpret each result against its application-specific HPA pattern. Use the separate IF/ICC guide for imaging decisions; this IHC section does not supply an IF protocol.

Source: UniProt Q06481 Human Protein Atlas tissue Human Protein Atlas subcellular

Experiment evidence

IHC & IF images showing APLP2 staining

IHC analysis of APLP2 using anti-APLP2 antibody (A01232-1). APLP2 was detected in a paraffin-embedded section of human colorectal adenocarcinoma tissue. Heat mediated antigen retrieval was performed in EDTA buffer (pH 8.0, epitope retrieval solution). The tissue section was blocked with 10% goat serum. The tissue section was then incubated with 2 μg/ml rabbit anti-APLP2 Antibody (A01232-1) overnight at 4°C. Peroxidase Conjugated Goat Anti-rabbit IgG was used as secondary antibody and incubated for 30 minutes at 37°C. The tissue section was developed using HRP Conjugated Rabbit IgG Super Vision Assay Kit (Catalog # SV0002) with DAB as the chromogen.

A01232-1 · IHCIHC analysis of APLP2 using anti-APLP2 antibody (A01232-1). APLP2 was detected in a paraffin-embedded section of human colorectal adenocarci

IHC analysis of APLP2 using anti-APLP2 antibody (A01232-1). APLP2 was detected in a paraffin-embedded section of human liver cancer tissue. Heat mediated antigen retrieval was performed in EDTA buffer (pH 8.0, epitope retrieval solution). The tissue section was blocked with 10% goat serum. The tissue section was then incubated with 2 μg/ml rabbit anti-APLP2 Antibody (A01232-1) overnight at 4°C. Peroxidase Conjugated Goat Anti-rabbit IgG was used as secondary antibody and incubated for 30 minutes at 37°C. The tissue section was developed using HRP Conjugated Rabbit IgG Super Vision Assay Kit (Catalog # SV0002) with DAB as the chromogen.

A01232-1 · IHCIHC analysis of APLP2 using anti-APLP2 antibody (A01232-1). APLP2 was detected in a paraffin-embedded section of human liver cancer tissue.

IF analysis of APLP2 using anti-APLP2 antibody (A01232-1). APLP2 was detected in an immunocytochemical section of HELA cells. Enzyme antigen retrieval was performed using IHC enzyme antigen retrieval reagent (AR0022) for 15 mins. The cells were blocked with 10% goat serum. And then incubated with 5 μg/mL rabbit anti-APLP2 Antibody (A01232-1) overnight at 4°C. Cy3 Conjugated Goat Anti-Rabbit IgG (BA1032) was used as secondary antibody at 1:500 dilution and incubated for 30 minutes at 37°C. The section was counterstained with DAPI. Visualize using a fluorescence microscope and filter sets appropriate for the label used.

A01232-1 · IFIF analysis of APLP2 using anti-APLP2 antibody (A01232-1). APLP2 was detected in an immunocytochemical section of HELA cells. Enzyme antigen

HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000084234-APLP2/tissue/cerebral+cortex#imid_9950984

HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000084234-APLP2/tissue/colon#imid_9950910

HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000084234-APLP2/tissue/liver#imid_9950911

HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000084234-APLP2/tissue/kidney#imid_9950912

HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA039319; green = APLP2, blue = nucleus, red = microtubules.

← swipe / scroll for more images →

Real IHC / IF data behind the staining-pattern expectations in this section.

Sample controls for APLP2 IHC & IF

🧪Run adipose tissue first and look for staining in adipocytes (HPA: High in adipocytes). HPA detects APLP2 in all 45 scored tissues, so there is no validated negative tissue; use no-primary and isotype controls, and treat any unstained non-adipocyte profiles on the positive slide as background comparisons rather than proven negative cells (HPA: no negative rows).

Positive control tissue: Adipose tissue (Adipocytes, HPA High)

Negative control tissue: None in HPA: APLP2 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 APLP2 in A-431, U-251MG, U2OS, with annotated localisation: Golgi apparatus (approved), Vesicles (approved) (HPA subcellular).

Technical controls: Include a no-primary, secondary-only slide, a rabbit IgG isotype control matched to the primary antibody’s clonality, and an APLP2 knockout specimen processed in parallel if available (caption: rabbit primary). Quench endogenous peroxidase before HRP/DAB detection, particularly around blood-containing vessels in adipose tissue (caption: HRP/DAB detection).

⚠️Feasibility: No APLP2-specific fixation window or fixation effect is reported in the supplied evidence, and the selected A01232-1 paraffin-section caption does not state a fixative (caption: fixative unreported). Heat-mediated retrieval in EDTA at pH 8.0 is a documented IHC starting condition, but retrieval dependency and whether frozen sections or IF are easier are unreported (caption: EDTA retrieval). In paraffin adipose sections, extracted lipid leaves clear adipocyte vacuoles, so assess staining at the cell rim rather than in the vacuole (standard IHC practice).

HPA tissue IHC evidence for APLP2

Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Approved — 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
Adipose tissue	Adipocytes	High	Protein (IHC)	HPA →
Adrenal gland	Glandular cells	High	Protein (IHC)	HPA →
Appendix	Glandular cells	High	Protein (IHC)	HPA →
Bone marrow	Hematopoietic cells	High	Protein (IHC)	HPA →
Breast	Adipocytes	High	Protein (IHC)	HPA →

Undetected expression · recommended negative controls

Tissue	Cell type	Level	Evidence	Source
None in HPA: APLP2 is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead.

Section 3

Advanced APLP2 IHC Tips

Troubleshoot APLP2 staining in paraffin sections by checking retrieval, tissue preparation, expected localisation and controls before interpreting chromogenic signal.

How should I retrieve APLP2 in paraffin sections when staining is weak?

Begin with heat mediated antigen retrieval in EDTA pH 8.0 for paraffin sections (datasheet A01232-1). The selected APLP2 image used this retrieval before incubation with 2 μg/ml primary antibody overnight at 4°C (caption A01232-1). Keep section thickness, heating, cooling and detection conditions consistent when comparing retrieval runs (standard IHC practice). If staining remains weak, adjust heating duration in small increments while checking tissue integrity and a no-primary control (standard IHC practice). Record whether any gain occurs in the expected granular cytoplasmic pattern rather than as uniform tissue staining (HPA: tissue IHC profile; standard IHC practice).

Could fixation explain variable APLP2 staining across paraffin blocks?

Target-specific fixation sensitivity for APLP2 is unknown from the supplied evidence (caption A01232-1: fixative not stated). The selected image identifies a paraffin section of human colorectal adenocarcinoma, but gives no fixative or fixation duration (caption A01232-1). Compare blocks with documented processing histories using the same EDTA pH 8.0 retrieval and primary antibody conditions (datasheet A01232-1; standard IHC practice). Include a consistently processed positive control section in each run to separate block variation from staining-run variation (standard IHC practice). If a block fails, assess morphology and control staining before attributing the result to APLP2 loss (standard IHC practice).

Which staining compartments are plausible for APLP2 in tissue sections?

Expect predominantly granular cytoplasmic staining across many tissues in the supplied tissue IHC profile (HPA: tissue IHC profile). Golgi apparatus and vesicles are approved subcellular locations in the separate cell imaging evidence (HPA: subcellular localisation). Cell membrane and nucleus are also recorded locations, so a sharply defined signal there warrants evaluation rather than automatic rejection (UniProt Q06481: subcellular location). APLP2 has an extracellular region at residues 32–692, one transmembrane segment at 693–716, and a cytoplasmic region at 717–763 (UniProt Q06481: topology). Score compartments separately and compare each with matched controls and preserved tissue morphology (standard IHC practice).

How can isoforms or epitope position change the APLP2 IHC readout?

APLP2 has 6 recorded isoforms, so check the antibody's stated immunogen before assuming that all variants are detected (UniProt Q06481: isoforms; standard IHC practice). Its extracellular region spans residues 32–692, while residues 717–763 lie on the cytoplasmic side (UniProt Q06481: topology). A glycosylation site at residue 626 and a reported phosphoserine at 590 make epitope mapping relevant to interpretation (UniProt Q06481: modifications). The supplied caption does not identify the antibody epitope, so these features alone cannot establish which molecular forms it recognises (caption A01232-1). Compare staining patterns with an independently mapped antibody when isoform or cleavage specificity matters (standard IHC practice).

How should I investigate an unexpected APLP2 pattern by immunofluorescence?

Use IF as a separate localisation check when granular cytoplasmic chromogenic staining is difficult to assign to a cell population (HPA: tissue IHC profile; standard IF practice). In bronchial material, multiplex with a respiratory epithelial cell marker to identify the expected cell population (HPA: high in bronchus respiratory epithelial cells; standard IF practice). Choose a far-red fluorophore and inspect an unstained section in that channel to assess tissue autofluorescence (standard IF practice). Match permeabilisation to the mapped epitope: intracellular epitopes require access across membranes, whereas surface-facing epitopes can be assessed without that step (UniProt Q06481: topology; standard IF practice). Compare the result with the reported Golgi and vesicle localisation (HPA: subcellular localisation).

What should I check when DAB staining obscures APLP2 signal?

The selected image used 10% goat serum blocking, a goat anti-rabbit peroxidase secondary antibody and DAB development (caption A01232-1). Include a no-primary section to reveal secondary reagent binding and endogenous peroxidase signal (standard IHC practice). Apply a peroxidase block before chromogenic detection, then check whether background persists in the no-primary section (standard IHC practice). If diffuse colour remains, review blocking, washes, primary concentration and DAB development while keeping the positive control in the same run (standard IHC practice). Judge improvements by preservation of the expected granular cytoplasmic signal, not simply by lower overall colour (HPA: tissue IHC profile; standard IHC practice).

How should I score APLP2 staining across comparable paraffin sections? ⚠ ANSWER MARKED FOR VERIFICATION

Define the tissue compartment and eligible viable cells before scoring, and exclude folds, torn edges and necrotic areas (standard IHC practice). Report the percentage of positive cells and staining intensity separately, or calculate an H-score from intensity grades 0–3 across cells, yielding 0–300 (standard IHC practice). For spatial comparisons, report positive-cell density per mm² of viable tissue within the same defined compartment (standard IHC practice). Normalise cell counts to all eligible cells and area measurements to viable compartment area, using fixed thresholds across slides (standard IHC practice). Record granular cytoplasmic and other compartment scores separately because the reference IHC pattern is granular cytoplasmic (HPA: tissue IHC profile).

When is an apparent APLP2 positive result likely to be artefactual?

A convincing result should reproduce a cellular pattern and persist under consistent staining conditions alongside an appropriate positive control (standard IHC practice). Granular cytoplasmic staining accords with the tissue IHC profile; IF evidence also places APLP2 in Golgi apparatus and vesicles (HPA: tissue IHC profile; HPA: subcellular localisation). Diffuse colour confined to section edges, folds or necrosis needs comparison with intact tissue and a no-primary section (standard IHC practice). Likewise, signal in an unexpected cell population or compartment requires independent confirmation rather than immediate biological interpretation (standard IHC practice). Check endogenous peroxidase with a no-primary control before calling DAB deposition APLP2 positive (standard IHC practice).

Boster reagents

Best APLP2 / Amyloid beta precursor like protein 2 IHC Antibodies

A01232-1 has paraffin-section IHC images from human tumors and an IF/ICC image from HeLa cells (catalog image captions). Both antibodies list Human, Mouse and Rat reactivity for IHC (catalog applications and reactivity).

Real IHC data

Anti-APLP2 Antibody ®

Cat # A01232-1

View product →

A01232-1 has IHC images from paraffin sections of human colorectal adenocarcinoma, liver cancer, lung cancer and testicular germ cell tumors, plus an IF/ICC image from HeLa cells (catalog image captions). M01232 is listed for IHC in Human, Mouse and Rat, but has no supplied IHC or IF image (catalog applications, reactivity and image fields).

Which to pick: Choose A01232-1 for tissue IHC when an illustrated paraffin-section workflow is useful: its IHC captions report EDTA retrieval at pH 8.0, 2 μg/ml primary antibody and DAB detection; the fixative is unreported (A01232-1 IHC image captions). Choose A01232-1 for IF/ICC because it lists both applications and has a HeLa cell IF image; M01232 is a rabbit monoclonal listed for IHC, with no IF/ICC application or image supplied (catalog applications, clone and image fields). For cross-species IHC, both list Human, Mouse and Rat reactivity, while the supplied tissue images document Human samples only for A01232-1 (catalog reactivity and IHC image captions).

Each figure is that product's own IHC / IF validation image from its datasheet.

References

UniProt Consortium. UniProt entry Q06481 (APLP2_HUMAN, Amyloid beta precursor like protein 2).
Human Protein Atlas. APLP2 tissue IHC expression (reliability: Approved).
Human Protein Atlas. APLP2 subcellular location (ICC-IF): Localized to the Golgi apparatus and vesicles..
Human Protein Atlas. APLP2 antibody validation summary (1 antibodies).
Amyloid Precursor-like Protein 2 Expression Increases during Pancreatic Cancer Development and Shortens the Survival of a Spontaneous Mouse Model of Pancreatic Cancer. Cancers 2021 — PMC8036577.
Amyloid Precursor-Like Protein 2 deletion-induced retinal synaptopathy related to congenital stationary night blindness: structural, functional and molecular characteristics. Molecular brain 2016 — PMC4897877.
APLP2 Regulates Refractive Error and Myopia Development in Mice and Humans. PLoS genetics 2015 — PMC4551475.
Amyloid precursor-like protein 2 (APLP2) affects the actin cytoskeleton and increases pancreatic cancer growth and metastasis. Oncotarget 2015 — PMC4385836.
PubMed PMID:8485127 — UniProt-cited evidence.
PubMed PMID:8220435 — UniProt-cited evidence.
PubMed PMID:7702756 — UniProt-cited evidence.