SLC38A2 / Sodium-coupled neutral amino acid symporter 2 · IHC design guide

Design Immunohistochemistry for SLC38A2

Plan paraffin-section IHC for SLC38A2 using the reported cytoplasmic tissue pattern and high staining in kidney tubular cells (HPA tissue IHC). Interpret staining alongside its annotated plasma membrane location and insulin-dependent recruitment (UniProt).

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

Immunohistochemistry protocol sheet for SLC38A2 (IHC for SLC38A2): expected localisation Cytoplasmic tissue staining; plasma membrane localization is expected from protein annotation (HPA tissue IHC; UniProt), antibody A03242-1, validated IHC image, and IHC protocol steps — Printable **SLC38A2** IHC protocol sheet — expected localisation Cytoplasmic tissue staining; plasma membrane localization is expected from protein annotation (HPA tissue IHC; UniProt), antibody A03242-1, controls and protocol steps. Open the full SLC38A2 IHC guide →

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SLC38A2 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 tissue staining; plasma membrane localization is expected from protein annotation (HPA tissue IHC; UniProt)
	Staining pattern	Cytoplasmic staining in most tissues, including glandular cells (HPA tissue IHC)
	Antigen retrieval	Tris-EDTA pH 9.0 HIER, heat-mediated (datasheet A03242-1)
	Positive control ⓘ	Duodenum+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 consistent across sections (standard IHC practice; not target-specific)
	Caveat	Antibody staining has low consistency with RNA expression (HPA tissue IHC)
	Regulation	Insulin promotes recruitment to the plasma membrane (UniProt)
	Isoform / epitope	2 isoforms; epitope coverage is unknown, and cytoplasmic versus extracellular location matters (UniProt)

Section 1

Recommended SLC38A2 IHC & IF Protocols

The catalog antibody’s IHC-P protocol is accompanied by two published chromogenic SLC38A2 IHC protocols (PMC7334074; PMC11876615).

Recommended immunohistochemistry (IHC-P) protocol parameters
Sample	Paraffin-embedded human Colon cancer tissue; fixative not specified (datasheet A03242-1)
Fixation	Image fixative and duration unreported (datasheet A03242-1); verify before use.
Sectioning	4–5 µm sections on charged slides (standard)
Deparaffinisation	Xylene, graded ethanol series to water (standard)
Antigen retrieval	Heat retrieval: Tris-EDTA pH 9.0 (datasheet A03242-1); 20 min, 95–100 °C (standard)
Peroxidase block	3% H2O2, 10 min, room temperature (standard)
Blocking	10% normal serum of the secondary host, 30 min, room temperature (standard)
Primary antibody	Rabbit anti-SLC38A2, 1:50 recommended; image 1:200 (datasheet A03242-1)
Primary incubation	Overnight at 4 °C (standard)
Detection	HRP-polymer secondary, DAB chromogen 5–10 min (standard)
Counterstain	Hematoxylin, blue, dehydrate and mount (standard)
Expected result	SLC38A2-positive staining in glandular cells of duodenum (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression in most tissues. No signal in the no-primary control.

💡Decision noteStart with heat-mediated Tris-EDTA, pH 9.0 (datasheet A03242-1); both published protocols use citrate, pH 6.0, as an alternative (PMC7334074; PMC11876615).

Section 2

What Is the Expected SLC38A2 Staining Pattern?

SLC38A2 is an 11-pass membrane transporter that can move between intracellular pools and the plasma membrane (UniProt Q96QD8 topology and subcellular location). In paraffin-section IHC, expect mainly cytoplasmic staining in many tissues, including strong staining in kidney tubule cells and duodenal glandular cells (HPA tissue IHC). HPA rates the tissue staining Approved but reports low consistency with RNA expression (HPA tissue IHC reliability).

What am I looking at on my slide?
Strong cytoplasmic staining in kidney tubule cells or duodenal glandular cells, with possible membrane emphasis.	This fits HPA's High IHC staining in those cells and its broader cytoplasmic tissue profile (HPA tissue IHC). Membrane emphasis is biologically plausible given the cell membrane location, but HPA does not require a crisp membrane outline in paraffin sections (UniProt Q96QD8 subcellular location; HPA tissue IHC).
Predominantly nuclear staining, especially when cytoplasmic staining is absent.	A nuclear-only pattern conflicts with the reported cell membrane location and HPA's cytoplasmic IHC profile (UniProt Q96QD8 subcellular location; HPA tissue IHC). Treat it as suspect staining; review controls and detection conditions before assigning it to SLC38A2 (standard IHC practice).
Strong signal in adipocytes, marrow hematopoietic cells, or skeletal myocytes.	HPA reports SLC38A2 as not detected in these specific cell populations (HPA tissue IHC). Check whether the signal follows tissue pigment, endogenous detection activity, or another antibody target; these HPA observations do not prove absolute absence under every condition (HPA tissue IHC; standard IHC practice).
A uniform haze covers positive cells, negative cells, and surrounding tissue.	Diffuse staining that ignores cell boundaries is hard to reconcile with the reported cell associated distribution (HPA tissue IHC; UniProt Q96QD8 subcellular location). It can reflect excess detection background or inadequate blocking or washing; compare a no-primary control and adjust the general IHC workflow (standard IHC practice).
No signal in kidney tubule cells or duodenal glandular cells.	Target-specific fixation effects are not established by the supplied assay evidence. Verify with a matched IHC source before attributing a result to fixation.

💡Expected SLC38A2 appearanceCall the IHC result supportive when cytoplasmic staining, sometimes with membrane emphasis, is strong in kidney tubule or duodenal glandular cells; nuclear-only or uniform tissue-wide staining is suspect (HPA tissue IHC: High in both cell populations and cytoplasmic profile; UniProt Q96QD8 subcellular location; standard IHC practice).

How each factor affects the staining
Cellular location	UniProt places SLC38A2 at the cell membrane and notes recruitment from trans-Golgi or endosomal pools after insulin stimulation (UniProt Q96QD8 subcellular location). HPA describes predominantly cytoplasmic tissue IHC, so a cytoplasmic component is compatible with the observed slide profile; neither source sets a required membrane-to-cytoplasm ratio for paraffin IHC (HPA tissue IHC; UniProt Q96QD8).
Tissue and cell selection	HPA lists High staining in kidney tubule cells, duodenal and small-intestinal glandular cells, oral squamous epithelial cells, pancreatic exocrine cells, and testicular peritubular cells (HPA tissue IHC). Its not detected calls apply to specified cells, including adipocytes and skeletal myocytes, rather than every cell in those tissues (HPA tissue IHC).
Validation strength	The tissue IHC reliability is Approved, with low consistency between antibody staining and RNA expression (HPA tissue IHC reliability). HPA035180 is Approved for IHC, while HPA069672 is Supported for ICC; those ratings apply to different antibodies and applications (HPA antibodies). Interpret a novel cell pattern alongside controls rather than assuming it is independently confirmed (standard IHC practice).
Topology and epitope	The protein has 11 transmembrane segments and both cytoplasmic and extracellular regions (UniProt Q96QD8 topology). The supplied record does not locate this antibody's epitope, so topology alone cannot specify an antigen retrieval setting, predict epitope exposure, or explain a missing IHC signal (UniProt Q96QD8 topology; supplied antibody record).
Isoforms and processing	UniProt lists 2 isoforms, no signal peptide or propeptide, and one annotated chain spanning residues 1–506 (UniProt Q96QD8 isoforms and processing). Without an antibody epitope or isoform-specific validation in the supplied evidence, do not assign differing staining patterns to an isoform or to cleavage (UniProt Q96QD8; supplied antibody record).
Does IF/ICC show the same pattern?	HPA reports a supported plasma membrane location in ICC-IF, using an antibody with Supported ICC status (HPA subcellular; HPA antibodies: HPA069672). This supports membrane localization but does not replace the cytoplasmic paraffin IHC profile or establish an IF/ICC protocol here (HPA subcellular; HPA tissue IHC).

Why is my staining missing, weak or wrong?
Situation	Likely cause	Next action
Positive comparator is blank.	Kidney tubule and duodenal glandular cells are rated High by HPA; a blank slide may indicate a workflow or detection failure (HPA tissue IHC; standard IHC practice).	Confirm the comparator cells are present, then review the catalog antibody's IHC-P instructions, dilution, retrieval, and detection controls (standard IHC practice). Do not infer a target-specific fixation effect from this result (HPA tissue IHC).
Staining is nuclear-only.	This conflicts with the reported membrane location and cytoplasmic tissue IHC profile (UniProt Q96QD8 subcellular location; HPA tissue IHC).	Compare the no-primary control and a HPA High cell population; review blocking, antibody concentration, and detection background before scoring nuclear signal as specific (HPA tissue IHC; standard IHC practice).
Adipocytes or skeletal myocytes stain strongly.	HPA calls these cell types not detected; cross-reactivity or endogenous detection activity is possible (HPA tissue IHC; standard IHC practice).	Check cell identity and no-primary controls, then compare staining with a HPA High population on the same run (HPA tissue IHC; standard IHC practice).
The whole section has a brown haze.	Uniform background can arise from detection chemistry, incomplete blocking, or insufficient washing (standard chromogenic IHC practice).	Review no-primary and detection-only controls; optimize blocking, washing, and antibody dilution using the catalog IHC-P instructions (standard IHC practice).
Signal is cytoplasmic without a sharp membrane rim.	HPA describes cytoplasmic expression in most tissues, while UniProt reports intracellular pools as well as cell membrane location (HPA tissue IHC; UniProt Q96QD8 subcellular location).	Score cell type and background first; do not reject an otherwise matching IHC pattern solely because the membrane edge is indistinct (HPA tissue IHC; standard IHC interpretation).
IHC and ICC-IF images look different.	HPA reports cytoplasmic tissue IHC and supported plasma membrane ICC-IF; its listed IHC and ICC antibodies also have different application ratings (HPA tissue IHC; HPA subcellular; HPA antibodies).	Interpret each result within its own application and antibody validation, then compare controls and cell identity before calling the patterns contradictory (HPA antibodies; standard IHC/ICC interpretation).

Source: UniProt Q96QD8 Human Protein Atlas tissue Human Protein Atlas subcellular

Experiment evidence

IHC & IF images showing SLC38A2 staining

Immunohistochemical analysis of paraffin-embedded human Colon cancer. 1, Antibody was diluted at 1:200(4° overnight). 2, Tris-EDTA,pH9.0 was used for antigen retrieval. 3,Secondary antibody was diluted at 1:200(room temperature, 45min).

A03242-1 · IHCImmunohistochemical analysis of paraffin-embedded human Colon cancer. 1, Antibody was diluted at 1:200(4° overnight). 2, Tris-EDTA,pH9.0 was

HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000134294-SLC38A2/tissue/cerebral+cortex#imid_8829547

HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000134294-SLC38A2/tissue/colon#imid_8824081

HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000134294-SLC38A2/tissue/liver#imid_8824082

HPA · PancreasHuman Protein Atlas IHC, Pancreas. Source: https://www.proteinatlas.org/ENSG00000134294-SLC38A2/tissue/pancreas#imid_8824017

HPA ICC-IF BJ [Human fibroblast] — SLC38A2 (HPA069672)

HPA · ICC-IF BJ [Human fibroblast]Human Protein Atlas immunofluorescence, BJ [Human fibroblast], antibody HPA069672; green = SLC38A2, blue = nucleus, red = microtubules.

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

Sample controls for SLC38A2 IHC & IF

🧪Run duodenum first: glandular cells should stain (HPA: High in duodenal glandular cells). Use skeletal muscle myocytes as the negative tissue (HPA: Not detected in skeletal muscle myocytes); on the duodenum slide, assess non-glandular cells for background staining without assuming they are target-negative.

Positive control tissue: Duodenum (Glandular cells, HPA High)

Negative control tissue: Adipose tissue (HPA Not detected)

ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show SLC38A2 in BJ [Human fibroblast], EFO-21, U2OS, RPTEC/TERT1, hTERT-RPE1 (serum starved), with annotated localisation: Plasma membrane (supported) (HPA subcellular).

Technical controls: Include no-primary (secondary-only) and host-species-matched antibody controls: an isotype control for a monoclonal primary or normal IgG for a polyclonal primary (standard IHC practice). Use SLC38A2 knockout tissue as a biological negative if available, and control for endogenous peroxidase and biotin in duodenum before interpreting chromogenic signal (standard IHC practice).

⚠️Feasibility: A target-specific fixation window or fixation effect is unreported in the supplied evidence, and the selected A03242-1 tissue-IHC caption does not state a fixative (caption: fixative unreported). The caption reports Tris-EDTA at pH 9.0 for antigen retrieval and a 1:200 primary dilution in a paraffin-section example; retrieval performance in duodenum remains unreported (caption: colon cancer example). Frozen-section feasibility is unreported; IF/ICC may help assess membrane localisation (HPA subcellular: plasma membrane supported), while endogenous peroxidase and biotin can complicate duodenal chromogenic staining (standard IHC practice).

HPA tissue IHC evidence for SLC38A2

Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Approved — Low 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
Duodenum	Glandular cells	High	Protein (IHC)	HPA →
Kidney	Cells in tubules	High	Protein (IHC)	HPA →
Oral mucosa	Squamous epithelial cells	High	Protein (IHC)	HPA →
Pancreas	Exocrine glandular cells	High	Protein (IHC)	HPA →
Small intestine	Glandular cells	High	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 →
Esophagus	Squamous epithelial cells	Not detected	Protein (IHC)	HPA →
Ovary	Ovarian stroma cells	Not detected	Protein (IHC)	HPA →
Skeletal muscle	Myocytes	Not detected	Protein (IHC)	HPA →

Section 3

Advanced SLC38A2 IHC Tips

Troubleshoot SLC38A2 staining by checking retrieval, tissue processing, membrane localisation, controls, and scoring before interpreting chromogenic signal.

How should I adjust retrieval when SLC38A2 staining is weak or patchy?

Start with heat-mediated Tris-EDTA retrieval at pH 9.0 for the paraffin-section IHC assay (datasheet A03242-1). Keep section thickness, heating time, cooling, and detection conditions constant while comparing retrieval runs (general IHC practice). The documented human colon cancer image used primary antibody at 1:200 overnight at 4 °C; use that as the product-specific starting condition when assessing weak signal (datasheet A03242-1). If staining remains weak, compare a milder retrieval condition on serial sections, but treat any alternative buffer or pH as an optimisation experiment rather than a documented product condition (general IHC practice). Score signal and tissue preservation together, especially along section edges (general IHC practice).

Could fixation explain weak SLC38A2 staining in my paraffin sections?

Target-specific fixation sensitivity is unknown: the selected tissue-IHC caption identifies paraffin-embedded human colon cancer but does not state the fixative (datasheet A03242-1). Record the fixative, fixation duration, processing history, and section age for each case before comparing staining (general IHC practice). Run similarly processed reference sections in the same batch and keep retrieval and detection settings constant when investigating a suspected fixation effect (general IHC practice). If a specimen stains poorly, compare it with another processing batch only after checking section integrity and the control reaction; a difference alone cannot establish fixation sensitivity for SLC38A2 (general IHC practice). Do not assign a target-specific fixation threshold without matched evidence.

Should convincing SLC38A2 IHC appear at the membrane or in the cytoplasm?

Assess membrane-associated staining and cytoplasmic staining separately: SLC38A2 is assigned to the cell membrane, while insulin can recruit it from a trans-Golgi or endosomal pool (UniProt Q96QD8 subcellular). Tissue IHC shows cytoplasmic expression in most tissues, whereas cell imaging supports plasma-membrane localisation (HPA tissue IHC; HPA subcellular). On chromogenic sections, examine whether a membrane rim follows intact cell borders and whether diffuse cytoplasmic colour persists in matched controls (general IHC practice). Record both compartments rather than treating cytoplasmic signal as automatically false or membrane signal as sufficient proof of specificity (UniProt Q96QD8 subcellular; HPA tissue IHC). Interpret compartment shifts only alongside specimen context and assay controls.

Can the antibody distinguish SLC38A2 isoforms or reveal which side carries its epitope?

SLC38A2 has 2 annotated isoforms, but the supplied antibody caption does not identify its epitope or establish isoform selectivity (UniProt Q96QD8 isoforms; datasheet A03242-1). The protein has 11 transmembrane segments, with cytoplasmic and extracellular loops, so access to a particular epitope depends on its mapped sequence and section processing (UniProt Q96QD8 topology; general IHC practice). Check the antibody's immunogen coordinates against the isoform sequences before claiming isoform coverage or a membrane-side assignment (general IHC practice). Glycosylation is annotated at residues 258 and 274, but its effect on this antibody's IHC signal is unreported (UniProt Q96QD8 glycosylation; datasheet A03242-1). Report staining as SLC38A2 immunoreactivity unless isoform-specific validation is available.

How can I cross-check the chromogenic IHC pattern using multiplex IF?

Use IF as a separate cross-check of the chromogenic pattern, since the selected product caption documents paraffin-section IHC conditions and supplies no IF procedure (datasheet A03242-1). Pair SLC38A2 with a validated marker for the cell population being examined; glandular cells in duodenum and kidney tubule cells are reported with high tissue-IHC staining (HPA tissue IHC). Choose spectrally separated fluorophores and place the weaker signal in a channel with lower tissue autofluorescence, confirming bleed-through with single-stain controls (general IF practice). Set permeabilisation according to a mapped epitope: an intracellular loop requires access across the membrane, whereas an exposed extracellular epitope may not (UniProt Q96QD8 topology; general IF practice). Compare membrane and intracellular signal with matched IHC regions.

What should I check when SLC38A2 DAB staining is widespread?

First inspect a section processed without primary antibody to identify detection-system colour, and compare it with the complete stain under identical imaging conditions (general IHC practice). Quench endogenous peroxidase before chromogenic detection and optimise DAB development time as general workflow steps, not as SLC38A2-specific requirements (general IHC practice). The selected product image used primary antibody at 1:200 overnight at 4 °C and secondary antibody at 1:200 for 45 minutes at room temperature (datasheet A03242-1). If background persists, titrate antibody and detection strength while keeping retrieval fixed, and inspect folds, damaged edges, and pigment before changing the interpretation (general IHC practice). Widespread cytoplasmic staining alone is not a specificity control (HPA tissue IHC).

How should I score SLC38A2 staining across heterogeneous paraffin sections? ⚠ ANSWER MARKED FOR VERIFICATION

Define the cell population and compartment before scoring, and keep those definitions identical across cases (general IHC practice). For tumour or epithelial regions, report the percentage of positive eligible cells and an H-score based on intensity categories; for dispersed cells, report positive cells per mm² of viable region (general IHC practice). Normalise counts to the number of eligible cells or viable tissue area, rather than total section area, and exclude folds and necrotic zones using prespecified rules (general IHC practice). Record membrane and cytoplasmic scores separately because membrane localisation and cytoplasmic tissue-IHC staining are both documented (UniProt Q96QD8 subcellular; HPA tissue IHC). Use identical exposure or image-analysis thresholds and batch controls for comparisons (general IHC practice).

Which findings support genuine SLC38A2 staining rather than artefact?

Favour signal in intact cells with a reproducible membrane or cytoplasmic distribution over colour confined to section edges, folds, or necrotic material (UniProt Q96QD8 subcellular; HPA tissue IHC; general IHC practice). High staining in kidney tubule cells or duodenal glandular cells can serve as a tissue-pattern check, while adipocytes and skeletal-muscle myocytes are reported as not detected in the cited tissue survey (HPA tissue IHC). Check the no-primary control and peroxidase block when colour appears in implausible compartments or unrelated deposits (general IHC practice). An apparent positive outside expected cell populations needs independent confirmation, because the tissue survey reports low consistency between antibody staining and RNA data (HPA tissue IHC). Interpret staining as protein distribution, not a direct measure of amino-acid transport activity (UniProt Q96QD8 function; general IHC practice).

Boster reagents

Best SLC38A2 / Sodium-coupled neutral amino acid symporter 2 IHC Antibodies

A03242-1 has an IHC image from paraffin-embedded human colon cancer (catalog image caption). Its listed reactivity covers human, mouse and rat; no IF data are supplied (catalog applications and images).

Real IHC data Immunohistochemical analysis of paraffin-embedded human Colon cancer. 1, Antibody was diluted at 1:200(4° overnight). 2, Tris-EDTA,pH9.0 was used for antigen retrieval. 3,Secondary antibody was diluted at 1:200(room temperature, 45min).

Anti-SLC38A2 Antibody

Cat # A03242-1

View product →

A03242-1 is listed for IHC and has an image from paraffin-embedded human colon cancer (catalog applications; catalog image caption). Human, mouse and rat are listed as reactive species, while the supplied image documents human tissue only (catalog reactivity; catalog image caption).

Which to pick: Choose A03242-1 for paraffin-section IHC: its image caption documents human colon cancer tissue, but does not report the fixative (catalog image caption). For mouse or rat tissue, A03242-1 has listed reactivity without a supplied tissue image for either species (catalog reactivity; catalog image caption). No SKU in this payload is listed for IF/ICC or has an IF image, so an IF/ICC choice is unsupported (catalog applications and images).

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

References

UniProt Consortium. UniProt entry Q96QD8 (S38A2_HUMAN, Sodium-coupled neutral amino acid symporter 2).
Human Protein Atlas. SLC38A2 tissue IHC expression (reliability: Approved).
Human Protein Atlas. SLC38A2 subcellular location (ICC-IF): Localized to the plasma membrane..
Human Protein Atlas. SLC38A2 antibody validation summary (2 antibodies).
Neutral amino acid transporter SLC38A2 protects renal medulla from hyperosmolarity-induced ferroptosis. eLife 2023 — PMC9949798.
Selective Alanine Transporter Utilization Creates a Targetable Metabolic Niche in Pancreatic Cancer. Cancer discovery 2020 — PMC7334074.
Micropeptide hSPAR regulates glutamine levels and suppresses mammary tumor growth via a TRIM21-P27KIP1-mTOR axis. The EMBO journal 2025 — PMC11876615.
Upregulation of SLC38A2 by melatonin attenuates hippocampal ferroptosis in Alzheimer's disease. Alzheimer's research & therapy 2026 — PMC13019843.
PubMed PMID:10930503 — UniProt-cited evidence.
PubMed PMID:10718198 — UniProt-cited evidence.
PubMed PMID:12168954 — UniProt-cited evidence.