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TFRC / Transferrin receptor protein 1 · IHC design guide
Design Immunohistochemistry for TFRC
Plan chromogenic TFRC IHC in paraffin sections using placental trophoblasts or bone marrow hematopoietic cells as positive controls (HPA tissue IHC). Score membranous and cytoplasmic staining by cell type (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
TFRC 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 and membranous staining (HPA tissue IHC) | |
| Staining pattern | Strong in trophoblasts and marrow cells; membranous/cytoplasmic (HPA tissue IHC) | |
| Antigen retrieval | Citrate pH 6 HIER, heat-mediated (datasheet PB9233) | |
| Positive control | Bone marrow+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); Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image PB9233) | |
| Caveat | Secreted variant may complicate RNA–staining comparisons (HPA tissue IHC) | |
| Regulation | Expression regulation not annotated (UniProt) | |
| Isoform / epitope | No isoforms listed; serum form lacks cytoplasmic epitopes (UniProt) |
Section 1
Recommended TFRC IHC & IF Protocols
The catalog antibody's IHC-P protocol (datasheet: PB9233) is accompanied by two published paraffin-section TFRC protocols (PMC11045412; PMC11379720).
| Sample | Paraffin-embedded human placenta tissue; fixative not specified (datasheet PB9233) |
| Fixation | Image fixative and duration unreported (datasheet PB9233); 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 PB9233) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet PB9233) |
| Primary antibody | Rabbit anti-TFRC, 0.5-1μg/ml (datasheet PB9233) |
| Primary incubation | Overnight at 4 °C (datasheet PB9233) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet PB9233) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | TFRC-positive staining in hematopoietic cells of bone marrow (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic and membranous expression in most tissues, highly abundant in placental trophoblasts and bone marrow cells. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated citrate retrieval at pH 6 (datasheet: PB9233); one published protocol specifies 95 °C for 15 min (PMC11379720).
Section 2
What Is the Expected TFRC Staining Pattern?
TFRC is a cell membrane receptor with a cytoplasmic segment at residues 1–67 and an extracellular segment at 89–760 (UniProt P02786 topology). In IHC, expect cytoplasmic and membranous staining, especially in placental trophoblastic cells, bone marrow hematopoietic cells, and lung macrophages (HPA tissue IHC: Enhanced reliability; High in these cell populations).
| Membranous staining with cytoplasmic signal in the expected cells. | This matches the reported tissue pattern (HPA tissue IHC). Compare cells within the section: placental trophoblastic cells, bone marrow hematopoietic cells, and lung macrophages have High staining (HPA tissue IHC). Cytoplasmic signal can reflect TFRC trafficking through endosomes (UniProt P02786 function). |
| Predominantly nuclear staining, with little membrane or cytoplasmic signal. | Nuclear staining alone conflicts with TFRC cell membrane localization (UniProt P02786 subcellular location) and the reported tissue IHC pattern (HPA tissue IHC). Treat it as suspect; assess morphology, negative controls, and an independently validated antibody before assigning it to TFRC (general IHC practice). |
| Strong staining in cells expected to be undetected, such as adipocytes. | Adipocytes are reported as Not detected (HPA tissue IHC). Check cell identity before calling the result discordant. If staining remains in the same cells, consider antibody cross-reactivity or endogenous chromogen-generating activity and compare negative controls (general IHC practice). |
| Diffuse staining across tissue structures without a clear cellular pattern. | An even haze is difficult to reconcile with the reported cell-selective High and Not detected observations (HPA tissue IHC). Examine a no-primary control and staining outside tissue, then reassess blocking, washes, and detection conditions (general IHC practice). |
| No staining in placental trophoblastic cells or bone marrow hematopoietic cells. | Both populations are reported High (HPA tissue IHC), so an absent signal warrants a run check. Confirm the expected cells are present, compare a concurrently stained positive section, and review antibody, retrieval, and detection conditions (general IHC practice). |
💡Expected TFRC appearanceCall a section positive when expected cells show clear membranous and cytoplasmic staining—typically High in placental trophoblastic cells, bone marrow hematopoietic cells, or lung macrophages (HPA tissue IHC); isolated nuclear staining or uniform haze is suspect (UniProt P02786 subcellular location; HPA tissue IHC).
| Cellular distribution | HPA reports cytoplasmic and membranous expression in most tissues, with particularly abundant staining in placental trophoblastic and bone marrow cells (HPA tissue IHC). Its Low tissue RNA specificity does not mean every cell stains equally (HPA tissue IHC). Score the relevant cell population, not whole-section color. |
| Receptor topology and trafficking | TFRC has one membrane-spanning segment at residues 68–88 (UniProt P02786 topology). Ligand-bound receptor enters endosomes and recycles to the surface (UniProt P02786 function), supporting a membrane-plus-cytoplasmic interpretation. Topology alone does not establish which epitope a particular antibody recognizes. |
| Processing and circulating form | UniProt lists a full-length 1–760 chain and a serum form spanning 101–760 (UniProt P02786 processing). Secreted protein can complicate a simple RNA-to-tissue-staining comparison (HPA tissue IHC reliability description); extracellular color alone does not identify its source. |
| Antibody evidence | The tissue profile has Enhanced reliability, with medium consistency between antibody staining and RNA expression (HPA tissue IHC). Two listed antibodies, HPA028598 and CAB000153, each have Enhanced IHC validation (HPA antibody validation). This supports comparison of patterns, without guaranteeing a particular catalog antibody's specificity. |
| IF/ICC Q: Should the same compartment pattern appear in cultured cells? | A: Endosomes and lysosomes are the supported main ICC-IF locations (HPA subcellular). That intracellular pattern fits receptor cycling (UniProt P02786 function). Interpret fluorescence using the separate IF/ICC guide; an IHC tissue result does not establish an IF staining protocol. |
| Situation | Likely cause | Next action |
|---|---|---|
| Positive-control section lacks staining. | A missed cell population or a run-level reagent, retrieval, or detection problem is possible (general IHC practice). | Verify that placental trophoblastic cells or bone marrow hematopoietic cells are present; both are High (HPA tissue IHC). Check a concurrently stained positive section and the run records (general IHC practice). |
| Signal is nuclear-only. | This conflicts with reported cell membrane localization (UniProt P02786 subcellular location) and cytoplasmic/membranous tissue staining (HPA tissue IHC). | Inspect morphology and no-primary controls, then compare an independently validated antibody if available (general IHC practice; HPA antibody validation). |
| Adipocytes stain strongly. | Adipocytes are Not detected (HPA tissue IHC); cell misidentification, cross-reactivity, or endogenous detection activity may explain the result (general IHC practice). | Confirm cell identity, examine a no-primary control, and check detection blocking before scoring adipocytes as TFRC-positive (general IHC practice). |
| Background obscures cell borders. | Nonspecific binding, incomplete blocking, or insufficient washing can raise chromogenic background (general IHC practice). | Compare a no-primary control, optimize blocking and washes, and judge whether expected cells retain a distinct membranous/cytoplasmic pattern (general IHC practice; HPA tissue IHC). |
| A reportedly negative tissue contains some stained cells. | HPA's Not detected calls refer to named cell populations; other cells in a section can differ (HPA tissue IHC). | Identify the stained cells before judging the result. Compare the specified population—for example, skeletal muscle myocytes, reported Not detected (HPA tissue IHC)—with controls (general IHC practice). |
| IHC shows cytoplasmic signal while ICC-IF shows puncta. | Tissue IHC reports cytoplasmic and membranous expression (HPA tissue IHC); ICC-IF places TFRC mainly in endosomes and lysosomes (HPA subcellular). | Interpret each assay in its own cellular context and compare the compartment assignments; do not score punctate intracellular signal as a contradiction by itself (HPA tissue IHC; HPA subcellular). |
Experiment evidence
IHC & IF images showing TFRC staining
PB9233 · IHCIHC analysis of TFRC using anti-TFRC antibody (PB9233). TFRC was detected in paraffin-embedded section of human placenta tissue. Heat mediat
PB9233 · IHCIHC analysis of TFRC using anti-TFRC antibody (PB9233). TFRC was detected in frozen section of human placenta tissues. The tissue section wa
PB9233 · IFIF analysis of TFRC using anti-TFRC antibody (PB9233). TFRC was detected in immunocytochemical section of A431 cells. Enzyme antigen retriev
M00591-1 · IHCIHC analysis of CD71 using anti-CD71 antibody (M00591-1). CD71 was detected in a paraffin-embedded section of human placenta tissue. Heat me
M00591-4 · IHCHuman kidney was stained with anti-Transferrin Receptor rabbit antibody
M00591-4 · IHCHuman placenta was stained with anti-Transferrin Receptor rabbit antibody
A00591S24 · IHCImmunohistochemistry analysis of paraffin-embedded human brain, using CD71/TfR (Phospho-Ser24) Antibody. The picture on the right is blocked
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000072274-TFRC/tissue/cerebral+cortex#imid_406282
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000072274-TFRC/tissue/colon#imid_406200
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000072274-TFRC/tissue/liver#imid_406201
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000072274-TFRC/tissue/kidney#imid_406210
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody CAB000153; green = TFRC, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody CAB000153; green = TFRC, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for TFRC IHC & IF
🧪Run placenta first and expect trophoblastic cells to stain (HPA: High in placental trophoblastic cells; selected PB9233 tissue-IHC caption: placenta). Use salivary gland as the negative tissue (HPA: Not detected in salivary glandular cells); on the placenta slide, assess morphologically distinct non-trophoblastic cells for counterstain-only, background-level signal, without assuming every such cell is TFRC-negative (standard IHC practice).
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 ICC-IF images show TFRC in A-431, U-251MG, U2OS, with annotated localisation: Endosomes (supported), Lysosomes (supported) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control, a concentration-matched rabbit IgG isotype control, and a TFRC-knockout biological negative where available (selected PB9233 tissue-IHC caption: rabbit primary; standard IHC practice). Block endogenous peroxidase and check endogenous biotin in placenta because the reported detection uses a biotinylated secondary, streptavidin–biotin complex, and DAB (selected PB9233 tissue-IHC caption; standard IHC practice).
⚠️Feasibility: The selected PB9233 paraffin-section caption does not report a fixative, and the supplied evidence reports no target-specific fixation window or fixation effect (selected PB9233 tissue-IHC caption). The reported IHC procedure uses heat retrieval in citrate buffer at pH 6 for 20 minutes, but the evidence does not establish that retrieval is required for every antibody or preparation (selected PB9233 tissue-IHC caption). Frozen sections or IF/ICC are not established as easier by the supplied evidence; for this placenta IHC procedure, endogenous biotin or peroxidase can complicate DAB interpretation (selected PB9233 tissue-IHC caption; standard IHC practice).
HPA tissue IHC evidence for TFRC
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — Medium consistency between antibody staining and RNA expression data. At least one protein variant secreted, tissue location of RNA and protein might differ and correlation is complex.). 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 → |
| Lung | Macrophages | High | Protein (IHC) | HPA → |
| Placenta | Trophoblastic cells | High | Protein (IHC) | HPA → |
| Adrenal gland | Glandular cells | Medium | Protein (IHC) | HPA → |
| Appendix | 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 → |
| Salivary gland | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Seminal vesicle | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Skeletal muscle | Myocytes | Not detected | Protein (IHC) | HPA → |
| Spleen | Cells in red pulp | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced TFRC IHC Tips
Use the catalog antibody’s paraffin-section IHC evidence alongside TFRC topology and tissue patterns to troubleshoot staining and interpret chromogenic signal.
Which retrieval condition should I start with for TFRC in paraffin sections?
Start with heat-mediated citrate retrieval at pH 6 for 20 minutes in paraffin sections (datasheet PB9233). The selected placenta image used this condition, followed by 10% goat serum and 1 μg/mL primary antibody overnight at 4°C (datasheet PB9233). If staining remains weak, compare retrieval times on adjacent sections before testing another buffer, while keeping antibody concentration and detection conditions fixed (standard IHC practice). Judge signal alongside preserved tissue morphology and staining in trophoblastic cells, which are a strong expected population (HPA: High in placental trophoblastic cells; standard IHC practice).
How should I troubleshoot fixation-related loss of TFRC staining?
The selected placenta caption describes a paraffin section but does not state its fixative, so TFRC-specific fixation sensitivity is unknown (datasheet PB9233). Record each specimen’s fixative and fixation duration, then compare sections processed with the same citrate retrieval at pH 6 for 20 minutes (datasheet PB9233; standard IHC practice). Keep section thickness, primary incubation, and detection conditions consistent while investigating a fixation difference (standard IHC practice). Include a similarly processed placenta section as a positive reference, and assess staining in trophoblastic cells together with morphology (HPA: High in placental trophoblastic cells; standard IHC practice).
Should TFRC staining be membranous, cytoplasmic, or both?
Score membranous and vesicular cytoplasmic staining as plausible TFRC patterns: the receptor spans residues 68–88, with a cytoplasmic N-terminus and extracellular remainder (UniProt P02786 topology). Its ligand-bound complex enters endosomes and recycles to the surface, supporting both locations in tissue sections (UniProt P02786 function). Tissue IHC also reports cytoplasmic and membranous expression across most tissues (HPA: tissue IHC profile). Compare compartment patterns in trophoblastic cells or bone marrow hematopoietic cells against adjacent negative controls before calling diffuse staining specific (HPA: High in these cell populations; standard IHC practice).
Could epitope location or processing explain discordant TFRC IHC results?
Check the catalog antibody’s documented immunogen or epitope before comparing stains; its precise epitope is not supplied here (datasheet PB9233). TFRC has 0 annotated isoforms, but the record lists a full-length 1–760 chain and a serum form spanning 101–760 (UniProt P02786 processing). An antibody directed to residues 1–100 could therefore distinguish these forms, whereas an antibody recognizing a shared region would not do so on sequence alone (UniProt P02786 processing; standard epitope interpretation). Glycosylation sites at 104, 251, 317, and 727 warrant caution when interpreting epitope accessibility after retrieval (UniProt P02786 glycosylation; standard IHC practice).
How can IF help resolve an ambiguous TFRC IHC pattern?
Use IF/ICC as a companion localisation experiment and multiplex TFRC with a marker identifying the expected cell population, such as placental trophoblastic cells (HPA: High in placental trophoblastic cells; standard IF practice). Choose spectrally separated fluorophores and favor a longer-wavelength TFRC channel if the specimen has strong tissue autofluorescence (standard IF practice). Select permeabilisation according to the antibody’s documented epitope: access to residues 1–67 requires membrane access, whereas residues 89–760 face outward at the cell surface (UniProt P02786 topology; standard IF practice). Compare nonpermeabilised and permeabilised preparations with matched controls, then assess surface and intracellular signal against the chromogenic IHC pattern (UniProt P02786 function; standard IF practice).
What should I check when TFRC DAB staining is widespread or muddy?
First compare a no-primary control with the stained section to identify signal arising from detection reagents or tissue rather than primary-antibody binding (standard IHC practice). The selected placenta workflow used a biotinylated secondary, streptavidin–biotin detection, and DAB, so check for endogenous biotin and endogenous peroxidase activity (datasheet PB9233; standard IHC practice). Apply a peroxidase block and assess whether additional biotin blocking or a different detection system reduces control staining (standard IHC practice). Recheck primary concentration against the demonstrated 1 μg/mL condition and inspect tissue edges separately from intact central regions before scoring TFRC (datasheet PB9233; standard IHC practice).
How should I quantify TFRC IHC across tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and compartment before scoring, because TFRC can appear at the cell membrane and within cytoplasmic vesicles (UniProt P02786 topology and function). For comparable regions, report the percentage of positive cells and an H-score from 0–300, using consistent intensity thresholds and blinded review (standard IHC practice). Normalise each result to the number of evaluable cells in the specified population; use positive-cell density per mm² only when tissue area is the intended denominator (standard IHC practice). Track section quality and batch controls, and avoid treating staining intensity alone as a direct measure of iron uptake (UniProt P02786 function; standard IHC practice).
How can I distinguish true TFRC staining from artefact?
Look for membranous or vesicular cytoplasmic signal in plausible cells, including placental trophoblastic cells and bone marrow hematopoietic cells (UniProt P02786 topology and function; HPA: High in these populations). Predominantly nuclear staining conflicts with the documented receptor topology and should prompt control review before interpretation (UniProt P02786 topology; standard IHC practice). Exclude necrotic regions, folds, and section edges when staining concentrates there without a matching cellular pattern (standard IHC practice). If a no-primary control retains DAB signal, investigate endogenous peroxidase or biotin-associated detection background before attributing staining to TFRC (datasheet PB9233 detection method; standard IHC practice).
Boster reagents
Best TFRC / Transferrin receptor protein 1 IHC Antibodies
Validated anti-TFRC antibodies have IHC images from human placenta, kidney, and brain and mouse and rat kidney; IF images cover A431 cells and human placenta (catalog image captions).
Real IHC data
Anti-Transferrin Receptor/TFRC Antibody ®
Cat # PB9233
Real IHC data
Anti-Transferrin Receptor (CD71) TFRC Rabbit Monoclonal Antibody
Cat # M00591-1
Real IHC data
Anti-Transferrin Receptor Rabbit Monoclonal Antibody
Cat # M00591-4
Real IHC data
Anti-Phospho-CD71 (S24) TFRC Antibody
Cat # A00591S24
PB9233 shows paraffin-section IHC in human placenta and IF in A431 cells and human placenta (PB9233 image captions); M00591-1 shows paraffin-section IHC in human placenta (M00591-1 IHC caption). M00591-4 shows IHC in human kidney and placenta and mouse and rat kidney (M00591-4 IHC captions); A00591S24 shows phospho-Ser24 IHC in paraffin-embedded human brain with phosphopeptide blocking (A00591S24 IHC caption).
Which to pick: For human tissue IHC, PB9233 shows paraffin placenta after citrate retrieval at pH 6, while monoclonal M00591-1 shows paraffin placenta after EDTA retrieval at pH 8; neither caption reports the fixative (PB9233 and M00591-1 IHC captions; M00591-1 catalog). For IF/ICC, choose PB9233: both applications are listed, and its IF images show A431 cells and human placenta (PB9233 catalog and IF captions). For cross-species tissue IHC, choose monoclonal M00591-4, whose IHC images cover human, mouse, and rat kidney; its captions do not report the fixative (M00591-4 catalog and IHC captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P02786 (TFR1_HUMAN, Transferrin receptor protein 1).
- Human Protein Atlas. TFRC tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. TFRC subcellular location (ICC-IF): Mainly localized to the endosomes and lysosomes..
- Human Protein Atlas. TFRC antibody validation summary (2 antibodies).
- Novel insights into immune-related genes associated with type 2 diabetes mellitus-related cognitive impairment. World journal of diabetes 2024 — PMC11045412.
- Dual-Multivalent Aptamer-Based Drug Delivery Platform for Targeted SRC Silencing to Enhance Doxorubicin Sensitivity in Endometrial Cancer. International journal of biological sciences 2024 — PMC11628347.
- Comparative Analysis of Ferroptosis- and Mitochondria-Related Genes in Ischemic Stroke via Bioinformatics Analysis and Experimental Validation. Journal of inflammation research 2026 — PMC13367347.
- RAB17 promotes endometrial cancer progression by inhibiting TFRC-dependent ferroptosis. Cell death & disease 2024 — PMC11379720.
- PubMed PMID:6090955 — UniProt-cited evidence.
- PubMed PMID:6094009 — UniProt-cited evidence.
- PubMed PMID:9358047 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for TFRC (Transferrin receptor protein 1). Expected localisation Cytoplasmic and membranous staining (HPA tissue IHC). Antigen retrieval: Citrate pH 6 HIER, heat-mediated (datasheet PB9233). Validated IHC antibody: PB9233 at 0.5-1μg/ml (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 placenta tissue; fixative not specified (datasheet PB9233); 2. Fixation: Image fixative and duration unreported (datasheet PB9233); 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 PB9233); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet PB9233); 8. Primary antibody: Rabbit anti-TFRC, 0.5-1μg/ml (datasheet PB9233); 9. Primary incubation: Overnight at 4 °C (datasheet PB9233). Watch for: Fixation: Keep fixation consistent across sections (standard IHC practice; not target-specific); Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image PB9233); Caveat: Secreted variant may complicate RNA–staining comparisons (HPA tissue IHC); Isoform / epitope: No isoforms listed; serum form lacks cytoplasmic epitopes (UniProt); Regulation: Expression regulation not annotated (UniProt). Evidence: UniProt P02786, HPA tissue IHC · Enhanced, HPA ICC-IF · Mainly localized to the endosomes and lysosomes., Datasheet PB9233, PMC11045412, PMC11379720. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/TFRC/immunohistochemistry-ihc-guide.