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MAF / Transcription factor Maf · IHC design guide
Design Immunohistochemistry for MAF
Plan paraffin IHC for MAF using the nuclear staining reported in most tissues (HPA tissue IHC). This guide covers fixation consistency (standard IHC practice), the IHC-validated antibody at 1:50 (datasheet: 1:50), and the low consistency between staining and RNA expression (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
MAF 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 | Nuclear staining in most tissues (HPA tissue IHC) | |
| Staining pattern | Nuclear staining across most tissues (HPA tissue IHC) | |
| Antigen retrieval | Tris-EDTA pH 9.0 HIER, 95–98 °C, 20 min (rule: nuclear antigen) | |
| Positive control | Caudate+4 more · see all | |
| Negative control | Fallopian tube+1 more · see all |
Important caveats
Reasons your staining may differ from the expected pattern.
| Fixation | Keep fixation conditions consistent. (standard IHC practice; not target-specific) | |
| Caveat | Staining has low consistency with RNA expression (HPA tissue IHC) | |
| Regulation | MAF abundance regulation is unspecified (UniProt) | |
| Isoform / epitope | 2 isoforms; epitope effects are unknown (UniProt) |
Section 1
Recommended MAF IHC & IF Protocols
The catalog antibody’s IHC-P protocol is paired with published chromogenic MAF staining protocols for hematolymphoid tissue and laryngeal carcinoma (PMC4847138; PMC8301809).
| Sample | Paraffin-embedded human kidney tissue; fixative not specified (datasheet M00654) |
| Fixation | Image fixative and duration unreported (datasheet M00654); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat-induced epitope retrieval in Tris-EDTA buffer, pH 9.0, 20 min at 95–98 °C (standard rule: nuclear antigen) |
| 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 monoclonal (clone DHI-13) anti-MAF, 1:50 (datasheet M00654) |
| 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 | MAF-positive staining in glial cells of caudate (HPA tissue IHC: High). HPA tissue profile: Nuclear expression in most tissues. No signal in the no-primary control. |
💡Decision noteStart with Tris-EDTA pH 9.0 HIER at 95–98 °C for 20 min (page antigen-retrieval rule); optimize against an appropriate positive control.
Section 2
What Is the Expected MAF Staining Pattern?
MAF is a nuclear transcription factor with no transmembrane segment (UniProt O75444: subcellular location, topology). In paraffin-section IHC, expect nuclear staining across many tissues, with high staining reported in glial cells, kidney tubule cells, and selected glandular or respiratory epithelial cells (HPA: tissue IHC). HPA rates its tissue profile Approved but reports low consistency between antibody staining and RNA expression; interpret unexpected positives cautiously (HPA: tissue IHC reliability).
| Distinct nuclear chromogen in glial cells of caudate or cerebral cortex, or in kidney tubule cells. | This matches reported High staining in those cells (HPA: tissue IHC) and MAF's nuclear location (UniProt O75444: subcellular location). Compare signal within the named cell population; a positive tissue need not show equally strong staining in every cell. |
| Strong cytoplasmic staining with little or no identifiable nuclear signal. | That is discordant with the principal nuclear IHC profile (HPA: tissue IHC; UniProt O75444: subcellular location). HPA also reports Golgi and vesicle signal by ICC-IF, so inspect the preparation and detection controls before calling every extranuclear focus an artefact (HPA: subcellular ICC-IF). |
| Chromogen appears in an unexpected cell population, especially alongside staining in a reported negative population. | Consider cross-reactivity or endogenous detection activity (standard IHC practice). HPA reports fallopian-tube and seminal-vesicle glandular cells as Not detected, but its Approved tissue profile has low RNA–staining consistency; those observations are comparison points, not proof of universal absence (HPA: tissue IHC). |
| Diffuse color obscures nuclear boundaries throughout the section. | The slide cannot support a compartment-specific MAF call while background overwhelms nuclei (UniProt O75444: nuclear location). Check the detection blank, blocking, wash quality, and chromogen development as general IHC troubleshooting; HPA tissue staining alone does not identify which step caused the background. |
| No nuclear signal in a control section expected to stain strongly. | First confirm that the section contains the relevant cells: HPA reports High staining in glial cells of caudate, cortex, and hippocampus, and in kidney tubule cells (HPA: tissue IHC). If present, review assay performance before interpreting the study specimen as MAF negative. |
💡Expected MAF appearanceA convincing positive is discernible nuclear chromogen in the relevant cells, potentially High in HPA-listed glial or kidney tubule cells; diffuse color without resolvable nuclear enrichment is a false-positive concern (HPA: tissue IHC; UniProt O75444: nuclear location).
| Tissue and cell selection (HPA: tissue IHC). | HPA describes nuclear expression in most tissues and low tissue specificity, with High staining in specified cell populations. Use its cell-level entries to choose comparisons; a whole-organ label does not establish the intensity of every cell in that organ. |
| Strength of tissue evidence (HPA: tissue IHC reliability; HPA: antibodies). | The tissue profile is Approved, with low consistency between antibody staining and RNA expression. HPA028289 and CAB010296 are each IHC Approved; neither is listed as IHC Enhanced in the supplied antibody record. Treat an unexpected pattern as requiring controls rather than automatic confirmation. |
| Subcellular interpretation (UniProt O75444: subcellular location; HPA: subcellular ICC-IF). | UniProt places MAF in the nucleus. HPA ICC-IF approves nucleoplasm and nuclear bodies as main locations, with Golgi and vesicles as additional locations. These IF observations refine interpretation of a questionable focus but do not replace the nuclear IHC tissue profile. |
| IF/ICC Q: what pattern belongs on the separate IF/ICC guide? (HPA: subcellular ICC-IF). | A: Look mainly for nucleoplasmic and nuclear-body signal; Golgi and vesicle signal may also occur (HPA: subcellular ICC-IF). This is a localization cross-check, not an IF/ICC protocol or an expectation that chromogenic paraffin IHC resolves every reported IF compartment. |
| Isoforms and target structure (UniProt O75444: sequence, isoforms, topology). | UniProt lists 2 isoforms, a 373-aa chain, and a bZIP region at residues 288–351, with no transmembrane segment or signal peptide. The supplied record gives no antibody epitope, so it cannot establish which isoform either IHC antibody detects. |
| Situation | Likely cause | Next action |
|---|---|---|
| No staining in a reported high-staining control. | The relevant cells may be absent from the section, or an assay step may have failed; HPA reports high staining for specific cells, not every cell in an organ (HPA: tissue IHC). | Verify cell identity and section quality, then review antibody and detection controls. Recheck retrieval and antibody dilution against the validated IHC-P instructions as general IHC practice; no MAF-specific retrieval condition is supplied. |
| Color spreads across tissue or persists in the detection blank. | Nonspecific binding, incomplete washing, or endogenous detection activity can raise background (standard IHC practice). Such color cannot be assigned to MAF from appearance alone. | Compare the blank with the stained section; review blocking, washes, and detection chemistry (standard IHC practice). Score MAF only where nuclei remain distinguishable, consistent with its nuclear assignment (UniProt O75444: subcellular location). |
| Signal is cytoplasmic while nuclei remain clear. | The pattern conflicts with nuclear IHC staining (HPA: tissue IHC; UniProt O75444: subcellular location), although HPA reports additional Golgi and vesicle localization in ICC-IF (HPA: subcellular ICC-IF). | Check morphology, compartment assignment, and the detection blank; repeat with an HPA-listed IHC Approved antibody if available (HPA: antibodies). Do not transfer an ICC-IF compartment call directly to paraffin IHC. |
| Reported negative glandular cells stain strongly. | Fallopian-tube and seminal-vesicle glandular cells were Not detected in the supplied HPA tissue profile; cross-reactivity or endogenous activity is possible (HPA: tissue IHC; standard IHC practice). | Confirm the cell population and compare controls. Because HPA notes low RNA–staining consistency, describe a reproducible discrepancy without treating its negative entries as absolute biological exclusions (HPA: tissue IHC reliability). |
| Nearly every nucleus stains equally strongly. | HPA describes nuclear expression in most tissues but specifies High staining by cell population; uniform intensity alone does not validate antibody specificity (HPA: tissue IHC). | Compare the section with a reported high-staining cell population and a blank, then score cell types separately (HPA: tissue IHC; standard IHC practice). Preserve the distinction between nuclear location and evidence that the signal is target specific. |
| Weak signal varies between runs. | Assay settings may vary (standard IHC practice); the supplied UniProt and HPA records provide no MAF-specific fixation sensitivity or retrieval response. | Check run controls and documented retrieval, dilution, and detection settings against the IHC-validated antibody's instructions (standard IHC practice). Record the observed change without attributing it to MAF epitope masking or a tissue-specific fixation effect. |
Experiment evidence
IHC & IF images showing MAF staining
M00654 · IHCImmunohistochemical analysis of paraffin-embedded human kidney, using c-Maf Antibody.
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000178573-MAF/tissue/cerebral+cortex#imid_3667504
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000178573-MAF/tissue/colon#imid_3667422
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000178573-MAF/tissue/liver#imid_3667423
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000178573-MAF/tissue/kidney#imid_3667424
HPA · ICC-IF AF22Human Protein Atlas immunofluorescence, AF22, antibody HPA028289; green = MAF, blue = nucleus, red = microtubules.
HPA · ICC-IF AF22Human Protein Atlas immunofluorescence, AF22, antibody HPA028289; green = MAF, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for MAF IHC & IF
🧪Run caudate first: glial cells should show nuclear staining (HPA: High in caudate glial cells; UniProt O75444: nucleus). Use fallopian tube glandular cells as the biological negative (HPA: Not detected); cells without nuclear staining on the caudate slide provide an internal background reference, but their MAF status is unverified.
Positive control tissue: Caudate (Glial cells, HPA High)
Negative control tissue: Fallopian tube (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show MAF in AF22, Rh30, U2OS, with annotated localisation: Nucleoplasm (approved), Nuclear bodies (approved) (HPA subcellular).
Technical controls: Include a no-primary (secondary-only) control and an isotype control matched to the primary antibody’s host species, clonality, and immunoglobulin concentration. Confirm target specificity with MAF knockout tissue if available, or a peptide-block control when the immunizing peptide is available. In caudate sections, block endogenous peroxidase for chromogenic IHC; assess tissue autofluorescence if using IF (standard IHC/IF practice).
⚠️Feasibility: A target-specific fixation window and fixation effect are unreported in the supplied evidence; the M00654 paraffin-section kidney caption also leaves the fixative unreported (M00654 tissue-IHC caption). Whether MAF staining depends on antigen retrieval is unreported, so optimize retrieval with the catalog antibody’s IHC-P protocol (supplied application evidence). The supplied evidence does not establish that frozen sections or IF are easier; for caudate IF, assess tissue autofluorescence during interpretation (standard IF practice).
HPA tissue IHC evidence for MAF
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 |
|---|---|---|---|---|
| Caudate | Glial cells | High | Protein (IHC) | HPA → |
| Cerebellum | Cells in molecular layer | High | Protein (IHC) | HPA → |
| Cerebral cortex | Glial cells | High | Protein (IHC) | HPA → |
| Epididymis | Glandular cells | High | Protein (IHC) | HPA → |
| Gallbladder | Glandular cells | High | Protein (IHC) | HPA → |
Section 3
Advanced MAF IHC Tips
Troubleshoot MAF staining by evaluating retrieval, nuclear localisation, controls and scoring within the same tissue section.
How should I retrieve MAF in paraffin sections when nuclear staining is weak?
Start with Tris-EDTA at pH 9.0, heated to 95–98 °C for 20 minutes (page retrieval setting; UniProt O75444: nucleus). Cool sections in the retrieval buffer, then compare them with an otherwise identical control section to assess whether nuclear signal improves (standard IHC practice). If staining remains weak, test a shorter heating time or a citrate buffer at pH 6.0 on adjacent sections, keeping detection conditions constant (standard IHC practice). Judge the result by crisp nuclear staining and preserved morphology, since MAF is a nuclear transcription factor (UniProt O75444: nucleus and function).
Could fixation explain weak or uneven MAF staining?
The supplied product caption identifies paraffin-embedded human kidney but does not state its fixative (catalog antibody M00654: tissue-IHC caption). Consequently, target-specific fixation sensitivity is unknown; compare recorded fixation histories before assigning weak MAF staining to fixation (supplied fixation evidence; standard IHC practice). On matched sections, vary retrieval time around 20 minutes in Tris-EDTA at pH 9.0, and assess morphology alongside nuclear signal (page retrieval setting; standard IHC practice). Avoid interpreting edge-to-centre differences as a biological expression pattern until processing differences and uneven reagent coverage have been checked (standard IHC practice).
Where should convincing MAF staining appear in IHC sections?
Prioritise nuclear signal: MAF is assigned to the nucleus, and its bZIP domain spans residues 288–351 (UniProt O75444). The tissue atlas describes nuclear expression in most tissues, with high staining in kidney tubular cells among its listed examples (HPA: tissue IHC). Score a nuclear pattern separately from cytoplasmic or surface colour, and use a nuclear counterstain to verify that chromogen overlaps intact nuclei (standard IHC practice). The atlas also reports Golgi and vesicle localisation in cell imaging, so investigate reproducible extranuclear signal with controls rather than assuming it confirms tissue IHC specificity (HPA: subcellular; standard IHC practice).
How can I assess whether epitope choice affects MAF staining?
MAF has 2 listed isoforms, but the supplied record does not map the catalog antibody’s epitope to either one (UniProt O75444: isoforms; supplied antibody evidence). It also lists a bZIP domain at residues 288–351; that domain location alone cannot establish what this antibody recognises (UniProt O75444: domains; supplied antibody evidence). Check the antibody’s stated immunogen or epitope before interpreting discordant staining, and compare an independently targeted antibody on adjacent sections if one is available (standard IHC practice). Hold retrieval at Tris-EDTA pH 9.0 for 20 minutes during that comparison so processing does not confound the epitope question (page retrieval setting; standard IHC practice).
How should I follow up a MAF IHC result with multiplex IF?
Use a nuclear MAF channel alongside a marker identifying the cell population under study, then check colocalisation within segmented nuclei (UniProt O75444: nucleus; standard IF practice). Choose spectrally separated fluorophores and place the weaker signal in a channel with low measured tissue autofluorescence, using single-colour controls to check bleed-through (standard IF practice). Because MAF has no transmembrane segment and is nuclear, use a mild permeabilisation trial such as 0.1% Triton X-100 for 5 minutes to reach the intracellular epitope (UniProt O75444: topology and localisation; standard IF practice). Optimise IF fixation independently: the paraffin kidney caption reports no fixative or IF validation (catalog antibody M00654: tissue-IHC caption).
What should I change when MAF chromogenic staining has diffuse background?
First examine a section without primary antibody to identify detection-system background, and inspect whether colour follows tissue edges or damaged areas (standard IHC practice). For peroxidase detection, apply a peroxide block such as 3% hydrogen peroxide for 10 minutes, then wash thoroughly before the primary antibody (standard IHC practice). Reduce excessive primary incubation or concentration according to the antibody’s documented range, and compare a protein block of 20–30 minutes on matched sections (standard IHC practice). Accept optimisation only when background falls while distinct nuclear signal remains, consistent with MAF’s assigned localisation (UniProt O75444: nucleus; standard IHC practice).
How should I quantify MAF positive nuclei across sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and tissue region before scoring, then count nuclear-positive cells over all evaluable nuclei in that same population (UniProt O75444: nucleus; standard IHC practice). Report % positive nuclei and, when intensity is reproducible, an H-score from 0–300 based on percentages at intensity grades 0–3 (standard IHC practice). If cell abundance itself matters, report positive-cell density per mm² of viable tissue alongside the nuclear fraction (standard IHC practice). Keep retrieval, imaging and threshold settings consistent, and analyse compartments separately because the atlas reports differing cell-level staining across tissues (HPA: tissue IHC; standard IHC practice).
How do I distinguish genuine MAF positivity from a staining artefact?
A convincing result shows signal in intact nuclei within a defined cell population, consistent with MAF’s nuclear assignment and the atlas tissue profile (UniProt O75444: nucleus; HPA: tissue IHC). Question diffuse surface or cytoplasmic colour, edge-only staining and colour concentrated in necrotic areas; check matched controls before calling those cells positive (standard IHC practice). A no-primary control and a peroxidase-block comparison help identify detection background or endogenous enzyme activity in chromogenic sections (standard IHC practice). Interpret tissue patterns cautiously because the atlas rates its staining approved while reporting low consistency with RNA expression (HPA: reliability description).
Boster reagents
Best MAF / Transcription factor Maf IHC Antibodies
M00654 has a human kidney paraffin-section IHC image (M00654 image caption) and lists human, mouse, and rat reactivity (M00654 reactivity); A00654-1 lists human IF/ICC applications (A00654-1 applications/reactivity).
Real IHC data
Anti-c-Maf Rabbit Monoclonal Antibody
Cat # M00654
M00654 is the only card that will render, with its own IHC image of paraffin-embedded human kidney (M00654 image caption). Its listed application is IHC, its listed reactivity is human, mouse, and rat, and its IHC dilution is 1:50 (M00654 catalog entry).
Which to pick: Choose rabbit monoclonal M00654 for tissue IHC, including work requiring listed human, mouse, or rat reactivity (M00654 catalog entry). Its image supports paraffin-section IHC in human kidney; the fixative is unreported (M00654 image caption). For human IF/ICC, consider A00654-1, which lists those applications and human reactivity but has no IF image in the payload (A00654-1 applications/reactivity and IF image alts).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry O75444 (MAF_HUMAN, Transcription factor Maf).
- Human Protein Atlas. MAF tissue IHC expression (reliability: Approved).
- Human Protein Atlas. MAF subcellular location (ICC-IF): Mainly localized to the nucleoplasm and nuclear bodies. In addition localized to the Golgi apparatus and vesicles..
- Human Protein Atlas. MAF antibody validation summary (2 antibodies).
- Sequential and combinatorial roles of maf family genes define proper lens development. Molecular vision 2007 — PMC2503189.
- c-MAF deletion in adult C57BL/6J mice induces cataract formation and abnormal differentiation of lens fiber cells. Experimental animals 2020 — PMC7220708.
- Characterization of c-Maf transcription factor in normal and neoplastic hematolymphoid tissue and its relevance in plasma cell neoplasia. American journal of clinical pathology 2009 — PMC4847138.
- Loss of the MAF Transcription Factor in Laryngeal Squamous Cell Carcinoma. Biomolecules 2021 — PMC8301809.
- PubMed PMID:9616139 — UniProt-cited evidence.
- PubMed PMID:15616553 — UniProt-cited evidence.
- PubMed PMID:15489334 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for MAF (Transcription factor Maf). Expected localisation Nuclear staining in most tissues (HPA tissue IHC). Antigen retrieval: Tris-EDTA pH 9.0 HIER, 95–98 °C, 20 min (rule: nuclear antigen). Validated IHC antibody: M00654 at 1:50 (the product's own IHC validation image is shown). Controls (HPA): positive Caudate (Glial cells); negative Fallopian tube. IHC workflow; specimen preparation unspecified. Protocol steps: 1. Sample: Paraffin-embedded human kidney tissue; fixative not specified (datasheet M00654); 2. Fixation: Image fixative and duration unreported (datasheet M00654); 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-induced epitope retrieval in Tris-EDTA buffer, pH 9.0 , 20 min at 95–98 °C…; 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% normal serum of the secondary host, 30 min , room temperature (standard); 8. Primary antibody: Rabbit monoclonal (clone DHI-13) anti-MAF, 1:50 (datasheet M00654); 9. Primary incubation: Overnight at 4 °C (standard). Watch for: Fixation: Keep fixation conditions consistent. (standard IHC practice; not target-specific); Caveat: Staining has low consistency with RNA expression (HPA tissue IHC); Isoform / epitope: 2 isoforms; epitope effects are unknown (UniProt); Regulation: MAF abundance regulation is unspecified (UniProt). Evidence: UniProt O75444, HPA tissue IHC · Approved, HPA ICC-IF · Mainly localized to the nucleoplasm and nuclear bodies. In addition…, Datasheet M00654, PMC4847138, PMC8301809. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/MAF/immunohistochemistry-ihc-guide.