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MCM4 / DNA replication licensing factor MCM4 · IHC design guide
Design Immunohistochemistry for MCM4
Plan chromogenic MCM4 IHC in paraffin sections around variable nuclear staining (HPA tissue IHC). Start with the catalog antibody’s 2–5 μg/ml IHC range and compare high-staining with low-staining cell populations (datasheet A02301-1; HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
MCM4 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 | Variable nuclear staining across tissues (HPA tissue IHC) | |
| Staining pattern | Nuclei stain at variable levels across tissue cell types (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A02301-1) | |
| Positive control | Appendix+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 | Keep paraffin-section fixation consistent across samples (standard IHC practice; not target-specific) | |
| Caveat | Chromatin association changes as replication proceeds (UniProt) | |
| Regulation | Nuclear expression varies across tissues (HPA tissue IHC) | |
| Isoform / epitope | No annotated isoforms; mature chain spans residues 2–863 (UniProt) |
Section 1
Recommended MCM4 IHC & IF Protocols
The catalog antibody uses EDTA pH 8.0 retrieval (datasheet A02301-1). Published MCM4 IHC methods below cover urothelial, pancreatic, and esophageal samples (PMC10515259; PMC12967608; PMC5250507).
| Sample | Paraffin-embedded mouse colon tissue; fixative not specified (datasheet A02301-1) |
| Fixation | Image fixative and duration unreported (datasheet A02301-1); 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 A02301-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A02301-1) |
| Primary antibody | Rabbit anti-MCM4, 2-5μg/ml (datasheet A02301-1) |
| Primary incubation | Overnight at 4 °C (datasheet A02301-1) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet A02301-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | MCM4-positive staining in germinal center cells of appendix (HPA tissue IHC: High). HPA tissue profile: Nuclear expression at variable levels in all tissues. No signal in the no-primary control. |
💡Decision noteStart with EDTA pH 8.0 heat retrieval for the catalog antibody (datasheet A02301-1). The urothelial study used pH 9 retrieval (PMC10515259).
Section 2
What Is the Expected MCM4 Staining Pattern?
MCM4 should stain nuclei, including germinal center cells in appendix and hematopoietic cells in bone marrow (HPA tissue IHC: High). Nuclear staining varies across tissues (HPA tissue IHC: Enhanced reliability; medium staining–RNA consistency). Its nuclear and chromosomal localization, with no transmembrane segment, supports a nuclear interpretation (UniProt P33991: subcellular location and topology).
| Clear nuclear chromogen in appendix germinal center cells or bone marrow hematopoietic cells. | This matches reported high staining in those cells (HPA tissue IHC: High). Score the proportion and intensity of stained nuclei within the identified cell population; compare runs against the same positive tissue (general IHC practice). |
| Predominantly cytoplasmic or membrane staining, with nuclei unstained. | That compartment conflicts with the nuclear tissue pattern (HPA tissue IHC: nuclear expression) and nuclear/chromosomal localization (UniProt P33991). Check morphology, counterstain and detection controls before interpreting it as MCM4 (general IHC practice). |
| Strong signal in cells expected to stain weakly, such as smooth muscle cells or liver cholangiocytes. | These cells have low reported staining (HPA tissue IHC: Low). Unexpected intensity may reflect cross-reactivity or endogenous detection activity; it does not establish either cause without controls (general IHC practice). |
| Diffuse chromogen obscures nuclei and tissue boundaries. | The distribution cannot be scored reliably against the expected nuclear pattern (HPA tissue IHC: nuclear expression). Review no-primary control, blocking, washes and antibody concentration to locate nonspecific background (general IHC practice). |
| No nuclear signal in appendix germinal center cells or bone marrow hematopoietic cells. | Those cells are reported High (HPA tissue IHC). First verify tissue identity, section integrity, positive control and detection reagents; absence alone cannot distinguish a technical failure from a sample-specific result (general IHC practice). |
💡Expected MCM4 appearanceCall a result positive when distinct nuclei show chromogen in the expected cell population, with strong examples in appendix germinal center cells or bone marrow hematopoietic cells (HPA tissue IHC: High); isolated cytoplasmic or diffuse staining is suspect against the reported nuclear pattern (HPA tissue IHC).
| Compartment and cell cycle | MCM4 is nuclear and chromosomal and participates in the MCM2–7 replication helicase (UniProt P33991). It associates with chromatin before nuclei form and detaches as replication progresses (UniProt P33991); interpret variation with morphology and controls, without assigning a cell-cycle phase from stain intensity alone. |
| Tissue range and control choice | Nuclear expression varies across all tissues; the supplied HPA profile lists high and low examples but no negative tissue (HPA tissue IHC). Appendix germinal center cells or bone marrow hematopoietic cells provide documented high-staining reference populations (HPA tissue IHC: High). |
| Strength of pattern evidence | The tissue profile has Enhanced reliability with medium agreement between staining and RNA (HPA tissue IHC). Two listed antibodies have Enhanced IHC validation, HPA004873 and CAB004497 (HPA antibodies); this supports the pattern without validating every reagent or specimen. |
| Processing and epitope claims | No signal peptide or propeptide is annotated; the reported chain spans residues 2–863 (UniProt P33991). Phosphorylation and an MCM ATPase domain are annotated (UniProt P33991), but the payload gives no antibody epitope or target-specific retrieval or fixation effect; optimize retrieval empirically (general IHC practice). |
| What should IF/ICC show? | Nucleoplasmic localization is the reported IF pattern (HPA subcellular: Nucleoplasm, enhanced), consistent with nuclear localization (UniProt P33991). IF/ICC images and antibody validation are separate from this paraffin-section chromogenic IHC interpretation (HPA subcellular; HPA antibodies). |
| Situation | Likely cause | Next action |
|---|---|---|
| Known high-staining cells have no nuclear signal. | Tissue selection, retrieval, antibody incubation or detection may have failed (general IHC practice); high staining is reported for appendix germinal center and bone marrow hematopoietic cells (HPA tissue IHC). | Confirm the reference cells on the counterstain, run a known-positive section, then check retrieval conditions and each detection step (general IHC practice). |
| Cytoplasm or membranes stain more strongly than nuclei. | This disagrees with nuclear localization (UniProt P33991; HPA tissue IHC). Nonspecific binding or misread chromogen is possible (general IHC practice). | Inspect nuclear boundaries, compare a no-primary control and repeat with an IHC-validated antibody if available (general IHC practice; HPA antibodies: Enhanced IHC validation). |
| Low-staining reference cells show intense chromogen. | Smooth muscle cells and liver cholangiocytes are reported Low (HPA tissue IHC). Cross-reactivity or endogenous detection activity is possible (general IHC practice). | Check a no-primary control and any detection-only control; review enzyme blocking and whether signal stays within nuclei (general IHC practice). |
| Background covers the section or pools at edges. | A diffuse deposit prevents comparison with the reported nuclear pattern (HPA tissue IHC); excess reagent or inadequate washing is possible (general IHC practice). | Review antibody concentration, blocking, wash steps and section handling; retain the same positive tissue while changing one condition at a time (general IHC practice). |
| Nuclear staining varies markedly between tissue regions. | Variable nuclear expression is reported (HPA tissue IHC). Uneven processing or different cell populations can also alter the apparent pattern (general IHC practice). | Score identified cell types separately and compare intact regions with the same run's positive control before attributing the variation to MCM4 (general IHC practice). |
| An unstained cell population is being used as a negative control. | The supplied profile reports nuclear expression at variable levels in all tissues and lists no negative tissue (HPA tissue IHC). | Use no-primary and detection controls to assess background; treat HPA Low populations as relative comparators, not proven MCM4-negative cells (general IHC practice; HPA tissue IHC: Low). |
Experiment evidence
IHC & IF images showing MCM4 staining
A02301-1 · IHCIHC analysis of MCM4 using anti-MCM4 antibody (A02301-1). MCM4 was detected in paraffin-embedded section of mouse colon tissue. Heat mediate
A02301-1 · IHCIHC analysis of MCM4 using anti-MCM4 antibody (A02301-1). MCM4 was detected in paraffin-embedded section of rat colon tissue. Heat mediated
A02301-1 · IFIF analysis of MCM4 using anti-MCM4 antibody (A02301-1). MCM4 was detected in immunocytochemical section of A431 cells. Enzyme antigen retri
M02301 · IHCIHC analysis of MCM4 using anti-MCM4 antibody (M02301). MCM4 was detected in a paraffin-embedded section of human colorectal adenocarcinoma
M02301 · IHCIHC analysis of MCM4 using anti-MCM4 antibody (M02301). MCM4 was detected in a paraffin-embedded section of human spleen tissue. Heat mediat
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000104738-MCM4/tissue/cerebral+cortex#imid_1878204
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000104738-MCM4/tissue/colon#imid_1878138
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000104738-MCM4/tissue/liver#imid_1878147
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000104738-MCM4/tissue/kidney#imid_1878148
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA031052; green = MCM4, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA031052; green = MCM4, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for MCM4 IHC & IF
🧪Run appendix first and assess nuclear staining in germinal center cells, which HPA scores High for MCM4 (HPA: appendix, germinal center cells, High; UniProt P33991: nucleus). HPA detects MCM4 in all 45 scored tissues, so there is no HPA negative tissue; use no-primary and isotype slides as negative controls, and assess cells without brown nuclear signal on the positive slide as local background without assuming they lack MCM4 (HPA: no negative rows; MCM4 detected in all 45 scored tissues).
Positive control tissue: Appendix (Germinal center cells, HPA High)
Negative control tissue: None in HPA: MCM4 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 MCM4 in A-431, A-549, U2OS, U-251MG, U2OS, siRNA 1 (10x), U2OS, siRNA 1 (40x), U2OS, siRNA 2 (10x), U2OS, siRNA 2 (40x), U2OS, scrambled (10x), U2OS, scrambled (40x), NIH 3T3, with annotated localisation: Nucleoplasm (enhanced) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only slide, a rabbit IgG isotype control matched to the primary antibody’s clonality where available, and a matched MCM4 knockout specimen as a biological specificity control (selected A02301-1 caption: rabbit primary and goat anti-rabbit secondary). For appendix sections developed with peroxidase and a biotin-based detection system, block endogenous peroxidase and check for endogenous biotin background (selected A02301-1 caption: biotinylated secondary, SABC and DAB).
⚠️Feasibility: No target-specific fixation window or fixation effect is reported in the supplied evidence, and the selected A02301-1 tissue-IHC caption does not report a fixative (selected A02301-1 caption: fixative unreported). That paraffin-section caption uses heat retrieval in EDTA at pH 8.0 for mouse colon; it does not establish a retrieval requirement for appendix (selected A02301-1 caption: mouse colon, EDTA retrieval). The supplied evidence gives no basis to call frozen sections or IF easier than paraffin IHC; check for endogenous biotin background if using the caption’s biotin-based detection in appendix (selected A02301-1 caption: biotinylated secondary and SABC).
HPA tissue IHC evidence for MCM4
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — 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 |
|---|---|---|---|---|
| Appendix | Germinal center cells | High | Protein (IHC) | HPA → |
| Bone marrow | Hematopoietic cells | High | Protein (IHC) | HPA → |
| Breast | Glandular cells | High | Protein (IHC) | HPA → |
| Bronchus | Basal cells | High | Protein (IHC) | HPA → |
| Caudate | Glial cells | High | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| None in HPA: MCM4 is detected in all 45 scored tissues. Use a no-primary (secondary-only) and an isotype control instead. | ||||
Section 3
Advanced MCM4 IHC Tips
Troubleshoot MCM4 staining by checking nuclear localisation, retrieval, controls and scoring against the documented paraffin-section workflow.
Which retrieval conditions should I try first for weak MCM4 staining?
Start with heat-mediated retrieval in EDTA at pH 8.0 for paraffin sections (datasheet A02301-1). The documented mouse colon section used this retrieval before incubation with 2 µg/mL antibody overnight at 4°C (datasheet A02301-1). If nuclear staining is weak, repeat the run with controlled heating and cooling, then check section adhesion and whether the retrieval buffer maintained its stated pH (standard IHC practice). Compare test sections with the same detection and development conditions, because changes in those steps can obscure a retrieval effect (standard IHC practice). Record nuclear signal and tissue damage together when selecting conditions (standard IHC practice).
Could fixation explain absent or uneven MCM4 staining?
Target-specific sensitivity of MCM4 to fixation is unknown from the supplied evidence; the paraffin-section caption does not state a fixative (datasheet A02301-1). Record the actual fixative and fixation duration for each specimen, then compare sections processed together before changing antibody conditions (standard IHC practice). Excessive or uneven fixation can affect antigen accessibility in IHC generally, but its effect on this MCM4 epitope has not been established here (standard IHC practice; datasheet A02301-1). Begin troubleshooting with the documented EDTA retrieval at pH 8.0 and the documented 2 µg/mL antibody concentration (datasheet A02301-1). Evaluate nuclear signal alongside morphology to distinguish staining loss from tissue damage (standard IHC practice; UniProt P33991 localisation).
Where should convincing MCM4 staining appear in a paraffin section?
Score convincing MCM4 signal primarily in nuclei: UniProt places MCM4 in the nucleus and on chromosomes, while HPA reports variable nuclear expression across tissues (UniProt P33991 localisation; HPA tissue IHC). HPA further identifies the nucleoplasm as its enhanced subcellular location (HPA subcellular). Inspect nuclear detail at high magnification and compare the stained section with its counterstain before calling faint cytoplasmic colour positive (standard IHC practice; HPA subcellular). Chromatin association can change as DNA replication progresses, so nuclear intensity need not be uniform across cells (UniProt P33991 localisation). Persistent diffuse cytoplasmic or surface staining warrants checks of background and detection controls before interpretation (UniProt P33991 topology; standard IHC practice).
How should epitope uncertainty affect interpretation of MCM4 IHC?
The supplied UniProt record lists 0 isoforms and no transmembrane segment, so it provides no isoform-specific staining pattern to score (UniProt P33991 isoforms and topology). MCM4 has annotated phosphorylation sites near its N terminus and an AAA(+) ATPase domain at residues 441–775 (UniProt P33991 modified residues and domains). The supplied caption does not identify the antibody epitope, so neither phosphorylation sensitivity nor domain recognition can be assigned to A02301-1 (datasheet A02301-1). Treat changes in nuclear intensity as staining observations rather than evidence of a particular modification (UniProt P33991 modified residues; standard IHC interpretation). If epitope dependence matters, obtain the antibody's epitope information and validate the proposed comparison experimentally (standard IHC practice).
How can I assess MCM4 in a multiplex IF experiment?
Plan IF as a separate assay: the supplied A02301-1 tissue example documents chromogenic staining of paraffin sections, without stating fixation conditions or an IF workflow (datasheet A02301-1). Pair nuclear MCM4 with a lineage marker for the cell population being assessed; HPA reports high MCM4 staining in bone marrow hematopoietic cells, among other populations (HPA tissue IHC). Choose spectrally separated fluorophores and test unstained tissue for autofluorescence before assigning a channel to faint nuclear signal (standard IF practice). Because MCM4 is nuclear and has no transmembrane segment, establish permeabilisation that gives antibodies access to the nucleus in the IF specimen (UniProt P33991 localisation and topology; standard IF practice). Include single-colour and secondary-only controls when assessing multiplex bleed-through and background (standard IF practice).
How do I reduce diffuse colour while preserving nuclear MCM4 signal?
First compare nuclear staining with a section processed without primary antibody to assess detection-system background (standard IHC practice; UniProt P33991 localisation). The documented paraffin-section workflow blocked with 10% goat serum, used 2 µg/mL primary antibody overnight at 4°C, and developed with DAB (datasheet A02301-1). If background persists, check blocking, wash stringency and primary concentration while keeping retrieval and DAB development consistent across comparison sections (standard IHC practice). Include an endogenous peroxidase block where appropriate for a peroxidase-based workflow; this is a general IHC step, not evidence specific to MCM4 (standard IHC practice). Judge improvements by nuclear contrast and retained morphology, not by lower overall colour alone (HPA tissue IHC; standard IHC practice).
What should I measure when comparing MCM4 staining between sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the cell population and tissue region before scoring, then measure the percentage of nuclei above a consistent positivity threshold (standard IHC practice; HPA tissue IHC). For graded nuclear intensity, an H-score combines percentages at intensity grades 0–3 into a score from 0–300 (standard IHC practice). If spatial distribution matters, report positive nuclei per mm² of viable, evaluable tissue alongside the positive fraction (standard IHC practice). Normalise counts to all evaluable nuclei in the same defined population, and exclude folds, necrosis and poorly preserved areas consistently (standard IHC practice). Keep retrieval, detection, imaging and threshold settings comparable across groups because HPA describes variable nuclear expression (datasheet A02301-1; HPA tissue IHC; standard IHC practice).
When is MCM4 staining likely to be artefactual?
A credible result shows interpretable nuclear staining in preserved cells, consistent with MCM4's nuclear and chromosomal localisation (UniProt P33991 localisation; HPA tissue IHC). HPA reports high staining in appendix germinal center cells and bone marrow hematopoietic cells, but low staining in smooth muscle cells and liver cholangiocytes; interpret each cell population separately (HPA tissue IHC). Diffuse cytoplasmic colour, section-edge concentration or staining restricted to necrotic areas should prompt review of processing and background controls (UniProt P33991 localisation; standard IHC practice). Check a no-primary control for endogenous enzyme or detection-system colour before accepting weak signal (standard IHC practice). Treat staining as MCM4 protein distribution, rather than direct proof that an individual cell is actively replicating DNA (UniProt P33991 function; standard IHC interpretation).
Boster reagents
Best MCM4 / DNA replication licensing factor MCM4 IHC Antibodies
Anti-MCM4 IHC images cover human, mouse and rat paraffin sections; IF/ICC imaging covers A431 cells (catalog image captions).
Real IHC data
Anti-MCM4 Antibody ®
Cat # A02301-1
Real IHC data
Anti-MCM4 Rabbit Monoclonal Antibody
Cat # M02301
A02301-1 has IHC images from mouse and rat colon and human breast cancer and gallbladder adenocarcinoma, plus an IF/ICC image from A431 cells (A02301-1 image captions). M02301 has IHC images from human colorectal adenocarcinoma and spleen (M02301 image captions).
Which to pick: For paraffin-section IHC, either antibody has its own image: A02301-1 used EDTA retrieval at pH 8.0 and 2 μg/ml primary antibody in mouse colon, while monoclonal M02301 used EDTA retrieval at pH 8.0 and 1:50 in human colorectal adenocarcinoma (respective IHC image captions). Choose A02301-1 for IF/ICC because its application list includes both and its A431 image uses 5 μg/ml; M02301 lists neither IF nor ICC (catalog applications; A02301-1 IF image caption). A02301-1 also lists human, mouse and rat reactivity, versus human and mouse for M02301; the fixative is unreported in their paraffin-section captions (catalog reactivity; respective IHC image captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P33991 (MCM4_HUMAN, DNA replication licensing factor MCM4).
- Human Protein Atlas. MCM4 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. MCM4 subcellular location (ICC-IF): Localized to the nucleoplasm..
- Human Protein Atlas. MCM4 antibody validation summary (3 antibodies).
- MCM4 expression is associated with high-grade histology, tumor progression and poor prognosis in urothelial carcinoma. Diagnostic pathology 2023 — PMC10515259.
- Minichromosome maintenance 4 is associated with poor survival and stemness of patients with pancreatic cancer. Medical molecular morphology 2026 — PMC12967608.
- MCM4 and MCM7, potential novel proliferation markers, significantly correlated with Ki-67, Bmi1, and cyclin E expression in esophageal adenocarcinoma, squamous cell carcinoma, and precancerous lesions. Human pathology 2016 — PMC5250507.
- Molecular Signature of Small Cell Lung Cancer after Treatment Failure: The MCM Complex as Therapeutic Target. Cancers 2021 — PMC7998124.
- PubMed PMID:7601140 — UniProt-cited evidence.
- PubMed PMID:15489334 — UniProt-cited evidence.
- PubMed PMID:9465298 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for MCM4 (DNA replication licensing factor MCM4). Expected localisation Variable nuclear staining across tissues (HPA tissue IHC). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A02301-1). Validated IHC antibody: A02301-1 at 2-5μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Appendix (Germinal center cells); negative None in HPA (detected in all 45 tissues); use no-primary + isotype controls. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded mouse colon tissue; fixative not specified (datasheet A02301-1); 2. Fixation: Image fixative and duration unreported (datasheet A02301-1); verify before use.; 3. Sectioning: 4–5 µm sections on charged slides (standard); 4. Deparaffinisation: Xylene, graded ethanol series to water (standard); 5. Antigen retrieval: Heat retrieval: EDTA pH 8.0 (datasheet A02301-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A02301-1); 8. Primary antibody: Rabbit anti-MCM4, 2-5μg/ml (datasheet A02301-1); 9. Primary incubation: Overnight at 4 °C (datasheet A02301-1). Watch for: Fixation: Keep paraffin-section fixation consistent across samples (standard IHC practice; not target-specific); Caveat: Chromatin association changes as replication proceeds (UniProt); Isoform / epitope: No annotated isoforms; mature chain spans residues 2–863 (UniProt); Regulation: Nuclear expression varies across tissues (HPA tissue IHC). Evidence: UniProt P33991, HPA tissue IHC · Enhanced, HPA ICC-IF · nucleoplasm., Datasheet A02301-1, PMC10515259, PMC12967608. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/MCM4/immunohistochemistry-ihc-guide.