This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
MAP4 / Microtubule-associated protein 4 · IHC design guide
Design Immunohistochemistry for MAP4
Plan chromogenic paraffin IHC for MAP4 using its general cytoplasmic tissue pattern (HPA tissue IHC). Lung endothelial cells show high staining, while adipocytes are undetected; use these as cell-specific references when scoring (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
MAP4 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 | Cytoplasm (HPA tissue IHC); cytoskeleton/MTOC (UniProt) | |
| Staining pattern | General cytoplasmic staining; distinct in nerves and endothelium (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet A00948-2) | |
| Positive control | Caudate+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 paraffin sections (standard IHC practice; not target-specific) | |
| Caveat | Microtubule polyglutamylation inhibits MAP4 recruitment (UniProt) | |
| Regulation | Expression regulation not annotated (UniProt) | |
| Isoform / epitope | 7 isoforms; antibody epitope coverage needs validation (UniProt) |
Section 1
Recommended MAP4 IHC & IF Protocols
The catalog antibody protocol (datasheet A00948-2) is followed by four published MAP4 IHC protocols (PMC10858930; PMC5878896; PMC6435630; PMC10054043).
| Sample | Paraffin-embedded human ovarian cancer tissue; fixative not specified (datasheet A00948-2) |
| Fixation | Image fixative and duration unreported (datasheet A00948-2); 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 A00948-2); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A00948-2) |
| Primary antibody | Rabbit anti-MAP4, 1:50 recommended; image 1:100 (datasheet A00948-2) |
| Primary incubation | Overnight at 4 °C (datasheet A00948-2) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet A00948-2) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | MAP4-positive staining in glial cells of caudate (HPA tissue IHC: High). HPA tissue profile: General cytoplasmic expression. Distinct expression in peripheral nerves and endothelial cells. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA retrieval at pH 8.0 (datasheet A00948-2); two lung adenocarcinoma protocols also used EDTA at pH 8 (PMC10858930; PMC5878896).
Section 2
What Is the Expected MAP4 Staining Pattern?
MAP4 is a non-neuronal microtubule-associated protein that localizes to the cytoplasm, cytoskeleton and microtubule-organizing center; it has no transmembrane segment (UniProt P27816). In tissue IHC, expect general cytoplasmic staining, with distinct staining in peripheral nerves and endothelial cells (HPA tissue IHC). HPA rates the tissue pattern Enhanced, while noting medium consistency between antibody staining and RNA expression (HPA tissue IHC).
| Cytoplasmic staining in lung endothelial cells, caudate glial cells or endometrial stromal cells. | This fits HPA's High staining in those cell populations and MAP4's cytoskeletal location (HPA tissue IHC; UniProt P27816). Judge the named cells within their tissue context; a positive field alone does not establish that every stained cell is a specific positive. |
| Predominantly nuclear staining, with little cytoplasmic staining in an expected-positive cell population. | A predominantly nuclear result conflicts with the supplied cytoplasmic and cytoskeletal localization (UniProt P27816; HPA tissue IHC). Check antibody specificity and detection controls before scoring it as MAP4; nuclear color alone is insufficient evidence of a true positive (standard IHC practice). |
| Strong staining in adipocytes or bone-marrow hematopoietic cells, especially without staining in an expected-positive control. | HPA reports MAP4 as Not detected in these specified cell populations, so review cell identification and possible cross-reactivity or endogenous detection activity (HPA tissue IHC; standard IHC practice). A negative HPA observation is a comparator, not proof that every specimen must be negative. |
| Diffuse color across cells and extracellular spaces, with poor distinction between cytoplasm and background. | This does not match HPA's cell-resolved tissue pattern (HPA tissue IHC). Run an appropriate detection-only control and review blocking, washing and chromogen development; diffuse deposit may reflect assay background rather than MAP4 localization (standard IHC practice). |
| No staining in lung endothelial cells or another documented High cell population. | The absent expected signal makes that run difficult to interpret (HPA tissue IHC). First check the positive-control section, tissue preservation, retrieval conditions, antibody dilution and detection reagents (standard IHC practice); the supplied sources establish no MAP4-specific fixation sensitivity. |
💡Expected MAP4 appearanceCall a section positive when identifiable expected cells show discernible cytoplasmic staining—for example, High staining in lung endothelial cells or caudate glia (HPA tissue IHC; UniProt P27816); predominant nuclear color or indiscriminate extracellular deposit is suspect (standard IHC practice).
| Cell population and tissue context | HPA reports High staining in Bergmann glia, cervical squamous epithelium, kidney Bowman's capsule and lung endothelium, but Not detected staining in adipocytes and several other specified populations (HPA tissue IHC). Compare like cells within like tissues; do not score a whole organ as uniformly positive or negative. |
| Strength of the tissue evidence | The HPA tissue profile is rated Enhanced, with medium consistency between antibody staining and RNA expression; both listed antibodies have Enhanced IHC validation (HPA tissue IHC; HPA antibodies). These ratings support the reported pattern but do not validate a different antibody or every individual specimen. |
| Intracellular distribution | UniProt places MAP4 in the cytoskeleton and microtubule-organizing center; HPA describes general cytoplasmic tissue staining (UniProt P27816; HPA tissue IHC). Interpret compartment at the resolution of chromogenic paraffin IHC; fine microtubule structures may not be individually resolved (standard IHC practice). |
| Isoform and epitope coverage | UniProt lists seven MAP4 isoforms (UniProt P27816). If an antibody recognizes an isoform-dependent epitope, coverage could vary; no epitope map or isoform-specific tissue pattern is supplied, so the sources cannot assign a particular staining difference to isoform choice. |
| IF/ICC Q: What localization is reported? | A: HPA supports microtubules, primary cilium and basal body in ICC-IF; it labels plasma membrane and cytosol uncertain, and also reports approved acrosome and equatorial-segment locations (HPA subcellular). This cell-imaging evidence helps interpret IF/ICC but does not establish those fine structures in chromogenic tissue IHC. |
| Situation | Likely cause | Next action |
|---|---|---|
| Expected-positive tissue is blank. | The assay may have missed antigen or failed at detection; HPA reports High staining in several defined cell populations (HPA tissue IHC; standard IHC practice). | Check an HPA-documented positive cell population on the same run, then review retrieval, antibody dilution, reagent activity and detection timing (HPA tissue IHC; standard IHC practice). No MAP4-specific retrieval condition is supplied. |
| The section is uniformly brown. | Excess detection activity, inadequate washing or prolonged chromogen development can obscure cell-specific staining (standard IHC practice). | Inspect a detection-only control; adjust blocking, washing or development using standard IHC optimization, then reassess cytoplasmic staining in named positive cells (standard IHC practice; HPA tissue IHC). |
| Nuclei dominate the signal. | Predominantly nuclear color does not fit MAP4's reported cytoskeletal location (UniProt P27816). | Compare with a known-positive cell population and appropriate negative detection control; review specificity before assigning nuclear color to MAP4 (HPA tissue IHC; standard IHC practice). |
| Adipocytes or marrow hematopoietic cells stain strongly. | That result differs from HPA's Not detected observations for those cells; cross-reactivity or endogenous activity is possible (HPA tissue IHC; standard IHC practice). | Confirm cell identity and compare a detection-only control with a documented positive population in the same run (HPA tissue IHC; standard IHC practice). Investigate the discrepancy before changing the expected pattern. |
| A reported positive tissue looks patchy. | HPA reports staining for named cell populations, not uniform positivity throughout an organ; its tissue profile has medium antibody–RNA consistency (HPA tissue IHC). | Score identifiable cells separately, compare multiple fields and record which compartments carry signal (HPA tissue IHC; standard IHC practice). Do not turn an unstained neighboring cell into a failed control. |
| The IF/ICC image and tissue IHC slide appear different. | HPA's supported cilium and microtubule assignments come from ICC-IF, whereas its tissue IHC profile describes broader cytoplasmic staining (HPA subcellular; HPA tissue IHC). | Interpret each image at its assay's spatial resolution; use the tissue IHC profile for paraffin-section scoring and consult the separate IF/ICC guide for IF workflow (HPA tissue IHC; standard IHC practice). |
Experiment evidence
IHC & IF images showing MAP4 staining
A00948-2 · IHCIHC analysis of MAP4 using anti-MAP4 antibody (A00948-2). MAP4 was detected in a paraffin-embedded section of human ovarian cancer tissue. H
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000047849-MAP4/tissue/cerebral+cortex#imid_20517347
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000047849-MAP4/tissue/colon#imid_20510057
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000047849-MAP4/tissue/liver#imid_20510066
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000047849-MAP4/tissue/kidney#imid_20510075
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA038149; green = MAP4, blue = nucleus, red = microtubules.
HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody HPA038149; green = MAP4, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for MAP4 IHC & IF
🧪Run cervix first: squamous epithelial cells should stain for MAP4 (HPA: High in cervical squamous epithelial cells). Use adipose tissue as the negative comparator (HPA: Not detected in adipocytes); on the cervix slide, use cells without specific chromogen signal as an internal background reference, without assuming that a particular other cell type is MAP4-negative.
Positive control tissue: Caudate (Glial cells, HPA High)
Negative control tissue: Adipose tissue (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show MAP4 in A-431, U-251MG, U2OS, ASC52telo, RPTEC/TERT1, hTERT-RPE1 (serum starved), Sperm, with annotated localisation: Plasma membrane (uncertain), Microtubules (supported), Primary cilium (supported), Cytosol (uncertain) (HPA subcellular).
Technical controls: Include a no-primary, secondary-only control and an irrelevant IgG control matched to the primary antibody’s host and clonality; the caption antibody is rabbit-derived (selected-SKU IHC caption; standard IHC practice). A MAP4 knockout sample is a biological negative control, and endogenous peroxidase should be blocked before HRP/DAB detection (standard IHC practice; selected-SKU IHC caption: HRP/DAB).
⚠️Feasibility: The selected-SKU paraffin-section caption does not report a fixative, and no target-specific fixation window or fixation effect is reported in the supplied evidence (selected-SKU IHC caption). The demonstrated IHC procedure uses heat-mediated retrieval in EDTA at pH 8.0, followed by a 1:100 primary dilution; this shows a workable retrieval condition, not that retrieval is universally required (selected-SKU IHC caption). The supplied evidence does not establish that frozen sections or IF/ICC are easier, or identify a cervix-specific artefact (selected-SKU IHC caption; HPA subcellular ICC-IF record).
HPA tissue IHC evidence for MAP4
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 |
|---|---|---|---|---|
| Caudate | Glial cells | High | Protein (IHC) | HPA → |
| Cerebellum | Bergmann glia - cytoplasm/membrane | High | Protein (IHC) | HPA → |
| Cervix | Squamous epithelial cells | High | Protein (IHC) | HPA → |
| Endometrium | Cells in endometrial stroma | High | Protein (IHC) | HPA → |
| Epididymis | 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 → |
| Adrenal gland | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Bone marrow | Hematopoietic cells | Not detected | Protein (IHC) | HPA → |
| Nasopharynx | Respiratory epithelial cells | Not detected | Protein (IHC) | HPA → |
| Parathyroid gland | Glandular cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced MAP4 IHC Tips
Troubleshoot MAP4 staining in paraffin section chromogenic IHC, using the catalog antibody’s tissue image and independent localisation evidence as reference points.
What retrieval should I try first when MAP4 staining is weak in paraffin sections?
Start with heat mediated retrieval in EDTA pH 8.0 (datasheet A00948-2). The catalog antibody produced MAP4 staining in a paraffin section of human ovarian cancer tissue after that retrieval, followed by 1:100 primary antibody overnight at 4°C (datasheet A00948-2). Keep section thickness, heating, cooling, and detection conditions consistent while comparing retrieval runs, since changing several variables obscures the cause of weak staining (standard IHC practice). If staining remains weak, compare a second retrieval condition on adjacent sections as a fallback, recording its buffer and pH rather than assuming it is equivalent (standard IHC practice). Include a known staining control in each run so retrieval failure can be distinguished from a low expressing region (standard IHC practice).
Could fixation explain weak or uneven MAP4 staining?
The selected tissue image identifies a paraffin section but does not report its fixative, so MAP4 specific fixation sensitivity is unknown (datasheet A00948-2). Record the specimen’s actual fixative, fixation duration, and processing history before comparing staining across blocks, because these variables can alter antigen accessibility in IHC (standard IHC practice). Compare affected sections with a processed control under the same EDTA pH 8.0 retrieval and antibody conditions (datasheet A00948-2; standard IHC practice). If a block stains poorly, assess tissue preservation and staining by an independent control before changing retrieval or primary concentration (standard IHC practice). Do not infer a MAP4 fixation requirement from its cytoskeletal localisation or posttranslational modifications alone (UniProt P27816 localisation and modified residues).
Which staining pattern is plausible for MAP4 in tissue sections?
Expect predominantly cytoplasmic staining in an appropriate cell population, while recognising that chromogenic IHC may not resolve individual microtubules (HPA tissue IHC profile; UniProt P27816 subcellular localisation; standard IHC practice). MAP4 is a nonneuronal microtubule associated protein that promotes microtubule assembly and also localises to the microtubule organising centre (UniProt P27816 function and subcellular localisation). Independent tissue staining reports distinct signal in peripheral nerves and endothelial cells, alongside general cytoplasmic expression (HPA tissue IHC profile). Score cellular distribution separately from intensity so a stained vessel is not mistaken for staining of adjacent parenchyma (HPA tissue IHC profile; standard IHC practice). A predominantly nuclear pattern warrants review of controls, section quality, and the antibody’s expected staining pattern (UniProt P27816 subcellular localisation; standard IHC practice).
How should MAP4 isoforms and epitope uncertainty affect IHC interpretation?
MAP4 has 7 annotated isoforms, while the supplied catalog caption does not define which isoforms its antibody detects (UniProt P27816 isoforms; datasheet A00948-2). Treat an IHC positive cell as MAP4 immunoreactivity rather than evidence for a particular isoform unless epitope mapping or isoform specific validation is available (UniProt P27816 isoforms; standard IHC practice). The record lists 45 modified residues, including phosphoserines, but it does not establish whether any modification changes this antibody’s binding in tissue (UniProt P27816 modified residues). Compare sections under identical retrieval and detection conditions before attributing an intensity difference to splicing or phosphorylation (standard IHC practice). Document the antibody identity and any independently established epitope information when reporting isoform related claims (standard IHC practice).
How can I follow up an IHC pattern with MAP4 immunofluorescence?
Use IF as a separate validation experiment, because the selected antibody evidence describes chromogenic staining of a paraffin tissue section (datasheet A00948-2). Multiplex MAP4 with an independently validated marker for the cell population under examination, such as an endothelial marker when investigating vessel associated staining (HPA tissue IHC profile; standard IF practice). Choose fluorophores in spectral channels that remain distinct from the specimen’s autofluorescence, and include single stain controls to assess bleed through (standard IF practice). For an intracellular MAP4 epitope, optimise permeabilisation after fixation; MAP4 has no annotated transmembrane segment and is associated with cytoplasmic microtubules (UniProt P27816 topology and subcellular localisation; standard IF practice). Check whether the IF distribution agrees with supported microtubule or primary cilium localisation before interpreting fine structures (HPA subcellular profile).
What should I check when MAP4 IHC has diffuse background?
Separate widespread chromogen deposition from cellular MAP4 staining by examining a section processed without primary antibody alongside the test section (standard IHC practice). The selected image used 10% goat serum blocking, 1:100 primary antibody overnight at 4°C, an anti rabbit peroxidase secondary for 30 minutes at 37°C, and DAB development (datasheet A00948-2). If background is high, check blocking, washing, primary concentration, secondary specificity, and DAB development one variable at a time (standard IHC practice). Include a peroxidase blocking step and inspect its control, since endogenous enzyme activity can produce signal in chromogenic IHC (standard IHC practice). Compare suspected background with the expected cellular cytoplasmic distribution, including endothelial cells where present (HPA tissue IHC profile).
How should MAP4 staining be scored across tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the anatomical region and cell population before scoring, because MAP4 tissue staining includes cytoplasmic signal and distinct endothelial cell expression (HPA tissue IHC profile). For cellular comparisons, report the percentage of positive cells and, when intensity matters, an H-score using the same scoring thresholds across sections (standard IHC practice). If the question concerns MAP4 positive structures, report positive cell or structure density per mm² of evaluable tissue instead (standard IHC practice). Normalise to the number of eligible cells or evaluable tissue area, excluding folds, necrosis, and empty regions using a prespecified rule (standard IHC practice). Keep retrieval, detection, counterstain, imaging, and threshold settings consistent, and score endothelial and parenchymal compartments separately when relevant (datasheet A00948-2; HPA tissue IHC profile; standard IHC practice).
How can I distinguish true MAP4 staining from an IHC artefact?
Look for cellular cytoplasmic staining in a plausible population, with endothelial cells and peripheral nerves as useful tissue landmarks where present (HPA tissue IHC profile; UniProt P27816 subcellular localisation). Strong signal confined to nuclei is discordant with the supplied MAP4 localisation evidence and calls for review of antibody and detection controls (UniProt P27816 subcellular localisation; standard IHC practice). Discount staining restricted to section edges, folds, or necrotic regions until it persists in well preserved tissue (standard IHC practice). A no primary control helps identify secondary reagent or endogenous peroxidase signal, while a known staining control helps identify a failed run (standard IHC practice). Interpret weak or absent staining cautiously: the HPA tissue IHC assessment reports Enhanced reliability with medium agreement between staining and RNA expression (HPA tissue IHC reliability).
Boster reagents
Best MAP4 / Microtubule-associated protein 4 IHC Antibodies
A00948-2 has real IHC data from a paraffin-embedded human ovarian cancer section (IHC image caption). IF/ICC is listed for human, mouse, and rat (catalog applications and reactivity).
Real IHC data
Anti-MAP4 Antibody ®
Cat # A00948-2
A00948-2 was shown by IHC in a paraffin-embedded human ovarian cancer section (IHC image caption). Its listed applications include IHC, IF, and ICC for human, mouse, and rat, but no IF image is supplied (catalog applications, reactivity, and IF image alts).
Which to pick: For tissue IHC, choose A00948-2: its image caption documents EDTA retrieval at pH 8.0 and DAB detection in a paraffin-embedded human section; the fixative is unreported (A00948-2 IHC image caption). For IF/ICC, A00948-2 is the listed option, though no IF image or IF dilution is supplied (catalog applications, IF image alts, and dilution fields). For cross-species work, A00948-2 is listed as a rabbit polyclonal antibody reactive with human, mouse, and rat; its pictured IHC evidence is human only (catalog host, dilution_raw, and reactivity; A00948-2 IHC image caption).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P27816 (MAP4_HUMAN, Microtubule-associated protein 4).
- Human Protein Atlas. MAP4 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. MAP4 subcellular location (ICC-IF): Mainly localized to the plasma membrane, cytosol, microtubules and primary cilium. In addition localized to the basal body, acrosome and equatorial segment..
- Human Protein Atlas. MAP4 antibody validation summary (2 antibodies).
- MAP4 acts as an oncogene and prognostic marker and affects radioresistance by mediating epithelial-mesenchymal transition in lung adenocarcinoma. Journal of cancer research and clinical oncology 2024 — PMC10858930.
- Microtubule-Associated Protein 4 Is a Prognostic Factor and Promotes Tumor Progression in Lung Adenocarcinoma. Disease markers 2018 — PMC5878896.
- Expression of Syk and MAP4 proteins in ovarian cancer. Journal of cancer research and clinical oncology 2019 — PMC6435630.
- FBXW7 loss of function promotes esophageal squamous cell carcinoma progression via elevating MAP4 and ERK phosphorylation. Journal of experimental & clinical cancer research : CR 2023 — PMC10054043.
- PubMed PMID:1718985 — UniProt-cited evidence.
- PubMed PMID:7857940 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for MAP4 (Microtubule-associated protein 4). Expected localisation Cytoplasm (HPA tissue IHC); cytoskeleton/MTOC (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet A00948-2). Validated IHC antibody: A00948-2 at 1:50 recommended; image 1:100 (the product's own IHC validation image is shown). Controls (HPA): positive Caudate (Glial cells); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human ovarian cancer tissue; fixative not specified (datasheet A00948-2); 2. Fixation: Image fixative and duration unreported (datasheet A00948-2); 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 A00948-2); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A00948-2); 8. Primary antibody: Rabbit anti-MAP4, 1:50 recommended; image 1:100 (datasheet A00948-2); 9. Primary incubation: Overnight at 4 °C (datasheet A00948-2). Watch for: Fixation: Keep fixation consistent across paraffin sections (standard IHC practice; not target-specific); Caveat: Microtubule polyglutamylation inhibits MAP4 recruitment (UniProt); Isoform / epitope: 7 isoforms; antibody epitope coverage needs validation (UniProt); Regulation: Expression regulation not annotated (UniProt). Evidence: UniProt P27816, HPA tissue IHC · Enhanced, HPA ICC-IF · Mainly localized to the plasma membrane, cytosol, microtubules and…, Datasheet A00948-2, PMC10858930, PMC5878896. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/MAP4/immunohistochemistry-ihc-guide.