DAZL / Deleted in azoospermia-like · IHC design guide

Design Immunohistochemistry for DAZL

Plan chromogenic DAZL IHC using testis pachytene spermatocytes as a positive reference (HPA tissue IHC). The catalog antibody's IHC range is 0.5–1 μg/mL (datasheet A02069-2); interpret compartmental staining in light of DAZL's developmental shift from nuclear to cytoplasmic localisation (UniProt).

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

Immunohistochemistry protocol sheet for DAZL (IHC for DAZL): expected localisation Predominantly cytoplasmic; nuclear earlier in germ-cell development (UniProt), antibody A02069-2, validated IHC image, and IHC protocol steps — Printable **DAZL** IHC protocol sheet — expected localisation Predominantly cytoplasmic; nuclear earlier in germ-cell development (UniProt), antibody A02069-2, controls and protocol steps. Open the full DAZL IHC guide →

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DAZL 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	Predominantly cytoplasmic; nuclear earlier in germ-cell development (UniProt)
	Staining pattern	High in pachytene spermatocytes; compartment unreported (HPA tissue IHC)
	Antigen retrieval	EDTA pH 8.0 HIER, heat-mediated (datasheet A02069-2)
	Positive control ⓘ	Testis
	Negative control ⓘ	Adipose tissue+4 more · see all

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	Developmental stage can shift nuclear versus cytoplasmic localisation (UniProt)
	Regulation	Testis-specific expression (UniProt)
	Isoform / epitope	2 isoforms; epitope differences unreported (UniProt)

Section 1

Recommended DAZL IHC & IF Protocols

The catalog antibody protocol uses EDTA retrieval (datasheet A02069-2); the published chromogenic IHC protocol below stained human glioblastoma tissue (PMC7368788).

Recommended immunohistochemistry (IHC-P) protocol parameters
Sample	Paraffin-embedded human testies cancer tissue; fixative not specified (datasheet A02069-2)
Fixation	Image fixative and duration unreported (datasheet A02069-2); 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 A02069-2); 20 min, 95–100 °C (standard)
Peroxidase block	3% H2O2, 10 min, room temperature (standard)
Blocking	10% goat serum (datasheet A02069-2)
Primary antibody	Rabbit anti-DAZL, 0.5-1μg/ml (datasheet A02069-2)
Primary incubation	Overnight at 4 °C (datasheet A02069-2)
Detection	Streptavidin-biotin complex (SABC), DAB chromogen (datasheet A02069-2)
Counterstain	Hematoxylin, blue, dehydrate and mount (standard)
Expected result	DAZL-positive staining in pachytene spermatocytes of testis (HPA tissue IHC: High). HPA tissue profile: High expression in testis. No signal in the no-primary control.

💡Decision noteStart with heat-mediated EDTA, pH 8.0 (datasheet A02069-2). If optimizing retrieval, the published protocol used citrate buffer, pH 6.0 (PMC7368788).

Section 2

What Is the Expected DAZL Staining Pattern?

DAZL staining should center on testicular germ cells, with high signal in pachytene spermatocytes (HPA: High in pachytene spermatocytes; tissue IHC reliability Enhanced). Expect predominantly cytoplasmic staining, while nuclear localization can occur earlier in germ cell development (UniProt Q92904: subcellular location). DAZL has no transmembrane segment (UniProt Q92904: topology).

What am I looking at on my slide?
Pachytene spermatocytes stain strongly; nearby cells show less or no signal.	This matches the documented high pachytene spermatocyte signal in testis (HPA: tissue IHC, Enhanced reliability). Judge cell identity alongside staining intensity: HPA describes a cell-specific pattern, not uniform staining across the section.
Germ cell staining is cytoplasmic, with some nuclear staining in earlier cells.	A predominantly cytoplasmic pattern fits DAZL localization; nuclear localization is also reported during earlier germ cell development (UniProt Q92904: subcellular location). Nuclear signal alone is therefore insufficient to call a slide artefactual without considering cell stage.
The strongest signal outlines membranes or fills extracellular spaces.	That distribution conflicts with the reported cytoplasmic and nuclear locations and the absence of a transmembrane segment (UniProt Q92904: subcellular location; topology). Check detection background and tissue morphology before interpreting the signal as DAZL.
Adipocytes, glandular cells or other expected negative cells stain strongly.	This conflicts with the listed examples of cells in which DAZL was not detected (HPA: adipose tissue adipocytes; adrenal and appendix glandular cells). Cross-reactivity or endogenous detection activity are possible explanations; the pattern alone cannot distinguish them.
Pachytene spermatocytes show no convincing signal.	This conflicts with the expected high testis signal (HPA: pachytene spermatocytes). First check that the expected cells are present and identifiable; an absent signal can also reflect a failed staining workflow or an antibody that has not performed in this preparation.

💡Expected DAZL appearanceCall a section positive when identifiable pachytene spermatocytes show high, chiefly cytoplasmic signal (HPA: High in pachytene spermatocytes; UniProt Q92904: predominantly cytoplasmic); membrane or widespread somatic staining is suspect (UniProt Q92904: topology; HPA: listed negative cells).

How each factor affects the staining
Tissue and cell selection	Testis is the strongest documented tissue choice, with high staining in pachytene spermatocytes (HPA: tissue IHC). Adipose tissue adipocytes and adrenal glandular cells are documented negative examples (HPA: Not detected); interpret controls at the stated cell level.
Germ cell stage and compartment	DAZL is predominantly cytoplasmic, with nuclear localization reported in earlier germ cells and cytoplasmic localization later (UniProt Q92904: subcellular location). A single compartment rule applied to every germ cell stage would overstate the evidence.
Protein topology and processing	DAZL has no transmembrane segment, signal peptide or propeptide (UniProt Q92904: topology; processing). These annotations support intracellular interpretation; they do not identify an antibody epitope or establish any antigen retrieval requirement.
Antibody validation	HPA reports Enhanced IHC status for HPA019777 and Supported IHC status for HPA047113 (HPA: antibody validation). These are antibody-specific assessments; they do not establish the performance of an unspecified catalog antibody in a new laboratory workflow.
Isoforms and epitope knowledge	UniProt lists 2 DAZL isoforms and an RRM at residues 40–115 plus a DAZ region at 167–190 (UniProt Q92904: isoforms; domains). No antibody epitope is supplied, so isoform detection cannot be inferred from these annotations.

Why is my staining missing, weak or wrong?
Situation	Likely cause	Next action
No signal in a testis section containing pachytene spermatocytes.	The result disagrees with the documented high cell-level signal (HPA: pachytene spermatocytes), but the staining result alone does not identify which workflow step failed.	Verify tissue morphology and cell identification, then check primary antibody application, chromogen development and the run controls. Review antigen retrieval using the antibody's validated IHC instructions; no DAZL-specific retrieval condition is supplied.
Diffuse haze obscures germ cell boundaries.	Nonspecific antibody binding or background from the detection system are general IHC possibilities; HPA's Enhanced tissue profile does not explain background in this particular run (HPA: tissue IHC reliability Enhanced).	Compare with a primary-antibody omission control. Review blocking, washes and antibody concentration using the chosen antibody's instructions; retain settings that reveal the expected cell-level pattern without diffuse staining (HPA: pachytene spermatocytes, High).
Signal is strongest at membranes or outside cells.	This is inconsistent with reported cytoplasmic and nuclear DAZL and its lack of a transmembrane segment (UniProt Q92904: subcellular location; topology).	Check morphology, counterstain alignment and the detection control. Reassess the primary antibody result against intracellular staining in identifiable germ cells before scoring the peripheral signal as positive.
Strong staining appears in a documented negative cell type.	DAZL was not detected in adipose tissue adipocytes or adrenal glandular cells in the supplied profile (HPA: tissue IHC). Cross-reactivity and endogenous detection activity are possible, not proven, causes.	Compare a primary-antibody omission control and, for enzyme-based detection, check the relevant endogenous activity control. Score the unexpected cells separately from pachytene spermatocytes rather than treating all brown signal as DAZL.
A nuclear signal prompts concern despite otherwise plausible germ cell staining.	UniProt reports nuclear DAZL in earlier germ cell development and predominantly cytoplasmic localization overall (UniProt Q92904: subcellular location). The compartment needs interpretation with cell identity and stage.	Confirm which germ cells carry the nuclear signal and whether pachytene spermatocytes show the expected strong staining (HPA: pachytene spermatocytes, High). Investigate nuclear staining in unrelated cells against the negative controls.
Q: Can IF/ICC establish the expected DAZL compartment here?	HPA provides no main ICC-IF location and lists no cell lines with ICC-IF images for DAZL (HPA: subcellular record). UniProt reports cytoplasmic and nuclear localization (UniProt Q92904: subcellular location).	A: Use UniProt localization as biological context, but do not claim an HPA-validated IF pattern or transfer the IHC result into an IF protocol (HPA: subcellular record; tissue IHC). Consult the separate IF/ICC guide for that application.

Source: UniProt Q92904 Human Protein Atlas tissue Human Protein Atlas subcellular

Experiment evidence

IHC & IF images showing DAZL staining

IHC analysis of DAZL using anti-DAZL antibody (A02069-2). DAZL was detected in paraffin-embedded section of human testies cancer tissue. Heat mediated antigen retrieval was performed in EDTA buffer (pH8.0, epitope retrieval solution). The tissue section was blocked with 10% goat serum. The tissue section was then incubated with 1μg/ml rabbit anti-DAZL Antibody (A02069-2) overnight at 4°C. Biotinylated goat anti-rabbit IgG was used as secondary antibody and incubated for 30 minutes at 37°C. The tissue section was developed using Strepavidin-Biotin-Complex (SABC) (Catalog # SA1022) with DAB as the chromogen.

A02069-2 · IHCIHC analysis of DAZL using anti-DAZL antibody (A02069-2). DAZL was detected in paraffin-embedded section of human testies cancer tissue. Hea

IHC analysis of DAZL using anti-DAZL antibody (A02069-2). DAZL was detected in paraffin-embedded section of mouse testies cancer tissue. Heat mediated antigen retrieval was performed in EDTA buffer (pH8.0, epitope retrieval solution). The tissue section was blocked with 10% goat serum. The tissue section was then incubated with 1μg/ml rabbit anti-DAZL Antibody (A02069-2) overnight at 4°C. Biotinylated goat anti-rabbit IgG was used as secondary antibody and incubated for 30 minutes at 37°C. The tissue section was developed using Strepavidin-Biotin-Complex (SABC) (Catalog # SA1022) with DAB as the chromogen.

A02069-2 · IHCIHC analysis of DAZL using anti-DAZL antibody (A02069-2). DAZL was detected in paraffin-embedded section of mouse testies cancer tissue. Hea

HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000092345-DAZL/tissue/cerebral+cortex#imid_21043507

HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000092345-DAZL/tissue/colon#imid_21043441

HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000092345-DAZL/tissue/liver#imid_21043434

HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000092345-DAZL/tissue/kidney#imid_21043443

← swipe / scroll for more images →

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

Sample controls for DAZL IHC & IF

🧪Run testis first and look for DAZL staining in pachytene spermatocytes (HPA: High in pachytene spermatocytes). Use adipose tissue as the negative tissue (HPA: Not detected in adipocytes); on the testis slide, use morphologically identifiable unstained somatic cells as internal background comparators, without assuming every non-pachytene cell is negative (HPA: positive row specifies pachytene spermatocytes).

Positive control tissue: Testis (Pachytene spermatocytes, HPA High)

Negative control tissue: Adipose tissue (HPA Not detected)

ICC-IF cell lines (HPA subcellular resource): HPA carries no ICC-IF cell line for DAZL; derive a cell-line control from the positive tissue's cell type (Pachytene spermatocytes) and confirm it by RNA or western blot first.

Technical controls: Include a no-primary, secondary-only control; a concentration-matched rabbit IgG isotype control matched to the primary’s format; and DAZL knockout tissue or cognate peptide competition if available (catalog caption: rabbit anti-DAZL at 1 μg/ml; standard IHC control practice). Quench endogenous peroxidase and check for endogenous biotin background in testis when using the caption’s biotin-based DAB detection (catalog caption: biotinylated secondary, streptavidin-biotin complex and DAB; standard IHC practice).

⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the exact selected-SKU tissue-IHC caption does not report a fixative (catalog caption: fixative not stated). The paraffin-section example uses heat retrieval in EDTA at pH 8.0, but a retrieval requirement has not been established by comparison; the supplied evidence also does not establish that frozen sections or IF are easier (catalog caption: paraffin IHC with EDTA retrieval; HPA subcellular: no ICC-IF image cell lines). In testis, developmental changes between nuclear and cytoplasmic localization can complicate compartment-based scoring (UniProt Q92904: nuclear in spermatogonia until near the end of meiotic prophase, then cytoplasmic).

HPA tissue IHC evidence for DAZL

Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — High 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
Testis	Pachytene spermatocytes	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 →
Appendix	Glandular cells	Not detected	Protein (IHC)	HPA →
Bone marrow	Hematopoietic cells	Not detected	Protein (IHC)	HPA →
Breast	Adipocytes	Not detected	Protein (IHC)	HPA →

Section 3

Advanced DAZL IHC Tips

Use the catalog antibody’s paraffin section workflow as a starting point, then assess staining against DAZL’s reported testis expression and changing subcellular location.

What retrieval should I start with for DAZL in paraffin sections?

Start with heat-mediated retrieval in EDTA pH 8.0 for paraffin sections (datasheet A02069-2). The selected image used this retrieval before an overnight 4°C incubation with 1 μg/mL primary antibody (datasheet A02069-2). If staining is weak, vary heating time in small increments while keeping the buffer and antibody concentration fixed, and inspect tissue integrity after each run (standard IHC practice). Compare each run with testis containing pachytene spermatocytes, where strong staining is reported (HPA: High in pachytene spermatocytes). Include a section processed without primary antibody to identify detection-system signal (standard IHC practice).

How should I troubleshoot fixation-related loss of DAZL staining?

The selected image documents a paraffin-embedded section, but its fixative is unreported; DAZL-specific fixation sensitivity is therefore unknown (datasheet A02069-2). Record the fixative, fixation duration and processing history for each specimen before comparing staining intensity (standard IHC practice). For routine formalin-fixed material, compare a consistently processed positive control alongside each batch and avoid attributing a weak result to fixation alone (standard IHC practice). Keep retrieval at EDTA pH 8.0 and the starting primary concentration at 1 μg/mL while assessing processing differences (datasheet A02069-2). If controls also weaken, check section adhesion, retrieval consistency and detection reagents before interpreting specimen biology (standard IHC practice).

Should DAZL staining be nuclear or cytoplasmic in testis sections?

Assess compartment and cell stage together: DAZL is predominantly cytoplasmic, with nuclear localisation in spermatogonia until near the end of meiotic prophase and cytoplasmic localisation thereafter (UniProt Q92904). Strong staining in pachytene spermatocytes is a useful tissue reference (HPA: High in pachytene spermatocytes). Use a nuclear counterstain and score nuclear and cytoplasmic signal separately in morphologically identified germ cells (standard IHC practice). The selected chromogenic image used DAB after EDTA pH 8.0 retrieval, but does not establish a universal compartment pattern for every specimen (datasheet A02069-2). Diffuse staining across unrelated cell types warrants a background check before assignment to DAZL (HPA: tissue enriched in testis; standard IHC practice).

Can this stain distinguish DAZL isoforms or reveal epitope masking?

DAZL has 2 reported isoforms, while the supplied antibody caption does not map its epitope or establish isoform selectivity (UniProt Q92904; datasheet A02069-2). Its RRM spans residues 40–115, and its DAZ domain spans 167–190; these positions do not locate the antibody-binding site (UniProt Q92904). A reported phosphotyrosine at residue 276 likewise does not demonstrate altered IHC recognition (UniProt Q92904). If an isoform-specific conclusion matters, obtain epitope information and assess it against isoform sequences before interpreting staining differences (standard antibody validation practice). Until then, report the result as DAZL immunoreactivity under the tested retrieval and detection conditions (datasheet A02069-2).

How can I adapt the DAZL IHC result to multiplex immunofluorescence?

Treat IF as a separate assay: the selected antibody evidence documents chromogenic staining of paraffin sections, and no ICC/IF images are supplied here (datasheet A02069-2; HPA subcellular record). Pair DAZL with a validated marker for the germ-cell stage being examined, using testis morphology and the reported pachytene spermatocyte signal as context (HPA: High in pachytene spermatocytes; standard IF practice). Select spectrally separated fluorophores after checking tissue autofluorescence, and include single-channel and secondary-only controls (standard IF practice). Because DAZL has no transmembrane segment and occupies cytoplasmic and nuclear compartments, optimise permeabilisation for intracellular epitope access without assuming its unmapped antibody epitope lies in either compartment (UniProt Q92904; standard IF practice).

What should I check when DAZL DAB staining appears widespread?

Start by comparing the distribution with testis germ cells: DAZL is reported as testis specific, and HPA reports high staining in pachytene spermatocytes (UniProt Q92904; HPA: High in pachytene spermatocytes). Widespread signal in unrelated structures should prompt primary-omission and secondary-reagent controls, plus inspection for endogenous peroxidase activity and nonspecific biotin-based detection (standard IHC practice). The selected image used a biotinylated secondary, avidin-biotin detection and DAB, making those controls relevant to that workflow (datasheet A02069-2). Check blocking and antibody concentration before increasing retrieval intensity; the image used 10% goat serum and 1 μg/mL primary antibody (datasheet A02069-2). Compare staining within intact tissue and at section edges separately (standard IHC practice).

How should I quantify DAZL staining across testis sections? ⚠ ANSWER MARKED FOR VERIFICATION

Define the germ-cell population and compartment before scoring, because DAZL localisation changes with developmental stage (UniProt Q92904). Report the percentage of positive cells and an intensity-based H-score within each defined population, using the same scoring thresholds across specimens (standard IHC practice). If counting stained cells per mm², normalise to evaluable tissue area and report cell composition so changes in germ-cell abundance are distinguishable from staining changes (standard IHC practice). Keep retrieval and primary incubation consistent with the starting EDTA pH 8.0 and 1 μg/mL workflow during comparisons (datasheet A02069-2). Exclude folds, necrotic regions and tissue edges using predefined rules (standard IHC practice).

How do I distinguish true DAZL staining from artefact?

A credible positive aligns with germ-cell morphology and the reported strong signal in pachytene spermatocytes (HPA: High in pachytene spermatocytes). Interpret nuclear versus cytoplasmic staining by cell stage, since DAZL is nuclear in spermatogonia until near the end of meiotic prophase and predominantly cytoplasmic thereafter (UniProt Q92904). Signal concentrated at cut edges, in necrotic material or across unrelated cells deserves repeat assessment with primary-omission and detection controls (standard IHC practice). Because the selected workflow used biotin-based detection and DAB, check endogenous enzyme or detection-system signal before calling unexpected staining positive (datasheet A02069-2; standard IHC practice). Corroborate ambiguous results with an independently validated assay (standard antibody validation practice).

Boster reagents

Best DAZL / Deleted in azoospermia-like IHC Antibodies

The IHC-validated DAZL antibody has real staining images from human, mouse, and rat paraffin-embedded testis cancer sections (catalog IHC image captions).

Real IHC data

Anti-DAZL ® Antibody

Cat # A02069-2

View product →

A02069-2 is the sole card and has IHC images from human, mouse, and rat paraffin-embedded testis cancer sections (catalog IHC image captions). Its listed applications include IHC, while IF/ICC validation and IF images are absent from the payload (catalog applications; catalog IF image alts).

Which to pick: For tissue IHC, choose A02069-2: its own images show staining of paraffin-embedded sections, and its listed IHC concentration is 0.5–1 μg/ml (catalog IHC image captions; catalog IHC dilution). For IF/ICC? No SKU in this payload has IF validation or an IF figure; use the separate IF/ICC guide for that application (catalog applications; catalog IF image alts). For cross-species IHC, A02069-2 has human, mouse, and rat reactivity and corresponding IHC images; the captions do not report the fixative (catalog reactivity; catalog IHC image captions).

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

References

UniProt Consortium. UniProt entry Q92904 (DAZL_HUMAN, Deleted in azoospermia-like).
Human Protein Atlas. DAZL tissue IHC expression (reliability: Enhanced).
Human Protein Atlas. DAZL subcellular location (ICC-IF): Highest expression in HAP1: 17.2 nTPM.
Human Protein Atlas. DAZL antibody validation summary (2 antibodies).
Suppressing Dazl modulates tumorigenicity and stemness in human glioblastoma cells. BMC cancer 2020 — PMC7368788.
RNA immunoprecipitation identifies novel targets of DAZL in human foetal ovary. Molecular human reproduction 2017 — PMC5943682.
GDF9 is transiently expressed in oocytes before follicle formation in the human fetal ovary and is regulated by a novel NOBOX transcript. PloS one 2015 — PMC4366263.
Single-cell RNA sequencing of mitotic-arrested prospermatogonia with DAZL::GFP chickens and revealing unique epigenetic reprogramming of chickens. Journal of animal science and biotechnology 2022 — PMC9169296.
PubMed PMID:8896558 — UniProt-cited evidence.
PubMed PMID:8968755 — UniProt-cited evidence.
PubMed PMID:8968756 — UniProt-cited evidence.