CRYAB / Alpha-crystallin B chain · IHC design guide

Design Immunohistochemistry for CRYAB

Plan CRYAB chromogenic IHC in paraffin sections using cytoplasmic staining in cardiomyocytes and glia as a reference (HPA tissue IHC). Start the IHC-validated antibody at 2–5 μg/mL (datasheet A03496-2), and compare staining with appropriate controls (standard IHC practice).

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

Immunohistochemistry protocol sheet for CRYAB (IHC for CRYAB): expected localisation Cytoplasmic staining in a subset of tissues (HPA tissue IHC), antibody A03496-2, validated IHC image, and IHC protocol steps — Printable **CRYAB** IHC protocol sheet — expected localisation Cytoplasmic staining in a subset of tissues (HPA tissue IHC), antibody A03496-2, controls and protocol steps. Open the full CRYAB IHC guide →

Navigate to: Protocols Staining pattern Controls Antibodies

CRYAB Immunohistochemistry Experimental Design Guide

Expected localisation, validated protocols, controls and antibodies — the at-a-glance facts below, then the full design guide.

Must know before staining

	Expected localisation	Cytoplasmic staining in a subset of tissues (HPA tissue IHC)
	Staining pattern	Cardiomyocytes and glia show cytoplasmic staining (HPA tissue IHC)
	Antigen retrieval	EDTA pH 8.0 HIER, heat-mediated (datasheet A03496-2)
	Positive control ⓘ	Caudate+4 more · see all
	Negative control ⓘ	Adrenal gland+4 more · see all

Important caveats

Reasons your staining may differ from the expected pattern.

	Fixation	Keep fixation conditions consistent across sections. (standard IHC practice; not target-specific)
	Caveat	Heat shock may add nuclear signal (UniProt)
	Regulation	Heat shock shifts CRYAB toward the nucleus (UniProt)
	Isoform / epitope	No isoforms; 1–175 chain; no TM epitope split (UniProt)

Section 1

Recommended CRYAB IHC & IF Protocols

The catalog antibody uses EDTA retrieval for IHC-P (datasheet A03496-2). The published protocols cover ovarian cancer FFPE sections (PMC6579977) and frozen human brain sections stained for phospho-CRYAB Ser59 (PMC8963874).

Recommended immunohistochemistry (IHC-P) protocol parameters
Sample	Paraffin-embedded rat brain tissue; fixative not specified (datasheet A03496-2)
Fixation	Image fixative and duration unreported (datasheet A03496-2); 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 A03496-2); 20 min, 95–100 °C (standard)
Peroxidase block	3% H2O2, 10 min, room temperature (standard)
Blocking	10% goat serum (datasheet A03496-2)
Primary antibody	Rabbit anti-CRYAB, 2-5μg/ml (datasheet A03496-2)
Primary incubation	Overnight at 4 °C (datasheet A03496-2)
Detection	Streptavidin-biotin complex (SABC), DAB chromogen (datasheet A03496-2)
Counterstain	Hematoxylin, blue, dehydrate and mount (standard)
Expected result	CRYAB-positive staining in glial cells of caudate (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression in a subset of tissues including heart muscle, brain, thyroid gland, kidney and peripheral nerves. No signal in the no-primary control.

💡Decision noteStart with heat-mediated EDTA, pH 8.0, for the catalog antibody (datasheet A03496-2). The ovarian FFPE protocol instead used citrate, pH 6.0 (PMC6579977).

Section 2

What Is the Expected CRYAB Staining Pattern?

In paraffin section IHC, expect CRYAB chiefly in the cytoplasm of selected cells, including cardiomyocytes, lens fiber cells, glia and cells of Bowman’s capsule (HPA tissue IHC: High). HPA rates the tissue staining reliability Enhanced, with high consistency between antibody staining and RNA expression (HPA tissue IHC). CRYAB has no transmembrane segment; nuclear localization can occur during heat shock (UniProt P02511 topology and subcellular location).

What am I looking at on my slide?
Strong cytoplasmic staining in cardiomyocytes or lens fiber cells, with recognizable cell boundaries.	This fits the reported High staining in both cell populations (HPA tissue IHC: Heart muscle and Eye). Compare cells within the same section before calling weaker neighboring cells positive (general IHC practice).
Cytoplasmic staining in glia, including Bergmann glia, while nearby cells stain differently.	This fits High staining in caudate, cerebral cortex and hippocampal glial cells, and in cerebellar Bergmann glia (HPA tissue IHC). Cell specific staining is more informative than an average intensity across the section (general IHC practice).
Predominantly nuclear staining, or a membrane only pattern, in an otherwise routine IHC section.	Review compartment assignment and controls: HPA describes tissue IHC chiefly as cytoplasmic (HPA tissue IHC). Nuclear CRYAB can occur during heat shock (UniProt P02511); plasma membrane localization comes from ICC-IF and does not establish the dominant paraffin section pattern (HPA subcellular ICC-IF).
Strong signal in cells listed as Not detected, such as adrenal gland glandular cells or bronchial respiratory epithelial cells.	This conflicts with those specific HPA observations (HPA tissue IHC: Adrenal gland and Bronchus). Check a no primary control for endogenous detection activity, then assess nonspecific binding or antibody cross-reactivity (general IHC practice); the tissue name alone is insufficient to judge every cell in it.
Diffuse brown haze across cells and extracellular spaces, or no signal in a known positive cell population.	Haze obscures the cell and compartment pattern used to interpret CRYAB (HPA tissue IHC: cytoplasmic profile). An absent signal in cardiomyocytes or lens fiber cells conflicts with their reported High staining (HPA tissue IHC); either result calls for assay controls before a biological conclusion (general IHC practice).

💡Expected CRYAB appearanceCall the result positive when distinct, often strong cytoplasmic signal marks the expected cells, such as cardiomyocytes or lens fiber cells (HPA tissue IHC: High); uniform haze or strong staining in a listed Not detected cell population is suspect (HPA tissue IHC; general IHC practice).

How each factor affects the staining
Cell population selected for interpretation	HPA reports High staining in cardiomyocytes, lens fiber cells, several glial populations and Bowman’s capsule, but Not detected in selected other cell populations (HPA tissue IHC). Record the cell type and compartment alongside intensity (general IHC practice).
Antibody validation	Three listed antibodies have Enhanced IHC status: HPA057100, CAB002053 and CAB040560 (HPA antibodies). This supports the reported IHC pattern, but a working assay still needs section level controls (general IHC practice).
Compartment and stress state	CRYAB is cytoplasmic and can move to nuclear splicing speckles during heat shock (UniProt P02511). Assess a nuclear result against the sample context and controls; do not assume every nuclear deposit is specific (general IHC practice).
Topology and processing	CRYAB has no transmembrane segment or signal peptide, and its annotated chain spans residues 1–175 (UniProt P02511). UniProt also reports secretion, so extracellular signal needs context rather than automatic acceptance as cellular staining (UniProt P02511; general IHC practice).
IF/ICC Q: What pattern should a separate IF/ICC assessment compare against?	A: HPA reports enhanced plasma membrane and cytosol localization in ICC-IF images from A-431, U-251MG and U2OS (HPA subcellular ICC-IF). That observation belongs to IF/ICC interpretation; HPA tissue IHC describes a cytoplasmic profile in paraffin sections (HPA tissue IHC).

Why is my staining missing, weak or wrong?
Situation	Likely cause	Next action
No staining in cardiomyocytes or lens fiber cells.	These cell populations are reported High, so absent signal raises an assay or section quality question before it establishes absent CRYAB (HPA tissue IHC; general IHC practice).	Check a known positive section, reagent controls, antigen retrieval execution and detection steps; optimize locally without assuming a CRYAB specific retrieval requirement (general IHC practice).
Signal is weak or patchy across an otherwise expected positive population.	Target-specific fixation effects are not established by the supplied assay evidence. Verify with a matched IHC source before attributing a result to fixation.	Compare section integrity and staining uniformity with a positive control, then review retrieval and detection records for that run (general IHC practice).
Brown haze covers many cell types and obscures cytoplasm.	Excess nonspecific staining or detection background can hide the cytoplasmic pattern (general IHC practice; HPA tissue IHC: cytoplasmic profile).	Inspect a no primary control, review blocking and washing, and adjust antibody or detection conditions according to the assay’s validation (general IHC practice).
Unexpected strong staining appears in a listed Not detected cell type.	For example, adrenal gland glandular cells are Not detected in the supplied profile (HPA tissue IHC). Nonspecific binding, antibody cross-reactivity or endogenous enzyme activity are possible (general IHC practice).	Confirm the cell identity; compare a no primary control and an expected positive tissue section, then review blocking and endogenous enzyme quenching where applicable (general IHC practice).
The apparent positive signal is mainly nuclear.	Heat shock can move CRYAB to the nucleus (UniProt P02511), but the reported tissue IHC profile is cytoplasmic (HPA tissue IHC). Counterstain overlap or nonspecific deposit may also mislead compartment calls (general IHC practice).	Compare the chromogen with the nuclear counterstain, inspect cytoplasmic signal and controls, and report nuclear staining with its sample context (general IHC practice).
A membrane outline is read as the sole expected IHC pattern.	Enhanced plasma membrane localization is an ICC-IF observation (HPA subcellular ICC-IF); HPA describes the tissue IHC profile as cytoplasmic (HPA tissue IHC).	Check whether cytoplasmic staining is present in the expected cells and score the paraffin section using its IHC controls; reserve the membrane observation for IF/ICC comparison (HPA tissue IHC; HPA subcellular ICC-IF; general IHC practice).

Source: UniProt P02511 Human Protein Atlas tissue Human Protein Atlas subcellular

Experiment evidence

IHC & IF images showing CRYAB staining

IHC analysis of Alpha B Crystallin/CRYAB using anti-Alpha B Crystallin/CRYAB antibody (A03496-2). Alpha B Crystallin/CRYAB was detected in paraffin-embedded section of rat brain 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 2μg/ml rabbit anti-Alpha B Crystallin/CRYAB Antibody (A03496-2) 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.

A03496-2 · IHCIHC analysis of Alpha B Crystallin/CRYAB using anti-Alpha B Crystallin/CRYAB antibody (A03496-2). Alpha B Crystallin/CRYAB was detected in p

IF analysis of Alpha B Crystallin/CRYAB using anti-Alpha B Crystallin/CRYAB antibody (A03496-2). Alpha B Crystallin/CRYAB was detected in immunocytochemical section of U20S cells. Enzyme antigen retrieval was performed using IHC enzyme antigen retrieval reagent (AR0022) for 15 mins. The cells were blocked with 10% goat serum. And then incubated with 5μg/mL rabbit anti-Alpha B Crystallin/CRYAB Antibody (A03496-2) overnight at 4°C. DyLight®594 Conjugated Goat Anti-Rabbit IgG (BA1142) was used as secondary antibody at 1:100 dilution and incubated for 30 minutes at 37°C. The section was counterstained with DAPI. Visualize using a fluorescence microscope and filter sets appropriate for the label used.

A03496-2 · IFIF analysis of Alpha B Crystallin/CRYAB using anti-Alpha B Crystallin/CRYAB antibody (A03496-2). Alpha B Crystallin/CRYAB was detected in im

HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000109846-CRYAB/tissue/cerebral+cortex#imid_20694232

HPA · EyeHuman Protein Atlas IHC, Eye. Source: https://www.proteinatlas.org/ENSG00000109846-CRYAB/tissue/retina#imid_1338

HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000109846-CRYAB/tissue/colon#imid_20696446

HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000109846-CRYAB/tissue/liver#imid_20696463

HPA · ICC-IF A-431Human Protein Atlas immunofluorescence, A-431, antibody CAB002053; green = CRYAB, blue = nucleus, red = microtubules.

← swipe / scroll for more images →

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

Sample controls for CRYAB IHC & IF

🧪Run cerebellum first: Bergmann glia should stain strongly (HPA: High in Bergmann glia, cytoplasm/membrane). Use adrenal gland glandular cells as the negative tissue (HPA: Not detected); adjacent non-Bergmann cells on the cerebellar slide are candidate internal negatives and should show only background relative to the controls, without assuming every such cell lacks CRYAB.

Positive control tissue: Caudate (Glial cells, HPA High)

Negative control tissue: Adrenal gland (HPA Not detected)

ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show CRYAB in A-431, U-251MG, U2OS, with annotated localisation: Plasma membrane (enhanced), Cytosol (enhanced) (HPA subcellular).

Technical controls: Include a no-primary, secondary-only slide; a rabbit immunoglobulin control matched to the primary’s clonality and concentration; and CRYAB-knockout tissue as a biological negative (caption: rabbit primary; standard IHC controls). For the cerebellar slide, block endogenous peroxidase and check endogenous biotin background because the reported detection uses a biotin–streptavidin complex with DAB (caption: SABC/DAB).

⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected A03496-2 paraffin-section caption does not state the fixative (caption: fixative not stated). The reported IHC example uses heat retrieval in EDTA at pH 8.0; this establishes a workable condition, not that retrieval is required for every specimen (caption: heat-mediated EDTA retrieval). There is no matched evidence that frozen sections or IF are easier; in cerebellum, distinguish Bergmann-glial staining from DAB-like tissue pigment using the no-primary slide (HPA: High in Bergmann glia; standard IHC practice).

HPA tissue IHC evidence for CRYAB

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
Caudate	Glial cells	High	Protein (IHC)	HPA →
Cerebellum	Bergmann glia - cytoplasm/membrane	High	Protein (IHC)	HPA →
Cerebral cortex	Glial cells	High	Protein (IHC)	HPA →
Epididymis	Glandular cells	High	Protein (IHC)	HPA →
Eye	Lens fiber cells	High	Protein (IHC)	HPA →

Undetected expression · recommended negative controls

Tissue	Cell type	Level	Evidence	Source
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 →
Bronchus	Respiratory epithelial cells	Not detected	Protein (IHC)	HPA →

Section 3

Advanced CRYAB IHC Tips

Troubleshoot CRYAB staining in paraffin section chromogenic IHC using the catalog antibody’s tissue result and the reported expression patterns as reference points.

Which retrieval condition should I start with for CRYAB IHC?

Start with heat mediated retrieval in EDTA pH 8.0 for paraffin sections (datasheet A03496-2). That condition preceded CRYAB staining in rat brain with 2 μg/ml primary antibody overnight at 4°C, but the caption does not report the retrieval heating time (datasheet A03496-2). Keep section thickness, heating time and cooling consistent across a comparison set, then assess staining alongside tissue morphology (standard IHC practice). If staining is weak, vary heating time on serial sections before testing another retrieval buffer, and reject conditions that damage morphology or raise background (standard IHC practice).

How should I investigate weak staining when fixation history varies?

The selected paraffin section caption does not state a fixative, so CRYAB specific sensitivity to fixation is unknown (datasheet A03496-2). Record fixative, fixation duration and processing history for each specimen, and compare serial sections using the same EDTA pH 8.0 retrieval and detection workflow (standard IHC practice; datasheet A03496-2). Include a known positive section in each run so a weak specimen can be distinguished from a failed staining run (standard IHC practice). Interpret differences between fixation groups cautiously, because neither the reported tissue pattern nor CRYAB annotations establish a target specific fixation effect (HPA: tissue IHC; UniProt P02511).

Which cellular compartments should count as plausible CRYAB staining?

Prioritise cytoplasmic staining in the appropriate cell population: tissue IHC reports cytoplasmic expression, including high staining in glial cells and cardiomyocytes (HPA: tissue IHC). Cytosol and plasma membrane localisation are also reported by cell imaging, while CRYAB has no annotated transmembrane segment (HPA: subcellular; UniProt P02511 topology). Nuclear staining can be biologically plausible during heat shock, when CRYAB translocates to nuclear speckles, but that annotation alone does not establish the state of a particular section (UniProt P02511). Score cytoplasmic, membranous and nuclear patterns separately, and check unexpected patterns against morphology and staining controls before accepting them (standard IHC practice).

Could an isoform or modified epitope explain inconsistent staining?

The supplied CRYAB record lists 0 isoforms and a chain spanning residues 1–175, so an annotated isoform switch is not supported here (UniProt P02511). It places the small heat shock protein domain at residues 56–164 and reports phosphorylation at 19, 45 and 59 plus glycosylation sites at 41 and 170 (UniProt P02511). The antibody epitope is not supplied, so these annotations cannot establish whether a modification changes binding (datasheet A03496-2; UniProt P02511). If staining differs between preparations, compare serial sections under one retrieval condition and seek epitope mapping before assigning the difference to a modification (standard IHC practice).

How can I assess CRYAB by IF alongside a cell identity marker?

Treat IF as a separate assay: the selected antibody evidence describes chromogenic staining of paraffin sections and does not establish IF performance (datasheet A03496-2). Pair CRYAB with a marker for the expected cell population, such as a glial identity marker when examining brain, where glial staining is reported (HPA: tissue IHC; standard IF practice). Choose spectrally separated fluorophores and assign the CRYAB channel after checking unstained tissue for autofluorescence (standard IF practice). For a cytosolic epitope, assess permeabilisation after fixation; CRYAB has no transmembrane segment, and the antibody epitope’s accessibility is unspecified (UniProt P02511 topology; datasheet A03496-2; standard IF practice).

What should I check when DAB staining appears diffuse?

The selected tissue example used 10% goat serum, biotinylated goat anti rabbit secondary antibody, streptavidin biotin detection and DAB (datasheet A03496-2). Check a section without primary antibody to reveal detection reagent background, and apply an endogenous peroxidase block before DAB development as a general chromogenic IHC step (standard IHC practice). If background persists, examine whether the biotin based detection system contributes staining and compare with an appropriate alternative detection system (standard IHC practice). Keep washes and DAB development consistent, then judge diffuse colour against cell morphology and the expected cytoplasmic pattern (standard IHC practice; HPA: tissue IHC).

How should I quantify CRYAB across heterogeneous tissue sections? ⚠ ANSWER MARKED FOR VERIFICATION

Define the cell population and compartment before scoring, because reported CRYAB staining varies by tissue and cell type (HPA: tissue IHC). For chromogenic sections, record the percentage of positive target cells and an intensity based H score, or measure positive cell density per mm² of evaluable tissue (standard IHC practice). Normalise cell counts to the number of eligible cells and density to annotated tissue area, excluding folds, necrosis and section edges by a rule set before review (standard IHC practice). Use the same retrieval, detection and scoring thresholds across sections, and report cytoplasmic and nuclear scores separately if both are observed (standard IHC practice; UniProt P02511).

How do I distinguish plausible CRYAB positivity from staining artefact?

A plausible result follows cell identity and compartment: glial cells in brain and cardiomyocytes in heart show high reported staining, with tissue IHC chiefly describing cytoplasmic expression (HPA: tissue IHC). Isolated nuclear staining needs context because nuclear translocation is reported during heat shock, while routine tissue staining alone cannot establish that stress state (UniProt P02511). Suspect artefact when signal concentrates at section edges or necrotic areas, follows an implausible cell population, or appears in a no primary control (standard IHC practice). Check endogenous peroxidase background and compare the finding with a concurrently stained positive section before assigning biological meaning (standard IHC practice).

Boster reagents

Best CRYAB / Alpha-crystallin B chain IHC Antibodies

A03496-2 has IHC images from rat brain and human cancer paraffin sections, plus an IF image from U20S cells (A03496-2 image captions).

Real IHC data

Anti-Alpha B Crystallin/CRYAB Antibody ®

Cat # A03496-2

View product →

The rendered SKU, A03496-2, has IHC images from rat brain and human lung, gastric, and skin cancer paraffin sections (A03496-2 IHC captions). Its IF image shows U20S cells; the catalog also lists ICC and IF applications (A03496-2 IF caption; catalog applications).

Which to pick: Choose A03496-2 for paraffin-section IHC: its captions document EDTA pH 8 retrieval and chromogenic detection, but do not report the fixative (A03496-2 IHC captions). Choose A03496-2 for IF/ICC when an image is useful; its IF caption documents U20S cells, whereas M03496 has no supplied IF image and is listed as a rabbit monoclonal (A03496-2 IF caption; M03496 catalog). For work across the listed species, A03496-2 covers human, monkey, mouse, and rat, while M03496 lists human and rat (catalog reactivity).

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

References

UniProt Consortium. UniProt entry P02511 (CRYAB_HUMAN, Alpha-crystallin B chain).
Human Protein Atlas. CRYAB tissue IHC expression (reliability: Enhanced).
Human Protein Atlas. CRYAB subcellular location (ICC-IF): Localized to the plasma membrane and cytosol..
Human Protein Atlas. CRYAB antibody validation summary (3 antibodies).
Expression of CRYAB with the angiogenesis and poor prognosis for human gastric cancer. Medicine 2019 — PMC6855521.
High α B-crystallin and p53 co-expression is associated with poor prognosis in ovarian cancer. Bioscience reports 2019 — PMC6579977.
Crystallin Alpha-B Overexpression as a Possible Marker of Reactive Astrogliosis in Human Cerebral Contusions. Frontiers in cellular neuroscience 2022 — PMC8963874.
Cluster analyses of the TCGA and a TMA dataset using the coexpression of HSP27 and CRYAB improves alignment with clinical-pathological parameters of breast cancer and suggests different epichaperome influences for each sHSP. Cell stress & chaperones 2021 — PMC8943080.
PubMed PMID:838078 — UniProt-cited evidence.
PubMed PMID:2387586 — UniProt-cited evidence.
PubMed PMID:1407707 — UniProt-cited evidence.