This website uses cookies to ensure you get the best experience on our website.
- Table of Contents
CXCR5 / C-X-C chemokine receptor type 5 · IHC design guide
Design Immunohistochemistry for CXCR5
Plan paraffin-section CXCR5 IHC with a 1:50 catalog antibody dilution (datasheet M00663-1). Interpret cytoplasmic immune-cell staining (HPA tissue IHC) alongside cell-membrane topology (UniProt), and check for presumed off-target binding (HPA tissue IHC).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
CXCR5 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 of some immune cells (HPA tissue IHC); cell membrane (UniProt) | |
| Staining pattern | A subset of immune cells shows cytoplasmic staining (HPA tissue IHC) | |
| Antigen retrieval | EDTA pH 8.0 HIER, heat-mediated (datasheet M00663-1) | |
| Positive control | Appendix+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 paraffin-section fixation consistent (standard IHC practice; not target-specific); Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image M00663-1) | |
| Caveat | Presumed off-target binding may mimic CXCR5 staining (HPA tissue IHC) | |
| Regulation | Mature B cells; regulation unreported (UniProt) | |
| Isoform / epitope | Two isoforms; epitope impact unknown; check loop vs tail (UniProt) |
Section 1
Recommended CXCR5 IHC & IF Protocols
The catalog antibody’s IHC-P protocol (datasheet: M00663-1) is paired with a published rheumatoid synovial tissue protocol (PMC1065316).
| Sample | Paraffin-embedded rat spleen tissue; fixative not specified (datasheet M00663-1) |
| Fixation | Image fixative and duration unreported (datasheet M00663-1); 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 M00663-1); 20 min, 95–100 °C (standard) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet M00663-1) |
| Primary antibody | Rabbit monoclonal (clone 20C58) anti-CXCR5, 1:50 (datasheet M00663-1) |
| Primary incubation | Overnight at 4 °C (datasheet M00663-1) |
| Detection | HRP-conjugated secondary, DAB chromogen (datasheet M00663-1) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | CXCR5-positive staining in non-germinal center cells of appendix (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression in a subset of immune cells. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated EDTA retrieval at pH 8.0 for the catalog antibody (datasheet: M00663-1). The published single-stain CXCR5 method does not specify retrieval (PMC1065316).
Section 2
What Is the Expected CXCR5 Staining Pattern?
CXCR5 is a seven-pass cell-membrane receptor expressed in mature B cells (UniProt P32302: topology and tissue specificity). In paraffin-section IHC, expect staining in subsets of immune cells, especially in lymphoid tissue; HPA describes the observed signal as cytoplasmic (HPA tissue IHC: profile). Interpret that signal with care: HPA rates tissue staining Enhanced but reports medium agreement with RNA data and presumed off-target binding (HPA tissue IHC: reliability).
| A subset of cells stains strongly in splenic white pulp or tonsil germinal centers, with discernible cell boundaries. | These are useful positive-pattern benchmarks: HPA reports high staining in white-pulp cells and tonsil germinal-center cells (HPA tissue IHC). Membrane-associated staining fits CXCR5 topology, while HPA also describes cytoplasmic IHC signal in some immune cells (UniProt P32302: topology; HPA tissue IHC: profile). |
| The strongest signal is nuclear, with little staining around cell boundaries. | A dominant nuclear pattern conflicts with the annotated membrane location and the reported cytoplasmic tissue-IHC profile (UniProt P32302: subcellular location; HPA tissue IHC: profile). Review the nuclear counterstain and detection controls before scoring it as CXCR5 (general IHC practice). |
| Many unrelated cells stain, including adipocytes in an adipose section or respiratory epithelium in a bronchus section. | HPA reports those cell types as undetected, so widespread signal there warrants investigation (HPA tissue IHC: negative tissues). Possible explanations include antibody cross-reactivity or endogenous chromogenic detection activity; use an appropriate negative-control slide to separate them (general IHC practice). |
| Color spreads across the section without distinct stained cells or tissue structures. | Diffuse deposit is hard to score as the subset-of-cells pattern reported by HPA (HPA tissue IHC: profile). Check reagent background, washes, blocking, and chromogen development against a detection-control slide (general IHC practice). |
| Expected positive compartments show no signal in a tonsil or spleen section. | Target-specific fixation effects are not established by the supplied assay evidence. Verify with a matched IHC source before attributing a result to fixation. |
💡Expected CXCR5 appearanceCall a result convincing when subset-restricted, strong staining appears in the HPA-reported lymphoid cell populations, with a membrane-associated or reported cytoplasmic pattern; dominant nuclear signal or widespread staining in HPA-undetected cell types warrants review (UniProt P32302: location; HPA tissue IHC: profile, positive and negative tissues).
| Membrane location and epitope orientation | CXCR5 has seven transmembrane segments and extracellular and cytoplasmic regions (UniProt P32302: topology). Epitope position would affect whether a staining pattern is plausible, but the supplied record gives no antibody epitope; interpret compartment claims accordingly. |
| Observed tissue-IHC pattern | HPA calls the tissue signal cytoplasmic in a subset of immune cells, despite UniProt's cell-membrane annotation (HPA tissue IHC: profile; UniProt P32302: subcellular location). Cytoplasmic color alone therefore does not prove an artefact or establish that every stained cell expresses CXCR5. |
| Choice of tissue and cell-level control | HPA reports high staining in appendix and lymph-node non-germinal-center cells, spleen white-pulp cells, and tonsil germinal-center cells (HPA tissue IHC: positive tissues). Score the named cell populations rather than treating each entire section as uniformly positive. |
| Specificity of an apparent positive | HPA labels tissue-IHC reliability Enhanced but notes medium agreement with RNA data and presumed off-target binding that was disregarded (HPA tissue IHC: reliability). HPA lists two antibodies with Enhanced IHC status; that status does not validate an unlisted catalog antibody (HPA antibodies: HPA042432, CAB026149). |
| Transcript and protein annotations | UniProt lists Long and Short isoforms and glycosylation sites at residues 28 and 196 (UniProt P32302: isoforms and glycosylation). The supplied evidence does not link either feature to a particular IHC intensity, retrieval condition, or antibody epitope. |
| IF/ICC Q: What pattern should an IF result show? | A: HPA summarizes CXCR5 as membrane-associated, consistent with UniProt, but supplies no ICC-IF image-bearing cell line and no ICC validation status for the listed antibodies (HPA subcellular; HPA antibodies; UniProt P32302: location). Assess IF on its own guide page; this IHC evidence does not establish an IF protocol. |
| Situation | Likely cause | Next action |
|---|---|---|
| Tonsil or spleen control is blank. | A missed reagent step, failed detection, or an unsuitable control section is possible (general IHC practice); HPA reports high staining only in specified cells within these tissues (HPA tissue IHC: positive tissues). | Confirm the expected compartment is present, then check antibody application, retrieval, detection reagents, and a known working positive control (general IHC practice). Do not infer a CXCR5-specific fixation effect from these data. |
| Every cell is similarly brown. | Uniform staining conflicts with HPA's subset-of-immune-cells description; excess detection background or endogenous activity may contribute (HPA tissue IHC: profile; general IHC practice). | Compare a no-primary control, check endogenous-activity blocking where relevant, and review washes and chromogen development (general IHC practice). |
| The section has hazy color but no scoreable cell outlines. | Nonspecific reagent deposition or insufficient washing can obscure cell-level localisation (general IHC practice). | Review blocking, reagent concentration, wash steps, and development time against a matched control section (general IHC practice). |
| Nuclear staining dominates. | The pattern is inconsistent with CXCR5's membrane annotation and HPA's cytoplasmic tissue-IHC profile (UniProt P32302: location; HPA tissue IHC: profile). | Inspect the counterstain separately and compare detection and no-primary controls before assigning CXCR5 positivity (general IHC practice). |
| A negative comparison tissue shows many positive cells. | HPA reports adipocytes in adipose tissue and respiratory epithelial cells in bronchus as undetected, although other cell populations in a section may differ (HPA tissue IHC: negative tissues). | Identify the stained cell type before scoring; compare no-primary and detection controls, then assess antibody specificity if staining persists (general IHC practice). |
| A lymphoid section shows a different stained-cell distribution than expected. | HPA reports different high-staining compartments across lymphoid tissues, and its reliability note records medium RNA agreement and disregarded presumed off-target binding (HPA tissue IHC: positive tissues and reliability). | Record tissue architecture and stained-cell identity, compare the matching HPA cell-level pattern, and seek independent specificity evidence before making a broad CXCR5 claim (HPA tissue IHC: positive tissues; general IHC practice). |
Experiment evidence
IHC & IF images showing CXCR5 staining
M00663-1 · IHCIHC analysis of CXCR5 using anti-CXCR5 antibody (M00663-1). CXCR5 was detected in a paraffin-embedded section of rat spleen tissue. Heat med
A00663 · IHCImmunohistochemical analysis of paraffin-embedded rat kidney tissue using anti-CXCR5 antibody. Counter stained with hematoxylin.
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000160683-CXCR5/tissue/cerebral+cortex#imid_15187106
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000160683-CXCR5/tissue/colon#imid_15187032
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000160683-CXCR5/tissue/liver#imid_15187033
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000160683-CXCR5/tissue/kidney#imid_15187042
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for CXCR5 IHC & IF
🧪Run spleen first: cells in its white pulp should stain (HPA: High in cells in white pulp). Use adipose tissue as the negative tissue, with adipocytes expected to show no CXCR5 staining (HPA: Not detected in adipocytes); on the spleen slide, assess background in cells without specific membrane labeling, without assuming a particular cell population is CXCR5-negative (UniProt P32302: cell membrane).
Positive control tissue: Appendix (Non-germinal center cells, 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 CXCR5; derive a cell-line control from the positive tissue's cell type (Non-germinal center cells) and confirm it by RNA or western blot first.
Technical controls: Include no-primary (secondary-only) and rabbit IgG isotype controls matched to the primary antibody’s clonality where applicable (caption: rabbit anti-CXCR5; standard IHC practice). A CXCR5 knockout specimen would provide a biological negative (standard IHC practice); block endogenous peroxidase when using HRP/DAB in spleen, and assess tissue autofluorescence if adapting the assay to IF (caption: rat spleen, HRP/DAB; standard IHC/IF practice).
⚠️Feasibility: A target-specific fixation window or fixation effect is unreported, and the selected-SKU paraffin-section caption does not state a fixative (caption: M00663-1). The illustrated spleen IHC procedure used heat retrieval in EDTA at pH 8.0; this shows a working retrieval condition, while dependence on retrieval is unreported (caption: M00663-1). The supplied evidence does not establish whether frozen sections or IF are easier; for spleen, check blood-rich areas for endogenous peroxidase background in chromogenic IHC (caption: rat spleen, HRP/DAB; standard IHC practice).
HPA tissue IHC evidence for CXCR5
Comprehensive Human Protein Atlas IHC scoring per tissue (reliability: Enhanced — Medium consistency between antibody staining and RNA expression data. Presumed off target binding observed and disregarded.). 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 | Non-germinal center cells | High | Protein (IHC) | HPA → |
| Duodenum | Endocrine cells | High | Protein (IHC) | HPA → |
| Lymph node | Non-germinal center cells | High | Protein (IHC) | HPA → |
| Spleen | Cells in white pulp | High | Protein (IHC) | HPA → |
| Tonsil | Germinal center 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 → |
| Breast | Adipocytes | Not detected | Protein (IHC) | HPA → |
| Bronchus | Respiratory epithelial cells | Not detected | Protein (IHC) | HPA → |
| Caudate | Glial cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced CXCR5 IHC Tips
Troubleshoot CXCR5 staining in paraffin sections by checking retrieval, cell identity, compartment, and controls before interpreting DAB signal (UniProt P32302; HPA tissue IHC).
What retrieval should I try first when CXCR5 staining is weak?
Start with heat-mediated EDTA retrieval at pH 8.0 for paraffin-section chromogenic IHC (datasheet M00663-1). The selected rat spleen image used that buffer before 1:50 primary antibody incubation overnight at 4°C, so it is the closest documented starting point (datasheet M00663-1). If staining remains weak, vary heating duration on adjacent sections while keeping antibody concentration, detection, and DAB development constant (standard IHC practice). Compare signal in splenic white pulp with background elsewhere on each section, and reject conditions that increase diffuse staining without improving cell-specific contrast (HPA: high in splenic white-pulp cells; standard IHC practice).
Could fixation explain absent or uneven CXCR5 staining?
CXCR5-specific fixation sensitivity is unknown: the selected paraffin-section caption does not state a fixative, and tissue staining patterns do not establish an optimal fixation condition (datasheet M00663-1; HPA tissue IHC). Record the fixative and duration for every specimen, and compare adjacent sections processed with the same pH 8.0 EDTA retrieval and detection conditions (datasheet M00663-1; standard IHC practice). When fixation histories differ, evaluate morphology and staining together before attributing a negative result to CXCR5 absence (standard IHC practice). Use a documented positive control in each run to distinguish a specimen-specific problem from a failed staining run (standard IHC practice).
Should CXCR5 DAB signal appear only at the cell surface?
CXCR5 is annotated as a cell-membrane receptor with 7 transmembrane segments, making membrane-associated staining an expected pattern (UniProt P32302 topology and subcellular location). HPA also reports cytoplasmic staining in a subset of immune cells, so cytoplasmic DAB alone is not decisive evidence of artefact (HPA tissue IHC). Assess whether signal follows identifiable cell boundaries or sits within intact cells, using a light hematoxylin counterstain to preserve those distinctions (standard IHC practice). Compare the pattern with nearby unstained cells and a no-primary control, and interpret diffuse extracellular pigment cautiously (standard IHC practice).
Can this stain distinguish CXCR5 isoforms or extracellular epitopes?
CXCR5 has Long and Short isoforms, but the supplied evidence does not map this antibody’s epitope or establish isoform-specific detection (UniProt P32302; datasheet M00663-1). Its annotated extracellular regions include residues 1–55 and 189–219, with glycosylation sites at 28 and 196 (UniProt P32302 topology and glycosylation). Those annotations help frame an epitope-accessibility question; they cannot identify which region this antibody recognizes (UniProt P32302; datasheet M00663-1). For unexpected staining, compare retrieval conditions and an independently validated antibody with a documented epitope, then report CXCR5 staining without assigning an isoform (standard IHC practice).
How can I investigate CXCR5 by multiplex IF alongside this IHC guide?
Treat multiplex IF as a separate validation exercise: the supplied image documents chromogenic staining in paraffin sections, with no IF result or reported fixative (datasheet M00663-1). Pair CXCR5 with a B-cell marker such as CD20 to check expected cell identity, while recognizing that other immune-cell patterns need their own validation (UniProt P32302: mature B-cell expression; standard IF practice). Choose spectrally separated fluorophores after inspecting unstained tissue for autofluorescence, and include single-color controls (standard IF practice). Adjust permeabilisation according to the documented antibody epitope: intracellular access may require it, whereas a surface-epitope comparison should preserve membrane staining (UniProt P32302 topology; standard IF practice).
How do I reduce widespread brown staining without losing CXCR5-positive cells?
First compare the stained section with a no-primary control and check whether pigment follows tissue edges, damaged areas, or expected cells (standard IHC practice). Include an endogenous-peroxidase block before HRP and DAB detection, since the selected image used a peroxidase-conjugated secondary and DAB (datasheet M00663-1; standard IHC practice). The documented tissue block was 10% goat serum; if background persists, review blocking, washes, primary concentration, and DAB development one variable at a time (datasheet M00663-1; standard IHC practice). Judge improvement by retaining discrete staining in appropriate immune-cell areas rather than by lowering all signal equally (HPA tissue IHC; standard IHC practice).
What is a defensible way to quantify CXCR5 IHC across sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define an anatomical region and cell population before scoring, then report the percentage of positive cells or positive-cell density per mm² (standard IHC practice). If intensity is reproducible, an H-score combines percentages at intensities 0–3 into a 0–300 score (standard IHC practice). Normalize counts to the number of eligible intact cells, or density to measured tissue area, while excluding folds, necrosis, and section edges by a prespecified rule (standard IHC practice). Score comparable regions across specimens because HPA reports staining in selected immune-cell compartments rather than uniform tissue-wide expression (HPA tissue IHC; standard IHC practice).
When should an apparent CXCR5-positive cell be considered artefactual?
A convincing result places signal in intact, identifiable cells and is compatible with a membrane receptor, while allowing for the cytoplasmic immune-cell pattern reported by HPA (UniProt P32302 subcellular location; HPA tissue IHC). Review a no-primary control and exclude staining confined to section edges, necrotic areas, or sites of endogenous peroxidase activity (standard IHC practice). Check cell identity against the region examined: HPA reports high staining in splenic white-pulp cells and tonsillar germinal-center cells, but its reliability note also flags presumed off-target binding (HPA tissue IHC). Resolve unexpected cell types or compartments with an independent antibody or orthogonal assay before calling them CXCR5-positive (standard IHC practice).
Boster reagents
Best CXCR5 / C-X-C chemokine receptor type 5 IHC Antibodies
Both anti-CXCR5 antibodies have IHC images from rat paraffin sections (M00663-1 and A00663 image captions). Both list human, mouse and rat reactivity; M00663-1 also lists IF/ICC (catalog applications and reactivity).
Real IHC data
Anti-CXCR5 Rabbit Monoclonal Antibody
Cat # M00663-1
Real IHC data
Anti-CXCR5 Antibody
Cat # A00663
M00663-1 lists IHC and IF/ICC, with an IHC image from rat spleen paraffin sections (catalog applications; M00663-1 image caption). A00663 lists IHC, with an IHC image from rat kidney paraffin sections (catalog applications; A00663 image caption).
Which to pick: For tissue IHC, M00663-1 offers a rabbit monoclonal antibody with a documented rat spleen paraffin-section workflow using EDTA retrieval and 1:50 primary dilution; the fixative is unreported (catalog clone; M00663-1 image caption). A00663 offers a rat kidney paraffin-section IHC example and a listed dilution of 1:50–1:200; its fixative is also unreported (A00663 image caption; catalog IHC dilution). For IF/ICC, choose M00663-1 because it lists those applications; for work across species, both list human, mouse and rat reactivity (catalog applications and reactivity).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry P32302 (CXCR5_HUMAN, C-X-C chemokine receptor type 5).
- Human Protein Atlas. CXCR5 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. CXCR5 subcellular location (ICC-IF): Membrane.
- Human Protein Atlas. CXCR5 antibody validation summary (2 antibodies).
- Chemokine receptors in the rheumatoid synovium: upregulation of CXCR5. Arthritis research & therapy 2005 — PMC1065316.
- The serum CXCL13 level is associated with the Glasgow Prognostic Score in extranodal NK/T-cell lymphoma patients. Journal of hematology & oncology 2015 — PMC4437674.
- Phenotype and function of CXCR5+CD45RA-CD4+ T cells were altered in HBV-related hepatocellular carcinoma and elevated serum CXCL13 predicted better prognosis. Oncotarget 2015 — PMC4792554.
- The chemokine receptor cxcr5 regulates the regenerative neurogenesis response in the adult zebrafish brain. Neural development 2012 — PMC3441421.
- PubMed PMID:1425907 — UniProt-cited evidence.
- PubMed PMID:7639692 — UniProt-cited evidence.
- PubMed PMID:9463416 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for CXCR5 (C-X-C chemokine receptor type 5). Expected localisation Cytoplasm of some immune cells (HPA tissue IHC); cell membrane (UniProt). Antigen retrieval: EDTA pH 8.0 HIER, heat-mediated (datasheet M00663-1). Validated IHC antibody: M00663-1 at 1:50 (the product's own IHC validation image is shown). Controls (HPA): positive Appendix (Non-germinal center cells); negative Adipose tissue. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded rat spleen tissue; fixative not specified (datasheet M00663-1); 2. Fixation: Image fixative and duration unreported (datasheet M00663-1); 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 M00663-1); 20 min, 95–100 °C (standard); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet M00663-1); 8. Primary antibody: Rabbit monoclonal (clone 20C58) anti-CXCR5, 1:50 (datasheet M00663-1); 9. Primary incubation: Overnight at 4 °C (datasheet M00663-1). Watch for: Fixation: Keep paraffin-section fixation consistent (standard IHC practice; not target-specific); Matched tissue-IHC evidence does not establish the fixation claim. Validate the specimen-specific method before use. (selected-SKU IHC image M00663-1); Caveat: Presumed off-target binding may mimic CXCR5 staining (HPA tissue IHC); Isoform / epitope: Two isoforms; epitope impact unknown; check loop vs tail (UniProt); Regulation: Mature B cells; regulation unreported (UniProt). Evidence: UniProt P32302, HPA tissue IHC · Enhanced, HPA ICC-IF · Membrane, Datasheet M00663-1, PMC1065316. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/CXCR5/immunohistochemistry-ihc-guide.