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ACKR2 / Atypical chemokine receptor 2 · IHC design guide
Design Immunohistochemistry for ACKR2
This IHC guide identifies cytoplasmic ACKR2 staining in placenta and ciliated cells (HPA tissue IHC). It pairs that pattern with the catalog antibody’s paraffin-section workflow and 0.5–1 μg/mL working range (datasheet A05491-2).
Evidence assembled Oct 2026 · For research use; verify linked source records and product datasheet before use
ACKR2 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 placenta and ciliated cells (HPA tissue IHC) | |
| Staining pattern | Cytoplasmic signal in syncytiotrophoblasts and ciliated cells (HPA tissue IHC) | |
| Antigen retrieval | Citrate pH 6 HIER, heat-mediated (datasheet A05491-2) | |
| Positive control | Bronchus+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 formalin fixation consistent across sections. (standard IHC practice; not target-specific) | |
| Caveat | Ligand stimulation can shift ACKR2 toward the cell surface (UniProt) | |
| Regulation | Ligand stimulation raises surface ACKR2 (UniProt) | |
| Isoform / epitope | No isoforms annotated; extracellular and cytoplasmic regions differ (UniProt) |
Section 1
Recommended ACKR2 IHC & IF Protocols
The catalog antibody’s IHC-P protocol (datasheet A05491-2) accompanies published methods for human kidney (PMC4699014) and lung cancer tissue arrays and animal sections (PMC10086750).
| Sample | Paraffin-embedded human placenta tissue; fixative not specified (datasheet A05491-2) |
| Fixation | Image fixative and duration unreported (datasheet A05491-2); verify before use. |
| Sectioning | 4–5 µm sections on charged slides (standard) |
| Deparaffinisation | Xylene, graded ethanol series to water (standard) |
| Antigen retrieval | Heat retrieval: Citrate pH 6, 20 min (datasheet A05491-2) |
| Peroxidase block | 3% H2O2, 10 min, room temperature (standard) |
| Blocking | 10% goat serum (datasheet A05491-2) |
| Primary antibody | Rabbit anti-ACKR2, 0.5-1μg/ml (datasheet A05491-2) |
| Primary incubation | Overnight at 4 °C (datasheet A05491-2) |
| Detection | Streptavidin-biotin complex (SABC), DAB chromogen (datasheet A05491-2) |
| Counterstain | Hematoxylin, blue, dehydrate and mount (standard) |
| Expected result | ACKR2-positive staining in ciliated cells (tip of cilia) of bronchus (HPA tissue IHC: High). HPA tissue profile: Cytoplasmic expression mainly in placenta and ciliated cells. No signal in the no-primary control. |
💡Decision noteStart with heat-mediated citrate retrieval at pH 6 for the catalog antibody (datasheet A05491-2); neither published excerpt specifies retrieval (PMC4699014; PMC10086750).
Section 2
What Is the Expected ACKR2 Staining Pattern?
ACKR2 is a seven-pass membrane receptor found mainly in endocytic vesicles and recycling endosomes, with some cell-surface localization (UniProt O00590 topology and subcellular location). In tissue IHC, expect cell-associated cytoplasmic staining chiefly in placental syncytiotrophoblasts, plus staining in selected ciliated epithelia (HPA tissue IHC). HPA rates its tissue pattern Enhanced, while describing only medium consistency with RNA expression (HPA tissue IHC).
| Strong syncytiotrophoblast staining in placenta, or strong signal at bronchial ciliary tips and fallopian-tube cilia. | These are reported high-staining cell populations (HPA tissue IHC). Cytoplasmic or vesicular signal also fits the receptor's endosomal distribution (UniProt O00590 subcellular location). Score the named cells and structures; staining throughout neighboring cells is a different observation. |
| Predominantly nuclear staining in a paraffin section, without the expected cytoplasmic or ciliary pattern. | Treat this as discordant for tissue IHC, pending controls (HPA tissue IHC; UniProt O00590 subcellular location). HPA lists nucleoplasm only as an additional ICC-IF location, which does not establish a predominantly nuclear IHC pattern (HPA subcellular ICC-IF). |
| Strong signal in unrelated cells while expected positive cells on the same section remain unstained. | Suspect off-target binding or endogenous detection activity and check the controls (standard IHC practice). HPA's levels are cell-specific: appendix endocrine cells are not detected, although UniProt reports ACKR2 in appendix lymphatics (HPA tissue IHC; UniProt O00590 tissue specificity). |
| A uniform haze covers positive cells, negative cells, and extracellular areas. | This distribution is background rather than interpretable ACKR2 localization (standard IHC practice; UniProt O00590 subcellular location). Reassess nonspecific binding, detection background, and washing with appropriate control sections before scoring weak signal (standard IHC practice). |
| No signal appears in placental syncytiotrophoblasts on an otherwise evaluable section. | Placental syncytiotrophoblasts are a high-staining HPA reference, so this result warrants an assay check (HPA tissue IHC). A negative test section alone cannot distinguish low ACKR2 expression from failed retrieval, antibody detection, or tissue processing (standard IHC practice). |
💡Expected ACKR2 appearanceCall positive a cell-associated cytoplasmic or vesicular signal in placental syncytiotrophoblasts, or strong localized ciliary staining in HPA-listed epithelia; regard uniform haze or dominant nuclear stain as suspect (HPA tissue IHC; UniProt O00590 subcellular location; standard IHC practice).
| Compartment and trafficking (UniProt O00590 subcellular location and topology). | ACKR2 spans the membrane seven times but predominantly resides in endocytic vesicles; ligand stimulation can change membrane versus vesicle distribution (UniProt O00590). Do not require a continuous cell-surface rim to call an otherwise cell-specific cytoplasmic pattern plausible. |
| Cell-specific reference patterns (HPA tissue IHC; UniProt O00590 tissue specificity). | HPA reports high signal in placenta syncytiotrophoblasts and two ciliated-cell sites, medium signal in duodenal enterocytes, and low signal in colon and rectum endothelial cells (HPA tissue IHC). UniProt also describes lymphatic endothelium; ordinary vascular endothelium is therefore a poor blanket positive criterion (UniProt O00590 tissue specificity; HPA tissue IHC). |
| Evidence strength and antibody choice (HPA tissue IHC; HPA antibodies). | HPA calls the tissue pattern Enhanced but notes medium staining-to-RNA consistency (HPA tissue IHC). Its HPA013819 entry has Enhanced IHC validation; HPA073493 has Supported ICC validation without an IHC rating (HPA antibodies). Keep those application ratings distinct when interpreting a paraffin result. |
| Detection background (standard IHC practice). | Endogenous enzyme activity and nonspecific binding can create chromogenic signal unrelated to the target (standard IHC practice). Appropriate detection-only and tissue controls help distinguish this from cell-restricted ACKR2 staining; HPA's tissue levels do not diagnose the source of background (HPA tissue IHC; standard IHC practice). |
| IF/ICC Q: Should its distribution match paraffin IHC (HPA subcellular ICC-IF)? | A: HPA supports vesicles and cytosol in ICC-IF and additionally approves nucleoplasm (HPA subcellular ICC-IF). Those observations provide compartment context, but ICC-IF is a separate application; its additional nuclear location does not validate nuclear-dominant tissue IHC (HPA subcellular ICC-IF; HPA tissue IHC). |
| Situation | Likely cause | Next action |
|---|---|---|
| Placental syncytiotrophoblasts show no stain (HPA tissue IHC). | The expected high-signal reference failed; the cause remains undetermined from that result alone (HPA tissue IHC; standard IHC practice). | Check section quality, retrieval, antibody dilution, detection reagents, and a positive-control section; change one workflow variable at a time (standard IHC practice). |
| The whole section develops diffuse brown haze (standard IHC practice). | Nonspecific antibody binding or detection background may obscure cell-specific signal (standard IHC practice). | Review detection-only controls, blocking, washing, and development time; score only a resolved cellular pattern (standard IHC practice). |
| Nuclei stain more strongly than cytoplasm in paraffin IHC (HPA tissue IHC). | This differs from HPA's cytoplasmic tissue profile; HPA's additional nuclear observation comes from ICC-IF (HPA tissue IHC; HPA subcellular ICC-IF). | Compare positive tissue and detection controls, then reassess localization with an independently validated IHC antibody if needed (standard IHC practice; HPA antibodies). |
| Strong stain appears in an HPA-negative cell population (HPA tissue IHC). | Off-target binding or endogenous detection activity is possible; a tissue name alone may hide differences between cell populations (HPA tissue IHC; standard IHC practice). | Identify the stained cells, inspect detection controls, and compare the same cell type with HPA's entries before calling it ACKR2 (HPA tissue IHC; standard IHC practice). |
| Ciliary staining is absent, but other epithelial areas stain (HPA tissue IHC). | The result misses the high ciliary patterns reported for bronchus and fallopian tube (HPA tissue IHC). | Confirm that intact cilia and the specified cell type are present, then compare a known-positive section and background controls (HPA tissue IHC; standard IHC practice). |
| A weak endothelial signal is difficult to score (HPA tissue IHC). | HPA reports low signal in colon and rectum endothelium and no detection in cerebral-cortex endothelium; endothelial staining is context-dependent (HPA tissue IHC). | Record vessel type and tissue, compare a stronger positive reference, and avoid classifying every vessel by one endothelial result (HPA tissue IHC; standard IHC practice). |
Experiment evidence
IHC & IF images showing ACKR2 staining
A05491-2 · IHCIHC analysis of ACKR2 using anti-ACKR2 antibody (A05491-2). ACKR2 was detected in paraffin-embedded section of human placenta tissue. Heat m
A30785 · IHCImmunohistochemical analysis of paraffin-embedded human Colon cancer. 1, Antibody was diluted at 1:200(4° overnight). 2, Tris-EDTA,pH9.0 was
A30785 · IFImmunofluorescence analysis of COS7 cells, using CCBP2 Antibody. The picture on the right is blocked with the synthesized peptide.
HPA · Cerebral cortexHuman Protein Atlas IHC, Cerebral cortex. Source: https://www.proteinatlas.org/ENSG00000144648-ACKR2/tissue/cerebral+cortex#imid_3418116
HPA · ColonHuman Protein Atlas IHC, Colon. Source: https://www.proteinatlas.org/ENSG00000144648-ACKR2/tissue/colon#imid_3418042
HPA · LiverHuman Protein Atlas IHC, Liver. Source: https://www.proteinatlas.org/ENSG00000144648-ACKR2/tissue/liver#imid_3418051
HPA · KidneyHuman Protein Atlas IHC, Kidney. Source: https://www.proteinatlas.org/ENSG00000144648-ACKR2/tissue/kidney#imid_3418052
HPA · ICC-IF RT-4Human Protein Atlas immunofluorescence, RT-4, antibody HPA073493; green = ACKR2, blue = nucleus, red = microtubules.
HPA · ICC-IF RT-4Human Protein Atlas immunofluorescence, RT-4, antibody HPA073493; green = ACKR2, blue = nucleus, red = microtubules.
← swipe / scroll for more images →
Real IHC / IF data behind the staining-pattern expectations in this section.
Sample controls for ACKR2 IHC & IF
🧪Run placenta first: syncytiotrophoblasts should stain (HPA: High in syncytiotrophoblasts). Use adrenal gland as a negative tissue, focusing on glandular cells (HPA: Not detected in adrenal gland glandular cells); on the placenta slide, adjacent cells outside the stained syncytiotrophoblast compartment should provide an internal background reference.
Positive control tissue: Bronchus (Ciliated cells (tip of cilia), HPA High)
Negative control tissue: Adrenal gland (HPA Not detected)
ICC-IF cell lines (HPA subcellular resource): HPA ICC-IF images show ACKR2 in RT-4, U2OS, with annotated localisation: Vesicles (supported), Cytosol (supported) (HPA subcellular).
Technical controls: Include a no-primary (secondary-only) control, a matched rabbit IgG control of the same isotype and clonality class as the catalog primary (caption: rabbit anti-ACKR2), and ACKR2 knockout material as a biological specificity control if available. For the placenta IHC run, block endogenous peroxidase and biotin before the biotin–streptavidin/DAB detection used in the example (caption: SABC with DAB).
⚠️Feasibility: No target-specific fixation window or fixation effect is reported, and the fixative in the A05491-2 placenta paraffin-section caption is unreported (caption: fixative not stated). The example uses heat retrieval in citrate buffer at pH 6 for 20 minutes, so that retrieval condition is a practical starting point rather than evidence that retrieval is required (caption: citrate retrieval). The supplied evidence does not establish whether frozen sections or IF/ICC are easier; for the placenta example, endogenous peroxidase or biotin can create background with biotin–streptavidin/DAB detection (caption: SABC with DAB; standard IHC practice).
HPA tissue IHC evidence for ACKR2
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 |
|---|---|---|---|---|
| Bronchus | Ciliated cells (tip of cilia) | High | Protein (IHC) | HPA → |
| Fallopian tube | Ciliated cells (cilia axoneme) | High | Protein (IHC) | HPA → |
| Placenta | Syncytiotrophoblasts | High | Protein (IHC) | HPA → |
| Duodenum | Enterocytes | Medium | Protein (IHC) | HPA → |
| Nasopharynx | Ciliated cells (cell body) | Medium | Protein (IHC) | HPA → |
Undetected expression · recommended negative controls
| Tissue | Cell type | Level | Evidence | Source |
|---|---|---|---|---|
| Adrenal gland | Glandular cells | Not detected | Protein (IHC) | HPA → |
| Appendix | Endocrine cells | Not detected | Protein (IHC) | HPA → |
| Caudate | Glial cells | Not detected | Protein (IHC) | HPA → |
| Cerebellum | Cells in granular layer | Not detected | Protein (IHC) | HPA → |
| Cerebral cortex | Endothelial cells | Not detected | Protein (IHC) | HPA → |
Section 3
Advanced ACKR2 IHC Tips
Troubleshoot ACKR2 staining in paraffin sections by checking retrieval, cell identity, subcellular pattern, and controls before assigning biological meaning.
What retrieval should I try first when ACKR2 staining is weak?
Use heat-mediated antigen retrieval in citrate buffer at pH 6 for 20 minutes (datasheet A05491-2). This is the condition documented for ACKR2 detection in paraffin-embedded human placenta, followed by 1 μg/ml primary antibody overnight at 4°C (datasheet A05491-2). If staining remains weak, vary heating time in matched sections while holding antibody concentration and detection constant, then inspect tissue morphology (standard IHC practice). Include a placenta control in each run because syncytiotrophoblast staining is reported as high (HPA: placenta syncytiotrophoblasts, High). Excessive retrieval can damage morphology or raise background, so select the mildest condition that gives a reproducible, anatomically plausible pattern (standard IHC practice).
Could fixation explain weak or uneven ACKR2 staining?
ACKR2-specific fixation sensitivity is unknown: the selected paraffin-section caption does not state its fixative (datasheet A05491-2). Record fixative, time to fixation, and fixation duration for each specimen, because these variables affect antigen preservation and section quality in chromogenic IHC (standard IHC practice). If fixation is suspected, compare matched samples fixed for 6 and 24 hours in neutral buffered formalin as a local pilot, rather than treating either interval as validated for ACKR2 (standard IHC practice). Process and retrieve the comparison sections together in citrate pH 6 for 20 minutes, then compare specific staining and background (datasheet A05491-2; standard IHC practice).
Should ACKR2 appear on the membrane or inside cells?
Expect a substantial intracellular component: ACKR2 predominantly occupies endocytic vesicles and also cycles through the cell membrane (UniProt O00590 subcellular location). Ligand stimulation promotes internalisation and receptor recycling, so membrane-only scoring can miss biologically plausible staining (UniProt O00590; PubMed:18201974). In paraffin-section IHC, assess punctate or cytoplasmic signal alongside any membrane accentuation, using cell morphology and a matched negative control to judge specificity (UniProt O00590 subcellular location; standard IHC practice). HPA reports mainly cytoplasmic tissue expression in placenta and ciliated cells, while its cell imaging supports vesicles and cytosol (HPA: tissue profile; HPA: subcellular location). Do not interpret staining pattern alone as a measure of ligand uptake (UniProt O00590 function).
How should epitope location affect my ACKR2 IHC controls?
ACKR2 has 7 transmembrane segments and no annotated isoforms in the supplied record, so first obtain the antibody's immunogen or epitope information before assigning a stained compartment to a particular molecular form (UniProt O00590 topology and isoforms). Residues 1–50 are extracellular, whereas residues 315–384 form a cytoplasmic tail; accessibility can therefore depend on the mapped epitope (UniProt O00590 topology; standard IHC practice). The record places a glycosylation site at residue 19 and phosphorylation sites including 339 and 343, but supplies no evidence that these modifications alter this antibody's IHC staining (UniProt O00590 modifications; datasheet A05491-2). Compare retrieval conditions and controls empirically rather than attributing a weak result to a modification (standard IHC practice).
How can I check an ACKR2 IHC pattern with multiplex IF?
Treat multiplex IF as a separate validation experiment, since the selected antibody evidence here documents chromogenic staining of paraffin sections, not an IF procedure (datasheet A05491-2). Pair ACKR2 with a validated marker of the expected cell population, such as a syncytiotrophoblast marker in placenta, and compare the overlap with the IHC distribution (HPA: placenta syncytiotrophoblasts, High; standard IF practice). Choose a spectrally distinct, preferably far-red fluorophore after checking tissue autofluorescence and single-stain controls (standard IF practice). If the epitope maps to extracellular residues 1–50, test staining without permeabilisation; if it maps to the cytoplasmic tail at 315–384, test controlled permeabilisation (UniProt O00590 topology; standard IF practice).
What should I check when DAB covers most of the section?
First compare the stained section with a no-primary control and inspect whether diffuse colour follows tissue edges, damaged areas, or the detection system rather than plausible ACKR2-bearing cells (standard IHC practice). The documented placenta procedure used 10% goat serum, 1 μg/ml rabbit primary overnight at 4°C, and a biotinylated secondary before streptavidin–biotin detection with DAB (datasheet A05491-2). In that workflow, check endogenous peroxidase and biotin background, secondary binding, and DAB development time with appropriate controls (standard IHC practice). Titrate primary concentration and shorten development one variable at a time while retaining citrate pH 6 retrieval initially (datasheet A05491-2; standard IHC practice).
How should I score ACKR2 staining across placenta sections? ⚠ ANSWER MARKED FOR VERIFICATION
Define the compartment and cell population before scoring; placental syncytiotrophoblasts are a reported high-staining population, and ACKR2 can appear intracellularly (HPA: placenta syncytiotrophoblasts, High; UniProt O00590 subcellular location). For chromogenic IHC, report the percentage of positive target cells and an intensity-weighted H-score from 0–300, with thresholds set from controls before reviewing groups (standard IHC practice). Normalise positive-cell counts to the number of evaluable target cells, or positive area to the measured viable target-region area in mm² (standard IHC practice). Keep retrieval, DAB development, imaging, and region selection consistent, and analyse membrane and cytoplasmic staining separately if both are present (standard IHC practice).
When is an apparent ACKR2-positive area likely to be artefact?
Give greatest weight to reproducible staining in anatomically plausible cells: syncytiotrophoblasts stain highly in HPA tissue IHC, and lymphatic endothelium is an ACKR2-associated site in the record (HPA: placenta syncytiotrophoblasts, High; UniProt O00590 tissue specificity). Vesicular or cytoplasmic staining can be plausible, while an isolated nuclear-only pattern needs independent confirmation because the receptor is predominantly endosomal and membrane-associated (UniProt O00590 subcellular location). Edge-restricted colour, necrotic regions, and signal in the no-primary control point toward processing or detection artefact (standard IHC practice). Check endogenous peroxidase and biotin controls when using DAB with streptavidin–biotin detection, then confirm any disputed cell assignment with morphology or a cell-type marker (datasheet A05491-2; standard IHC practice).
Boster reagents
Best ACKR2 / Atypical chemokine receptor 2 IHC Antibodies
Two anti-ACKR2 antibodies have paraffin-section IHC images from human placenta and colon cancer; one also has a COS7-cell IF image (catalog image captions).
Real IHC data
Anti-D6/ACKR2 Antibody ®
Cat # A05491-2
Real IHC data
Anti-CCBP2 ACKR2 Antibody
Cat # A30785
A05491-2 shows IHC on paraffin-embedded human placenta and lists Human reactivity (A05491-2 image caption; catalog applications/reactivity). A30785 shows IHC on paraffin-embedded human colon cancer and IF in COS7 cells; it lists Human, Mouse and Rat reactivity (A30785 image captions; catalog applications/reactivity).
Which to pick: For human tissue IHC, choose A05491-2 for the illustrated placenta workflow or A30785 for the illustrated colon cancer workflow (respective IHC image captions). For IF/ICC or planned Mouse or Rat work, choose polyclonal A30785 because those applications and species are listed for it (A30785 catalog dilution/application/reactivity data). The fixative is unreported in both IHC captions (A05491-2 and A30785 IHC image captions).
Each figure is that product's own IHC / IF validation image from its datasheet.
References
- UniProt Consortium. UniProt entry O00590 (ACKR2_HUMAN, Atypical chemokine receptor 2).
- Human Protein Atlas. ACKR2 tissue IHC expression (reliability: Enhanced).
- Human Protein Atlas. ACKR2 subcellular location (ICC-IF): Mainly localized to vesicles and cytosol. In addition localized to the nucleoplasm..
- Human Protein Atlas. ACKR2 antibody validation summary (2 antibodies).
- Integrated bioinformatics analysis reveals that CCBP2 and GPR87 are new GPCR-associated biomarkers for preeclampsia. Reproductive biology and endocrinology : RB&E 2024 — PMC11590348.
- Renal Protection by Genetic Deletion of the Atypical Chemokine Receptor ACKR2 in Diabetic OVE Mice. Journal of diabetes research 2016 — PMC4699014.
- Elevated ACKR2 expression is a common feature of inflammatory arthropathies. Rheumatology (Oxford, England) 2017 — PMC5850605.
- CXCL14 promotes metastasis of non-small cell lung cancer through ACKR2-depended signaling pathway. International journal of biological sciences 2023 — PMC10086750.
- PubMed PMID:9364936 — UniProt-cited evidence.
- PubMed PMID:9405404 — UniProt-cited evidence.
- PubMed PMID:14702039 — UniProt-cited evidence.
Immunohistochemistry protocol sheet for ACKR2 (Atypical chemokine receptor 2). Expected localisation Cytoplasmic staining in placenta and ciliated cells (HPA tissue IHC). Antigen retrieval: Citrate pH 6 HIER, heat-mediated (datasheet A05491-2). Validated IHC antibody: A05491-2 at 0.5-1μg/ml (the product's own IHC validation image is shown). Controls (HPA): positive Bronchus (Ciliated cells (tip of cilia)); negative Adrenal gland. IHC-P workflow on paraffin sections; fixative unspecified. Protocol steps: 1. Sample: Paraffin-embedded human placenta tissue; fixative not specified (datasheet A05491-2); 2. Fixation: Image fixative and duration unreported (datasheet A05491-2); 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: Citrate pH 6 , 20 min (datasheet A05491-2); 6. Peroxidase block: 3% H2O2, 10 min , room temperature (standard); 7. Blocking: 10% goat serum (datasheet A05491-2); 8. Primary antibody: Rabbit anti-ACKR2, 0.5-1μg/ml (datasheet A05491-2); 9. Primary incubation: Overnight at 4 °C (datasheet A05491-2). Watch for: Fixation: Keep formalin fixation consistent across sections. (standard IHC practice; not target-specific); Caveat: Ligand stimulation can shift ACKR2 toward the cell surface (UniProt); Isoform / epitope: No isoforms annotated; extracellular and cytoplasmic regions differ (UniProt); Regulation: Ligand stimulation raises surface ACKR2 (UniProt). Evidence: UniProt O00590, HPA tissue IHC · Enhanced, HPA ICC-IF · Mainly localized to vesicles and cytosol. In addition localized to…, Datasheet A05491-2, PMC4699014, PMC10086750. QR code links to https://www.bosterbio.com/bosterbio-gene-info-cards/ACKR2/immunohistochemistry-ihc-guide.