Why pet “component” results show up in allergy conversations

Component‑resolved diagnostics (CRD) measures IgE to individual molecules within an allergen (for example, Can f 1, Can f 2, Can f 5 for dog; Fel d 1 for cat). These markers can clarify which proteins your immune system targets and sometimes refine counseling (e.g., male vs female dog exposure). CRD does not replace clinical history, and it does not change how allergy immunotherapy extracts are made in the U.S.; immunotherapy uses whole allergen extracts rather than single purified components.

• Wyndly’s at‑home blood test is extract‑based; it screens for the 40 most common environmental allergens (e.g., cat dander, dog dander, grasses, trees, dust mites). It does not include component IgE by default.

• If you already have component results (ImmunoCAP, ALEX/ISAC, etc.) from the last 5 years, upload them. Our physicians will review and incorporate them when tailoring your plan.

What the key pet components mean

Below are the component markers we see referenced most often and how we use them alongside your history and extract testing.

Dog components

• Can f 1 (lipocalin) and Can f 2 (lipocalin)

• Major dog salivary/dander proteins; sensitization to Can f 1/2 is common in dog‑allergic patients and is associated with respiratory symptoms.

• Can f 5 (prostatic kallikrein)

• Produced in the prostate of male dogs; detectable in male dog urine, dander, and hair.

• Cross‑reacts with human prostate‑specific antigen (PSA); rare patients with Can f 5 IgE can have semen‑related reactions.

• Monosensitization to Can f 5 (with negative Can f 1/2/3/4/6) has been linked to reactions primarily to male dogs; some data suggest tolerance to female dogs in such cases.

Cat components

• Fel d 1 (secretoglobin/uteroglobin)

• The dominant cat allergen (accounts for most cat‑dander IgE reactivity) produced largely in sebaceous and salivary glands; highly airborne and persistent in environments.

How Wyndly uses (and doesn’t use) component data

• Formulation: SLIT allergy drops and SCIT shots are prepared from standardized whole extracts (e.g., “cat dander,” “dog dander”). We do not compound with purified single components like Can f 5 or Fel d 1. Component results therefore do not change which extract is used, but they can sharpen counseling and exposure strategies.

• Counseling and expectations:

• Dog Can f 5‑only (mono‑sensitized): We discuss that symptoms may occur chiefly around intact male dogs; some patients tolerate female or castrated male dogs better. Immunotherapy still targets dog dander extract because Can f 5 is present in whole‑dog exposures.

• Dog lipocalins (Can f 1/2 ± others): Broader dog reactivity; symptoms likely around both male and female dogs.

• Cat Fel d 1‑positive: Consistent with true cat allergy; Fel d 1 dominates cat dander allergenicity and correlates with asthma risk/severity in some cohorts.

• Access and logistics: If you have a component panel within 5 years, we’ll review it to speed plan design and counseling. Otherwise, Wyndly’s extract‑based test plus your history is sufficient to start care.

Example: de‑identified lab excerpts (how to read them)

The following examples are illustrative; formats vary by lab.

• Example A — Dog components

• Dog dander extract sIgE: 6.2 kUA/L (Class 3)

• Can f 1: 3.5 kUA/L (Class 3)

• Can f 2: 0.9 kUA/L (Class 2)

• Can f 5: <0.10 kUA/L (negative)

• Interpretation: Broad lipocalin sensitization; expect symptoms with male and female dogs. Immunotherapy: dog dander extract.

• Example B — Dog Can f 5 monosensitization

• Dog dander extract sIgE: 1.2 kUA/L (Class 2)

• Can f 1/2/3/4/6: <0.10 (negative)

• Can f 5: 1.1 kUA/L (Class 2)

• Interpretation: Male‑dog predominant reactivity; counsel about female/neutered male tolerance possibilities; immunotherapy still uses dog dander extract because real‑world exposure includes Can f 5.

• Example C — Cat components

• Cat dander extract sIgE: 9.8 kUA/L (Class 4)

• Fel d 1: 8.1 kUA/L (Class 4)

• Interpretation: Major cat allergen sensitization; consistent with clinical cat allergy; immunotherapy: cat dander extract.

Practical guidance for patients and assistants

• When to request component testing:

• You’re deciding between adopting a male vs female dog and already have dog allergy—Can f 5 can be informative.

• You have discordant results (e.g., dog extract borderline but strong symptoms); components can clarify primary vs cross‑reactive sensitization patterns.

• When extract testing alone is enough:

• Most treatment decisions (starting SLIT, setting targets, and step‑up plans) rely on history plus extract‑specific IgE. That’s why Wyndly’s default test is extract‑based.

• How to share existing results with Wyndly:

• Upload a PDF or clear portal screenshot of the component panel dated within the last 5 years to your Wyndly portal or bring it to your consult. Our physicians will document it and adjust counseling accordingly.

Component meanings at a glance

How this affects Wyndly therapy

• SLIT with Wyndly is doctor‑designed, evidence‑based, and uses whole extracts (e.g., dog dander, cat dander). Component positivity does not change which extract is included, but it can:

• Inform pet‑selection counseling (e.g., Can f 5 monosensitization).

• Help set expectations for response and exposure control.

• Ready to start? If you have prior testing ≤5 years old, we can usually begin quickly after a physician review. Otherwise, start with our extract‑based at‑home test and telehealth consult.

Frequently asked questions

Does Wyndly run component testing? By default, no. Our CLIA‑certified panel is extract‑based to identify your triggers and start treatment. If you already have components (e.g., Can f 5, Fel d 1), upload them (≤5 years old) and we’ll use them for counseling.

If I’m only positive to Can f 5, can I live with a female dog? Possibly. Can f 5 is male‑dog prostatic kallikrein; mono‑sensitized patients may tolerate female/neutered male dogs better. Individual responses vary, so we combine test results with your history and trial exposures.

Does neutering a male dog reduce Can f 5 exposure? Can f 5 is prostate‑derived; castration lowers prostatic secretions and may reduce Can f 5 shedding. However, published guidance focuses on male vs female exposure rather than a guaranteed “fix.” Practical counseling remains individualized.

If Fel d 1 is my only cat component, do I still need immunotherapy? If you’re symptomatic and extract testing confirms cat allergy, immunotherapy can help regardless of component pattern because extracts contain the relevant cat proteins (including Fel d 1).

Will component patterns change my SLIT formulation? No. Current SLIT and SCIT in the U.S. use whole extracts. Components guide counseling; formulation remains extract‑based.

Do components predict asthma risk? Some studies associate Fel d 1 (cat) and certain dog lipocalins with asthma risk or more severe rhinitis, but care decisions still hinge on your symptoms and goals.

What if my extract is positive but components are negative (or vice‑versa)? We treat the patient, not the number. Discordance can reflect cross‑reactivity, test thresholds, or laboratory differences; your physician will integrate results with history and, if needed, repeat testing.

Structured data (FAQPage)

Sources

• Thermo Fisher Allergen Encyclopedia

• Peer‑reviewed literature

• AAAAI & education resources

• Wyndly care pages