Identifying Bee & Wasp Venom Allergens
Sting history and specific IgE testing confirm the culprit insect venom.
- Api m 1: Major bee allergen (phospholipase A2)
- Ves v 5: Major wasp allergen (antigen 5 protein)
- ~5%: Sting reaction prevalence (systemic reactions, adults)
- 2: Diagnostic tests used (skin test + specific IgE)
Skin & serum testing
Skin prick and intradermal tests plus serum IgE pinpoint the venom.
Component-resolved diagnosis
Molecular allergen panels distinguish true sensitization from cross-reactivity.
Build-Up Phase — Stepwise Dose Escalation
Injections climb from micrograms to a maintenance dose over weeks.
- 0.01 µg: Starting dose (ultra-dilute venom)
- 100 µg: Target maintenance dose (standard protocol)
- ~16 wk: Conventional build-up (weekly increments)
- 1–3 days: Rush protocol (accelerated escalation)
Dose ladder schedule
Each visit doubles or steps up the venom dose under observation.
Rush vs conventional
Rush protocols compress escalation into days with closer monitoring.
IgG4 Blocking Antibodies Rise as IgE Falls
Venom-specific IgG4 climbs and competes with IgE for allergen binding.
- 10–100×: IgG4 fold-rise (over first year)
- transient: IgE early spike (weeks 1–8)
- IL-10 / TGF-β: Treg induction (tolerogenic cytokines)
- IgG4 ≫ IgE: Blocking ratio target (favorable ratio)
Blocking antibody mechanism
IgG4 intercepts venom allergen before it cross-links mast-cell IgE.
Regulatory T-cell shift
Tregs and IL-10 redirect the immune response toward tolerance.
Maintenance Phase — Sustaining Tolerance
A fixed dose every 4–8 weeks keeps blocking antibodies elevated.
- 4–8 wk: Maintenance interval (typical spacing)
- 3–5 yr: Recommended duration (full course)
- up to 12 wk: Interval extension (after stable years)
- >90%: Protection rate (against re-sting)
Long-term dosing schedule
Spacing widens gradually once tolerance is well established.
Monitoring during maintenance
Periodic sting challenges and IgG4 levels confirm ongoing protection.
Long-Term Sting Tolerance Outcome
Years after completing therapy most patients remain sting-tolerant.
- >80%: Protection after stopping (remain protected, 5–10 yr)
- few: Relapse risk factors (severe initial reaction)
- high: Field re-sting tolerance (vs untreated baseline)
- marked: Quality-of-life gain (reduced sting anxiety)
Durability of protection
Immune memory from years of therapy persists after discontinuation.
Residual risk management
Epinephrine auto-injectors remain advised for high-risk patients.