First Exposure: Allergen Uptake by Dendritic Cells
Placeholder: initial contact introduces peanut/nut protein to the immune system.
- trace: Allergen dose (Placeholder sub-note)
- rising: APC activation (Placeholder sub-note)
- none: Symptom onset (Placeholder sub-note)
- days: Time to prime (Placeholder sub-note)
Dendritic cell antigen capture
Placeholder: dendritic cells engulf allergen protein and migrate to lymph nodes.
Th2 Skewing and IgE Class Switching
Placeholder: presented antigen biases naive T cells toward a Th2 phenotype.
- IL-4/IL-13: Th2 cytokines (Placeholder sub-note)
- IgM→IgE: Class switch (Placeholder sub-note)
- increasing: B-cell activation (Placeholder sub-note)
- suppressed: Th1 balance (Placeholder sub-note)
Cytokine-driven class switching
Placeholder: IL-4 and IL-13 signal B cells to switch to IgE production.
Allergen-Specific IgE Antibody Production
Placeholder: plasma cells secrete IgE antibodies specific to the allergen.
- rising: IgE titer (Placeholder sub-note)
- allergen-specific: Specificity (Placeholder sub-note)
- active: Plasma cells (Placeholder sub-note)
- systemic: Circulation (Placeholder sub-note)
Plasma cell antibody secretion
Placeholder: secreted IgE circulates and binds receptors on mast cells and basophils.
Sensitization Without Clinical Symptoms
Placeholder: IgE coats mast cells but no allergen is present to trigger reaction.
- IgE-bound: Mast cell coating (Placeholder sub-note)
- none: Clinical symptoms (Placeholder sub-note)
- sIgE test: Detectability (Placeholder sub-note)
- primed: Risk state (Placeholder sub-note)
Primed but asymptomatic state
Placeholder: sensitization can persist silently until re-exposure occurs.
Second Exposure Triggers Allergic Reaction
Placeholder: repeat allergen contact cross-links IgE and triggers degranulation.
- IgE-FcεRI: Cross-linking (Placeholder sub-note)
- histamine: Mediator release (Placeholder sub-note)
- minutes: Reaction onset (Placeholder sub-note)
- mild–anaphylaxis: Severity range (Placeholder sub-note)
Mast cell degranulation cascade
Placeholder: cross-linked IgE receptors trigger rapid histamine release.
Placeholder: repeat exposure risk depends on sensitization level and allergen type.