TLR9 and allergic bronchopulmonary aspergillosis: Binding to these receptors, triggers secretion of pro-inflammatory cytokines, and TLR activation on dendritic cells causes propagation of an adaptive immune response.48 Genetic polymorphisms in TLR3 and TLR9 and mannose binding lectin have been shown to cause susceptibility to ABPA, and TLR agonists have been considered as adjuvants in allergy immunotherapy treatment including in ABPA.48, , –51