ACAAI Review for the Allergy and Immunology Boards - American ...

IMMUNE MECHANISMS / 65Table 1-30. Innate Immune MechanismsBacteriaFungiVirusesParasitesMicrobeExtracellularIntracellularComplement activation;Phagocytosis: recognition by PRRImmune MechanismsNucleotide binding oligomerization domain-like receptors (NLRs)Neutrophil phagocytosis;Complement ActivationPhagocytosis: Toll-like receptors (TLRs) and NK cellsPhagocytosis;Complement (alternate pathway)Table 1-31. Innate Versus Adaptive Immune MechanismsInnate ImmunityAdaptive ImmunityGenetics Response encoded in host germ line DNA Somatic gene rearrangementRecognitionComponentsRecognize conserved sequences such aspathogen-associated molecular patterns(PAMPs)Complement;Pattern recognition receptors (PRRs) onimmune cellsPhagocytesMast cell or BasophilsNK CellsRecognize unique antigenicdeterminants:TCR and (MHC restricted-)Ig receptorsT lymphocytes, B lymphocytes, andcomplementComponentsAntimicrobial Peptides—Antimicrobial peptides (AMP) are ubiquitous cationicproteins that play a role in innate immunity. They provide defense against bacteria andfungi viruses.Features:Produced by keratinocytesTwo families in humans:o Human β Defensins: HBD1, 2, 3o Human Cathelicidins: LL37o Lactoferrins: hLF1-11o HistatinsInteract with phospholipids of microbial membranes, enter cell and mediateantiproliferative effects.