All of the following are pa of innate immunity except:

Ans. (d) T cells Ref Harrison 17/e; p 2021, 2031, 18/e, p 2651. 2668 Components of the Adaptive Immune System Cellular Thymus-derived (T) lymphocytes - T cell precursors in the thymus; naive mature T lymphocytes before antigen exposure; memory T lymphocytes after antigen contact; helper T lymphocytes for B and T cell responses; cytotoxic T lymphocytes that kill pathogen- infected target cells. Humoral Bone-marrow-derived (B) lymphocytes - B cell precursors in bone marrow; naive B cells prior to antigen recognition; memory B cells after antigen contact; plasma cells that secrete specific antibody. Cytokines Soluble proteins that direct focus and regulate specific T versus B lymphocyte immune responses. Major Components of the Innate Immune System Pattern recognition receptors(PRR) C type lectins, leucine-rich proteins, scavenger receptors, pentraxins, lipid transferases; integrins Antimicrobial peptides a-Defensins, 8-defensins, cathelin, protegrin, granulysin, histatin, secretory leukoprotease inhibitor, and probiotics Cells Macrophages, dendritic cells, NK cells, NK-T cells, neutrophils, eosinophils, mast cells, basophils, and epithelial cells. Complement components Classic and altAutocrine, paracrineernative complement pathway, and proteins that bind complement components Cytokines Autocrine, paracrine, endocrine cytokines that mediate host defence and inflammation, as well as recruit, direct, and regulate adaptive immune responses