Abstract :
Microbial agents like bacteria, viruses and fungi have surface coating molecules, which have a discrete molecular pattern for each organism, specifically known as PAMP, Pathogen Associated Molecular Pattern. A whole bacterium or the envelope of a virus expresses several PAMPs. They interact with Pattern Recognition Molecules (PRMs) expressed on the surfaces of immune defence cells like macrophages, neutrophils and NK cells. The PRMs include the scavenger receptors of macrophages, mannose receptors, CD14 binding molecule for LPS on monocytes, macrophages and PMNs, NK cell activating receptors as well as the Toll-Like Receptors (TLRs). Originally, the Toll-gene was identified as a receptor for anti-fungal immunity in Drosophila.
