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Toll-like receptors (TLRs) and mannan-binding lectin (MBL): On constant alert in a hostile environment

By Ingrid-Maria Bergman

Abstract

In the beginning were neither B cells nor T cells nor antibodies, but innate immune defense alone. The primary functional theme of innate immunity is the distinction between self and non-self, which is maintained by a vast number of cellular and subcellular components. In this context, the immense importance of the Toll-like receptors (TLRs) is well established. Positive (Darwinian) selection seems to be acting on the ligand-binding domains of these molecules, suggesting a selection pattern similar to that previously observed in the MHC proteins. In sharp contrast to TLRs, the biological significance of mannan-binding lectin (MBL) is controversial, and, concerning humans, it has been suggested that low concentration of MBL in serum represents a selective advantage. In this mini-review, based on a doctoral thesis, evolutionary aspects of TLRs and MBL are discussed

Topics: Review Article
Publisher: Informa Healthcare
OAI identifier: oai:pubmedcentral.nih.gov:3078537
Provided by: PubMed Central
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