Article

Expanding the universe of cytokines and pattern recognition receptors: galectins and glycans in innate immunity.

Laboratorio de Inmunopatología, Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas, 1428 Buenos Aires, Argentina.
Journal of Clinical Immunology (impact factor: 3.08). 12/2010; 31(1):10-21. DOI:10.1007/s10875-010-9494-2 pp.10-21
Source: PubMed

ABSTRACT Effective immunity relies on the recognition of pathogens and tumors by innate immune cells through diverse pattern recognition receptors (PRRs) that lead to initiation of signaling processes and secretion of pro- and anti-inflammatory cytokines. Galectins, a family of endogenous lectins widely expressed in infected and neoplastic tissues have emerged as part of the portfolio of soluble mediators and pattern recognition receptors responsible for eliciting and controlling innate immunity. These highly conserved glycan-binding proteins can control immune cell processes through binding to specific glycan structures on pathogens and tumors or by acting intracellularly via modulation of selective signaling pathways. Recent findings demonstrate that various galectin family members influence the fate and physiology of different innate immune cells including polymorphonuclear neutrophils, mast cells, macrophages, and dendritic cells. Moreover, several pathogens may actually utilize galectins as a mechanism of host invasion. In this review, we aim to highlight and integrate recent discoveries that have led to our current understanding of the role of galectins in host-pathogen interactions and innate immunity. Challenges for the future will embrace the rational manipulation of galectin-glycan interactions to instruct and shape innate immunity during microbial infections, inflammation, and cancer.

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Keywords

anti-inflammatory cytokines
 
conserved glycan-binding proteins
 
current understanding
 
different innate immune cells
 
diverse pattern recognition receptors
 
galectin-glycan interactions
 
host invasion
 
host-pathogen interactions
 
innate immune cells
 
modulation
 
neoplastic tissues
 
pattern recognition receptors responsible
 
polymorphonuclear neutrophils
 
rational manipulation
 
Recent findings
 
selective signaling pathways
 
shape innate immunity
 
signaling processes
 
specific glycan structures
 
various galectin family members influence
 

Juan P Cerliani