Function and phenotype of microglia are determined by toll-like receptor 2/toll-like receptor 4 activation sequence.
Toll-like receptors (TLRs) initiate and maintain host defenses. These receptors play important roles in innate immunity and in various diseases. Different TLRs bind to diverse ligands that trigger distinct protein expression patterns. Few studies have focused on the interaction between different TLRs. We found that TLR2 priming downregulates TLR4 transcription, and expression of TLR4 activation induced major histocompatibility complex II (MHC II), adhesion molecule intercellular adhesion molecule-1 (ICAM-1), phagocytosis marker CD11b/CD18, and Fcgamma receptor (FcgammaR) expression. In contrast, TLR4 priming increases TLR2 transcription and expression. In addition, TLR4 priming increases secretion of certain proinflammatory mediators. Expression of costimulatory molecules CD80/CD86 increases with TLR2 or TLR4 activation sequences. Our results reveal that TLR2/TLR4 activation may determine disease pathogenesis and prognosis.
Li
Weixin
W
Neurosurgical Department,Tangdu Hospital, Fourth Military Medical University , Xi'an, People's Republic of China .
Gao
Guodong
G
Guo
Qingdong
Q
Jia
Dong
D
Wang
Julei
J
Wang
Xuelian
X
He
Shiming
S
Liang
Qinchuan
Q
D000328:Adult; D001483:Base Sequence; D039481:CD11b Antigen / Q000096:biosynthesis; D018821:CD18 Antigens / Q000096:biosynthesis; D017931:DNA Primers; D015536:Down-Regulation; D024202:Electrophoretic Mobility Shift Assay; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis; D017628:Microglia / Q000502:physiology*; D010641:Phenotype; D011401:Promoter Regions, Genetic; D017452:Receptors, IgG / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051195:Toll-Like Receptor 2 / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D051197:Toll-Like Receptor 4 / Q000737:chemistry / Q000235:genetics / Q000502:physiology*
D039481:CD11b Antigen; D018821:CD18 Antigens; D017931:DNA Primers; D000949:Histocompatibility Antigens Class II; D017452:Receptors, IgG; C495342:TLR2 protein, human; C495345:TLR4 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D018799:Intercellular Adhesion Molecule-1