Table 5 Microglial and neuropathic pain-related gene expression

ABCA1

Y

Y

Transporter of cholesterol and other lipids

AIF1

Y

Y

Forms complexes with L-fimbrin in membrane ruffles and phagocytic cups; may modulate actin reorganization, facilitates cell migration and phagocytosis

ANXA3

Y

Y

Annexin family member; up-regulated following tissue injury

ATF3

Y

Y

Complexes with other transcriptional regulators; up-regulated in response to injury; negative regulator of TLR signaling; suppresses innate immune response

BLNK

Y

Cytoplasmic linker protein important in B cell development

C1QA

Y

Y

Part of C1q complex; initial component of classic pathway

C1QB

Y

Y

Part of C1q complex

C1QC

Y

Y

Part of C1q complex

C4A

Y

Y

Cleaved by C1S; combines with C2 cleavage product forms C4b2b complex

CAMK2B

Y

Y

Ca2+/calmodulin-dependent protein kinase

CD163

Y

M2 state microglial marker (aka, ED2); Alt priming gene

CD37

Y

Y

Interacts with dectin; regulates PAMP induced IL6 production; microglial sensome

CD53

Y

Y

Contributes to transduction of CD2-generated signals in T cells

CD74

Y

Y

Invariant MHCII component; processes receptor bound PAMP’S and DAMP’s for presentation to T cells

CSF3R

Y

Y

Binds GCSF, which increases M2 state marker expression, and inhibits pro-inflammatory cytokine expression, while promoting neurotrophic factor expression.

CXCL9

Y

Y

Ligand for Cxcr3 receptor, activated by TLR ligands and pro-inflammatory cytokines; appears to regulate T cell migration

Egr2

Y

Transcription factor; Alt priming gene

EMR1

Y

Y

Member of adhesion GPCR receptors; required to activate CD8+ regulatory T cells

FAM105A

Y

Y

FCER1G

Y

Y

High affinity Fc epsilon receptor; binds TREM2; involved in response to apoptotic debris, immune complexes through C1q complex

FCGR2B

Y

Y

Fc receptor, IgG, low affinity; binds Cxcl7 (CD32B); inhibitory

FCGR3A

Y

Y

Aka CD16a; similar to FCGR2B

FCRLS

Y

Fc immunoglobulin receptor; part of TGFb1 microglial signature response

GOLM1

Y

Assists transport of cargo through Golgi apparatus; AD risk gene

IGF1

Y

Neurotrophic factor; increased by IL4/MCSF; M2 phenotype and Alt priming gene

IGFBP6

Y

Y

Binds IGF’s and modulates their growth factor effects

ITGB2

Y

Y

CD18; integrin beta chain beta 2; involved in leukocyte adhesion

LGALS3

Y

Galectin family; inflammatory factor (MAC2); microglial marker; Alt priming gene

PTPRC

Y

Y

Protein tyrosine phosphatase; aka CD45; enriched in microglia; opposes microglial activation

PYCARD

Y

Y

Mediator of apoptosis and inflammation; adapter for inflammasome assembly

TLR7

Y

Y

TLR (nucleotide sensing); signals via MyD88 pathway; can modulate other TLR’s

TMEM173

Y

Y

Facilitates innate immune signaling; promotes expression of IFN-alpha and IFN-beta;

TREM2

Y

Forms signaling complex with TYROBP; M2 state and sensome gene; promotes microglial expansion; up-regulated by IL4; critical for normal phagocytosis

TYROBP

Y

Y

Forms signaling complex with TREM2; activates microglia; required for synaptic pruning