Table 1.

The role of SLC transporters in RA cells other than FLS.

SLC family	Gene	Alias	Substrates	Cell type	Findings	Reference
SLC2	SLC2A1 SLC2A2	GLUT1 GLUT2	DHA, glucose, galactose, mannose, glucosamine	Chondrocytes	DHA transported via GLUT1 regulated by hypoxia	(69)
SLC5	SLC5A12	SMCT2	Short chain fatty acids	CD4+ T cells	Lactate regulates T-cell migration and regulates metabolism and inflammation	(70), (47)
SLC7	SLC7A5	LAT1	Large neutral AA	Monocytes Macrophages	Glycolytic reprogramming through SLC7A5 in immune response	(71)
SLC7	SLC7A11	XC-	Cysteine, glutamate	Endothelial cells	Sulfasalazine inhibits fibroblast growth-factor induced chemotaxis of endothelial cells	(72)
SLC16	SLC16A1	MCT1	Lactate, pyruvate, ketone bodies	T cells	Lactate regulates T-cell migration and regulates metabolism and inflammation	(70)
SLC29	SLC29A1	ENT1	Nucleoside	T cells in animal model	Decitabine therapy results in long-term remission of RA	(72)
SLC29	SLC29A1 SLC29A2	ENT1 ENT2	Nucleoside	Mixed synovial cells	Dipyridamole is an ENT inhibitor. It did not affect cytokine release in RA and OA cells	(73)
SLC38	SLC38A1 SLC38A2 SLC38A3	SNAT1 SNAT2 SNAT4	Gln, Ala, Asp, Cys, His, Ser	Monocytes Neutrophils AIA	Glutamine uptake is regulated by SNAT and attenuated AIA	(74)
SLC39	SLC39A8	ZIP8	Zinc	Macrophages	Zinc regulated IL-1β	(75)
SLC63	SLC63A2	SPNS2	Sphingolipids	CIA model	SPNS2 deletion improved arthritis	(76)

CIA, collagen induced arthritis; AIA, antigen induced arthritis, AA, amino acids; GLUT, glucose transporter; SMCT2, sodium-coupled monocarboxylate transporters; LAT1, L-type amino acid transporter; MCT1, monocarboxylate transporter 1; ENT, Equilibrative nucleoside transporter; SNAT, Sodium-Coupled Neutral Amino Acid Transporter; ZIP, Zrt- and Irt-like proteins; SPNS2, Sphingolipid Transporter 2; DHA, Dehydroascorbate