Table 1.

Thyroid hormone transporters

Transporter1	Iodothyronine derivates	Specificity2	Reference
MCT8	T3, T4, rT3, T2	+++	17 18
MCT10	T3, T4	++	57
Oatp1a1	T3, T4, rT3, T2, T4S, T3S, rT3S, T2S	+	8
OATP1A2	T4, T3, rT3	+	102
Oatp1a3	T4, T3	+	103
Oatp1a4	T4, T3	+	7
Oatp1a5	T4, T3	+	7
OATP1B1	T4, T3, T3S, T4S, rT3S	+	67 104
Oatp1b2	T3, T4	+	105
OATP1B3	rT3, T4S, T3S, rT3S	+	13
OATP1C1	T4, rT3, T3, T4S	++	59
OATP2B1	T4	+	61
OATP3A1_v1/v2	T4	++	88
Oatp4a1	T3, T4, rT3	+	102
OATP4C1	T3, T4	+	86
Oatp6b1	T3, T4	+	106
Oatp6c1	T3, T4	+	106
LAT1	T3, T4, rT3, T2	+	77
LAT2	T3, T4, rT3, T2	+	77
NTCP	T4, T3, T4S, T3S	++	8 9
MDR1	T3	+	10

¹The human protein symbol is presented, if TH transport has been demonstrated in different species including humans.

²If a transporter only transports iodothyronine derivatives, specificity is high (+++). If fewer than five other ligands are known, specificity is moderate (++). If more than five ligands are known, the transporter is denoted as multispecific (+).