HsTX1 (TFA)

HsTX1 (TFA) toxin, from the scorpion Heterometrus spinnifer, is a 34-residue, C-terminally amidated peptide cross-linked by four disulfide bridges. HsTX1 (TFA) is an the inhibitor of potassium channel, with IC50 for Kv1.3 of 12 pM and inhibits TEM cell activation and attenuates inflammation in autoimmunity[1][2][3].

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[1]M Harunur Rashid, et al. A potent and Kv1.3-selective analogue of the scorpion toxin HsTX1 as a potential therapeutic for autoimmune diseases. Sci Rep. 2014 Mar 28:4:4509. doi: 10.1038/srep04509.|[2]Mark R. Tanner, et al. Prolonged immunomodulation in inflammatory arthritis using the selective Kv1.3 channel blocker HsTX1[R14A] and its PEGylated analog. Immunol. 2017 Jul; 180: 45–57. Published online 2017 Apr 4.|[3]Lebrun, Bruno, et al. A four-disulphide-bridged toxin, with high affinity towards voltage-gated K+ channels, isolated from Heterometrus spinnifer (Scorpionidae) venom. Biochemical Journal. 328 (Pt 1): 321–327.