title: The antibody targeting the E314 peptide of human Kv1.3 pore region serves as a novel, potent and specific channel blocker.
abstract: Selective blockade of Kv1.3 channels in effector memory T (T(EM)) cells was validated to ameliorate autoimmune or autoimmune-associated diseases. We generated the antibody directed against one peptide of human Kv1.3 (hKv1.3) extracellular loop as a novel and possible Kv1.3 blocker. One peptide of hKv1.3 extracellular loop E3 containing 14 amino acids (E314) was chosen as an antigenic determinant to generate the E314 antibody. The E314 antibody specifically recognized 63.8KD protein stably expressed in hKv1.3-HEK 293 cell lines, whereas it did not recognize or cross-react to human Kv1.1(hKv1.1), Kv1.2(hKv1.2), Kv1.4(hKv1.4), Kv1.5(hKv1.5), KCa3.1(hKCa3.1), HERG, hKCNQ1/hKCNE1, Nav1.5 and Cav1.2 proteins stably expressed in HEK 293 cell lines or in human atrial or ventricular myocytes by Western blotting analysis and immunostaining detection. By the technique of whole-cell patch clamp, the E314 antibody was shown to have a directly inhibitory effect on hKv1.3 currents expressed in HEK 293 or Jurkat T cells and the inhibition showed a concentration-dependence. However, it exerted no significant difference on hKv1.1, hKv1.2, hKv1.4, hKv1.5, hKCa3.1, HERG, hKCNQ1/hKCNE1, L-type Ca(2+) or voltage-gated Na(+) currents. The present study demonstrates that the antibody targeting the E314 peptide of hKv1.3 pore region could be a novel, potent and specific hKv1.3 blocker without affecting a variety of closely related K(v)1 channels, KCa3.1 channels and functional cardiac ion channels underlying central nervous system (CNS) disorders or drug-acquired arrhythmias, which is required as a safe clinic-promising channel blocker.
authors.affiliation: Department of Cardiology, Union Hospital, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Xiao-Fang
authors.initials: XF
authors.lastname: Yang
authors.forename: Yong
authors.initials: Y
authors.lastname: Yang
authors.forename: Yi-Tian
authors.initials: YT
authors.lastname: Lian
authors.forename: Zhao-Hui
authors.initials: ZH
authors.lastname: Wang
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Li
authors.forename: Long-Xian
authors.initials: LX
authors.lastname: Cheng
authors.forename: Jin-Ping
authors.initials: JP
authors.lastname: Liu
authors.forename: Yan-Fu
authors.initials: YF
authors.lastname: Wang
authors.forename: Xiang
authors.initials: X
authors.lastname: Gao
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Liao
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Qiu-Tang
authors.initials: QT
authors.lastname: Zeng
authors.forename: Kun
authors.initials: K
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D000906:Antibodies / Q000276:immunology* / Q000494:pharmacology*; D000918:Antibody Specificity; D005110:Extracellular Space / Q000378:metabolism; D005260:Female; D057809:HEK293 Cells; D006801:Humans; D019169:Jurkat Cells; D051664:Kv1.3 Potassium Channel / Q000037:antagonists & inhibitors* / Q000737:chemistry* / Q000235:genetics / Q000276:immunology; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000276:immunology*; D016062:Porosity; D026902:Potassium Channel Blockers / Q000276:immunology / Q000494:pharmacology; D055550:Protein Stability
chemical_list: D000906:Antibodies; D051664:Kv1.3 Potassium Channel; D010446:Peptide Fragments; D026902:Potassium Channel Blockers