title: Antibodies to the extracellular pore loop of TRPM8 act as antagonists of channel activation.
abstract: The mammalian transient receptor potential melastatin channel 8 (TRPM8) is highly expressed in trigeminal and dorsal root ganglia. TRPM8 is activated by cold temperature or compounds that cause a cooling sensation, such as menthol or icilin. TRPM8 may play a role in cold hypersensitivity and hyperalgesia in various pain syndromes. Therefore, TRPM8 antagonists are pursued as therapeutics. In this study we explored the feasibility of blocking TRPM8 activation with antibodies. We report the functional characterization of a rabbit polyclonal antibody, ACC-049, directed against the third extracellular loop near the pore region of the human TRPM8 channel. ACC-049 acted as a full antagonist at recombinantly expressed human and rodent TRPM8 channels in cell based agonist-induced 45Ca2+ uptake assays. Further, several poly-and monoclonal antibodies that recognize the same region also blocked icilin activation of not only recombinantly expressed TRPM8, but also endogenous TRPM8 expressed in rat dorsal root ganglion neurons revealing the feasibility of generating monoclonal antibody antagonists. We conclude that antagonist antibodies are valuable tools to investigate TRPM8 function and may ultimately pave the way for development of therapeutic antibodies.
authors.affiliation: Department of Neuroscience, Amgen Inc., Thousand Oaks, California, United States of America.
authors.forename: Silke
authors.initials: S
authors.lastname: Miller
authors.affiliation: Department of Neuroscience, Amgen Inc., Thousand Oaks, California, United States of America.
authors.forename: Sara
authors.initials: S
authors.lastname: Rao
authors.affiliation: Department of Neuroscience, Amgen Inc., Thousand Oaks, California, United States of America.
authors.forename: Weiya
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Neuroscience, Amgen Inc., Thousand Oaks, California, United States of America.
authors.forename: Hantao
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Neuroscience, Amgen Inc., Thousand Oaks, California, United States of America.
authors.forename: Judy
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Neuroscience, Amgen Inc., Thousand Oaks, California, United States of America.
authors.forename: Narender R
authors.initials: NR
authors.lastname: Gavva
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D016466:CHO Cells; D002460:Cell Line; D003080:Cold Temperature; D003412:Cricetulus; D005727:Ganglia, Spinal / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D006930:Hyperalgesia / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D050053:TRPM Cation Channels / Q000037:antagonists & inhibitors* / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D050053:TRPM Cation Channels