Humanized Endothelial Specific TRPC3 Transgenic Mouse

Project: D2012-18

Strains: EST3Tg/C57BL6 and EST3Tg/Apoe^-/-

Type: Humanized transgenic mouse

Background: In the U.S., atherosclerosis, hypertension and stroke are the major causes of death due to cardiovascular disease and remain most frequent vascular complications of metabolic diseases such as diabetes, obesity and metabolic syndrome. A common signature of the associated vascular pathology is the presence of a dysfunctional endothelium, endothelial inflammation and/or changes in endothelial integrity. Research over the last fifteen years led to identification of members of the Transient Receptor Potential Canonical (TRPC) family of channel forming proteins as key components of signaling processes in cardiovascular disease. In particular, TRPC3 plays a pivotal role in several events linked to changes in endothelial permeability, endothelial inflammatory signaling, and expression of endothelial cell adhesion molecules and regulation of nitric oxide production, among others. Whereas a great deal of information on the potential roles of TRPC3 in those processes has been obtained from in vitro and ex vivo models, lack of endothelial-specific in vivo models with gain or loss of TRPC3 function has severely limited our ability to validate in vitro findings or to examine the impact of pharmacological targeting of TRPC3 on disease onset and/or progression.

Invention description: This invention provides a unique in vivo model to study the role of the human TRPC3 channel in the vascular pathology associated to a number of cardiovascular and metabolic diseases that course with endothelial dysfunction, endothelial inflammation and/or changes in endothelial integrity. This new humanized endothelial-specific TRPC3 transgenic mouse provides a “gain-of-function” in vivo model to examine the role/s of TRPC3 channel activity and/or TRPC3-dependent signaling in atherosclerosis, hypertension, type II diabetes, metabolic syndrome, obesity, all diseases in which alterations in endothelial function represents a typical vascular feature throughout all disease stages.

Researchers at the University of Toledo have generated a mouse model designated EST3Tg (“Endothelial Specific TRPC3 Transgenic) which carries endothelial-specific overexpression (transgenic) of the human form of TRPC3. The EST3Tg mouse was generated by microinjection of mouse oocytes with a cDNA construct encoding human TRPC3 tagged in its C-terminal end with the hemagglutinin epitope (HA) to allow discrimination between the human protein and the endogenous mouse protein by means of western-blot, immunohistochemistry or genotyping. Expression of this construct is driven by the Flt-1 promoter which ensures endothelial specific expression with no leakage in hematopoietic cells, a common issue with other endothelial promoters (v.g., cadherin-5 or Tie2). Following characterization and expansion of founder colonies, UT researchers intercrossed EST3Tg mice with C57BL/6 and ApoE-deficient (on C57BL/6 background) mice (EST3TgC57BL/6 and EST3TgApoE^-/-, respectively). Availability of the EST3Tg mouse in these two backgrounds expands tremendously the research applicability of this new in vivo model to a variety of cardiovascular and metabolic diseases.    

Patent Status:  Tangible Property