Plasmonic Photothermic and Stem Cell Therapy of Atherosclerotic Plaque As a Novel Nanotool for Angioplasty and Artery Remodeling

Background: Some modern angioplasty techniques drastically affect the geometry of the plaque and the lumen, but have some inherent clinical and technical limitations. Methods: A total of 101 Yucatan miniature swine were allocated to the three following groups (34 pigs into 60/15- to 70/40-nm silica-gold nanoparticles (NPs), 34 swine into ferromagnetic group with iron-bearing NPs and delivery in hand of magnetic fields, and 33 in a sirolimus stenting control). Animals in the nanogroup were subdivided further into four subsets according to the delivery approach: (1) Intracoronary infused circulating stem progenitor cells (SPCs), including SP+ (side population) cells, (2) intracoronary infused, ultrasound-mediated, albumin-coated, gas-filled microbubbles, (3) CD73(+)105(+) SPCs in the composition of a bioengineered on-artery patch (cardiac surgery), (4) CD73(+)CD105(+) SPCs engrafted by manual subadventitial injection (cardiac surgery). NPs were detonated with a microwatt near-infrared (NIR) laser (821 nm, 35-44 W/cm(2) for 7 min of exposure). Results: Changes of the total atheroma volume (TAV; mm(3)) immediately after the laser irradiation at month 6 in the nanoshell, ferromagnetic, and control groups were -7.54%/-22.92%, -9.7%/-16.84%, and -10.5%/-7.06% (p < 0.01), respectively, and in the subsets reached -2.79%/-21.92%, -6.26%/-15.24%, -4.6%/-31.21%, -16.5%/-23.3% (p < 0.05), respectively. Some cases of atherothrombosis and distal embolism (23.5%) were documented only in the microbubbles subset. The impact of the therapy on the nonorganic part of the plaque-antiinflammative and antiapoptotic effects, signs of neovascularization, and restoration of artery function-were predominant in the observed subsets with SPCs (p < 0.01). Conclusion: Nanoburning, especially in combination with stem cell technologies, is a very challenging technique for altering advanced plaque and holds the promise of revolutionizing state-of-the-art interventional cardiology, assuring destruction of plaque and functional restoration of the vessel wall. It could potentially become the current mechanical and pharmacological treatment.