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

Abstract

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/cm² for 7 min of exposure).

Results:

Changes of the total atheroma volume (TAV; mm³) 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.