Transplantation of Fibroblast Sheets with Blood Mononuclear Cell Culture Exerts Cardioprotective Effects by Enhancing Anti-Inflammation and Vasculogenic Potential in Rat Experimental Autoimmune Myocarditis Model

Abstract

Fulminant myocarditis causes impaired cardiac function, leading to poor prognosis and heart failure. Cell sheet engineering is an effective therapeutic option for improving cardiac function. Naïve blood mononuclear cells (MNCs) have been previously shown to enhance the quality and quantity of cellular fractions (QQMNCs) with anti-inflammatory and vasculogenic potential using the one culture system. Herein, we investigated whether autologous cell sheet transplant with QQMNCs improves cardiac function in a rat model with experimental autoimmune myocarditis (EAM). Fibroblast sheets (F-sheet), prepared from EAM rats, were co-cultured with or without QQMNCs (QQ+F sheet) on temperature-responsive dishes. QQ+F sheet induced higher expression of anti-inflammatory and vasculogenic genes (Vegf-b, Hgf, Il-10, and Mrc1/Cd206) than the F sheet. EAM rats were transplanted with either QQ+F sheet or F-sheet, and the left ventricular (LV) hemodynamic analysis was performed using cardiac catheterization. Among the three groups (QQ+F sheet, F-sheet, operation control), the QQ+F sheet transplant group showed alleviation of end-diastolic pressure–volume relationship on a volume load to the same level as that in the healthy group. Histological analysis revealed that QQ+F sheet transplantation promoted revascularization and mitigated fibrosis by limiting LV remodeling. Therefore, autologous QQMNC-modified F-sheets may be a beneficial therapeutic option for EAM.

De novo Biological Coronary Artery Bypass in a Rat Model: Case Report and the Concept of Hybrid Cardiovascular Regeneration

“…Such arterial graft in contact with the ischemic myocardium may provide potent arterial support to the target distal arteries and/or regenerated arterioles, which are otherwise inaccessible by the current vascular procedures [6][7][8][9][10] . Since complete revascularization is not always achievable 13 , a combination of vascular approaches to provide proximal arterial inflow and mesenchymal progenitor cells [16][17][18][19] , including RACs infusion [20][21][22][23][24][25] , to regenerate distal vasculature and the myocardium may be attractive for revascularizing ischemic lesions, regenerating cardiomyocytes, and reinstating cardiac function.…”

“…Biologically, endothelial progenitor cells were isolated from peripheral blood 20 , were greatly expanded more than 200 times by quality and quantity control culture in vitro [21][22] , and were experimentally tested in skin defects 23 , autoimmune myocarditis 24 , and induced MI models 25 . Since RACs contain a sizable fraction of type 2 macrophages 29 , they migrate to locations of inflammation as homing characteristics.…”

“…After these functional studies, the whole heart was excised and submitted to morphological studies by Hematoxylin-Eosin and Trichrome staining. Immunohistochemical studies were performed using monoclonal antibody against myoglobin, CD31 and CD34 [21][22][23][24][25] .…”

“…Mesenchymal stem cells are different in that they were reported to possess homing capabilities, tolerance to allogeneic response 17 , and in situ differentiation 18 to promote angiogenesis and cardiomyogenesis [16][17][18][19] . Among them are the peripheral blood mononuclear cellderived and in vitro-expanded progenitor cells 20 , i.e., quality and quantity control culture cells [21][22][23][24] or regeneration-associated cells (RACs) 25 , which may function by migrating to tissues with inflammation irrespective of vascular size, and by expediting their anti-inflammatory as well as pro-regenerative activity [21][22][23][24][25] . In particular, RAC therapy early rather than late after coronary events may enhance its homing efficacy due to accentuated inflammation and intensify vasculogenesis and myocardial regeneration in the target lesions [8][9][10][11][12] .…”

“…These unique functions may allow intravenous administration to otherwise inaccessible ischemic lesions in order to stabilize inflammation, and revascularize as well as regenerate the myocardium [21][22] . Such functions have been tested via intramyocardial injection 22 , topical application [23][24] , or intravenous administration 25 . Herein, we report a representative case that substantiated the concept of "biological revascularization" of the ischemic myocardium, from which we obtained clues regarding further enhancement of efficacy in terms of surgical modifications, biological manipulations, and their combination with the current coronary vascular procedures.…”