Stimulation of angiogenesis in rat ischemic limb by intramuscular implantation of mononuclear fraction cells from autologous bone marrow.

We studied angiogenic effects of two variants of indirect revascularization (transplantation of mononuclear fraction cells from autologous bone marrow alone or in combination with laser tunneling) after modeled ischemia of the lower limbs in rats. Doppler sonography and immunofluorescence studies showed that intramuscular implantation of isolated fraction of autologous bone marrow mononuclear cells in combination with laser tunneling of the muscles is most effective and can be recommended as a method of angiogenesis stimulation in non-reconstructable distal vascular pathology of the extremities.

Morphological and molecular analysis of angiogenesis after intramyocardial transplantation of autologous bone marrow mononuclear cells.

We studied the peculiarities of angiogenesis in the postinfarction period after transmyocardial laser revascularization and intramyocardial implantation of mononuclear bone marrow cells into the pericicatrical zone of the left ventricular myocardium in dogs. Morphological manifestation of angiogenesis in the myocardium after application of laser and cell technologies are angiomatosis, formation of large thin-wall vessels and sinusoids. The angiogenic effect of implanted mononuclear bone marrow cells is determined by high content (43-47%) of CD31+ cells in both adherent and nonadherent fractions. More pronounced angiogenic potential of nonadherent cells is determined by intensive expression of cytokine VEGF-B and D mRNA essential for arterial vessels growth. Immunohistochemical studies showed that about 90% cells of the nonadherent fraction are endothelial precursors expressing endothelial cell markers isolectin B4 and VEGF-R2. It was found that the use of adherent mononuclear bone marrow cells during the postinfarction period induces ossification of the epicardium and subepicardial myocardium layer, formation of cartilage plates, and focal calcification. Implantation of nonadherent mononuclear bone marrow cells into transmyocardial laser channels did not induce ectopic ossification of the myocardium.

Structural and molecular reorganization of cardiomyocytes in transposition of the main vessels.

Studies of myocardial autopsy specimens from infants (0-12 months) with transposition of the main vessels showed the formation of a complex of compensatory adaptive, degenerative, and destructive changes, manifesting at a tissue level in cardiomyocyte heterogeneity and formation of cardiosclerosis zones. Cardiac myosin synthesis was replaced by synthesis of skeletal myosin, which was detected at the molecular level. Clinically it manifested in the progress of heart failure. Hyperplastic processes (intensive polyploid transformation of the nuclei) play an important role in heart remodeling in patients aged over 6 months. The findings of immunohistochemical and fluorescent studies seem to be prognostically important and provide more accurate data on the pathological processes in the myocardium at the initial stages of heart disease development starting from birth.

Angiomatosis and ectopic ossification in the dog myocardium after intramyocardial implantation of autologous bone marrow mononuclears in experimental coronary disease.

Disseminated ossification of the myocardium and severe angiomatosis were detected in sites of implantation of unseparated bone marrow mononuclear fraction cells in dogs with experimental chronic coronary disease. Minor immunocytochemical differences in cells of the mononuclear fraction adhering and not adhering to plastic were found. Significant differences in the expression of mRNA of chondro-osteogenesis genes (aggrecan, lumican, and osteopontin) in adherent and nonadherent cells were detected. The expression of aggrecan gene mRNA was 3-fold lower, of lumican gene 6-fold, and of osteopontin gene 11-fold lower in nonadherent cells compared to adherent fraction.

Morphological evaluation of cytoarchitectonics of aortic graft at the biotechnological stage with analysis of changes in laser-induced fluorescence spectra.

We performed a fluorescent microscopic examination of human and animal aortic grafts at different stages of decellularization. Treatment of aortic grafts with trypsin/EDTA solution for 48 h leads to their complete decellularization and preserved the connective tissue fiber backbone, which gains a netlike structure. The use of this protocol of decellularization leads to disappearance of subintimal calcium deposits in human aortic grafts. Differences in laser-induced fluorescence spectra of aortas before decellularization and at different stages of this process were revealed. Our findings suggest that the use of fluorescence induced by excimer lasers is promising for identification of the composition of biological tissues, analysis of their state, and the presence of changes.