Cell-surface ultrastructural changes during the in vitro neuron-like differentiation of rat bone marrow-derived mesenchymal stem cells

Antlerogenic stem cells: molecular features and potential in rabbit bone regeneration

AIM

(i) To assess the expression profiles of stem cell-associated markers including Oct4, Sox2, Klf4, Nanog, C-myc, Stat3 and Cd9, (ii) analyze the nanotopography of the MIC-1 stem cells and (iii) evaluate the efficiency of live stem cell implants and stem cell culture derivatives on the regeneration of bone deficiencies in rabbit mandibles.

MATERIALS AND METHODS

The expression profiles of stem cell-associated genes, including Oct4, Sox2, Klf4, Nanog, C-myc, Stat3 and CD9 were assessed using reverse transcription polymerase chain reaction and flow cytometry. Nanotopography of the antlerogenic MIC-1 cell lineage was analyzed using atomic force microscopy. The effect of MIC-1 stem cells, their homogenate and supernatant on the regeneration of bone deficiencies in rabbit mandibles was evaluated using histological analysis. The effect of MIC-1 stem cells and stem cell-based derivatives on the immune responses of the animals was assessed by analyses of acute phase protein levels (haptoglobin and fibrinogen).

RESULTS

We found that the MIC-1 cells isolated from the apical regions of growing antlers exhibited molecular features that were characteristics of pluripotent stem cells. Using atomic force microscopy, we determined the details of the cell surface morphologies with a particular emphasis on the patterns of formation of plasma extensions for interlinking adjacent cells. We also demonstrated that not only implanted stem cells but also cell homogenates and cell post-culture supernatants have potential in the regeneration of bone deficiencies in the rabbit mandible.

CONCLUSIONS

Our findings indicate that the use of both antlerogenic stem cell implants and the preparations derived from the cells offer alternative approaches to those based on autologous stem cells in the biological stimulation of osteogenesis and in bone regeneration.

The effect of Bcl-2 siRNA combined with miR-15a oligonucleotides on the growth of Raji cells

Bcl-2 is a prominent member of the Bcl-2 family of proteins that regulate the induction of apoptosis. Here, we investigated the effect of Bcl-2 small interfering RNA (siRNA) combined with miR-15a oligonucleotides (ODN) on the growth of Raji cells. The expression levels of Bcl-2 mRNA and protein were detected. The inhibition of cell growth and apoptosis was determined. Atomic force microscopy was utilized to observe the cell-surface ultrastructural changes. After transfection of combination, protein and mRNA levels of Bcl-2 obviously were decreased. The growth of cells was significantly inhibited compared with those cells transfected with Bcl-2 siRNA or miR-15a alone. Apoptotic rate significantly increased. The cells of apoptosis showed a roughness variation on cell membranes. These results suggest that the combination of Bcl-2 siRNA and miR-15a ODN increases apoptosis in Raji cells. Our study implies that the combination of Bcl-2 siRNA and miR-15a may be a useful approach in treatment for lymphoma.

Detection of erythrocytes in patient with iron deficiency anemia using atomic force microscopy

PURPOSE

Iron deficiency anemia (IDA) disturbs the morphology and function of erythrocytes at molecular level. The purpose of this study was to show that pathophysiological changes to erythrocytes could be detected at the nanometer scale, which is important for the early diagnosis and effective therapies of the anemia.

METHODS

Blood samples were taken from six healthy volunteers and six patients with IDA before and after therapy. Changes in the morphological and biomechanical properties of erythrocytes were studied at the nanometer level using atomic force microscopy (AFM).

RESULTS

There were dramatic overall shape and surface membrane deformations of the erythrocytes associated with pre- and post-therapeutic IDA compared with healthy erythrocytes. Healthy and pathological erythrocytes of IDA could be distinguished by the morphologic parameters of width, length, the ratio of length to width, valley, peak, valley-to-peak, standard deviations, and surface fluctuation. Treatment effectiveness also could be evaluated by these parameters.

CONCLUSIONS

AFM is a good tool for IDA study. Erythrocyte morphology is an important determinant for diagnosing and evaluating therapeutic effect of IDA disease.