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Objective: Dysfunctional angiogenesis is a pathogenetic marker of SSc. Circulating levels of endothelial progenitor cells are reduced, and mesenchymal stromal cells show a reduced differentiation into endothelial cells and capacity to form capillaries. This suggests that pathophysiologically relevant changes may already exist in SSc bone marrow (BM) stromal cells that may affect downstream angiogenesis. The aim of this study is to evaluate, in SSc BM, angiogenesis, cellular immune system and fibrosis., Methods: Eight SSc patients affected by a severe dcSSc and screened for autologous haematopoietic stem cells transplantation (HSCT) underwent a BM biopsy. BM biopsies were compared with six healthy controls. To evaluate angiogenesis and cellular immunity, the following antibodies were used: vascular endothelial growth factor (VEGF), kinase insert domain-containing receptor/fetal liver kinase-1 (KDR/flk-1), MMP-9 and CD34. To evaluate fibrosis, silver impregnation for reticulum was used. The number of vessels, the mean area of vascularization, the perimeter and microvessel density (MVD) were measured with a multiparametric computerized imaging analysis., Results: A significant reduction in BM vascularity was found, while VEGF expression was much higher in SSc BM samples. Two patients had a Grade 2, whereas another two had a Grade 1 fibrosis., Conclusion: In SSc, BM is characterized by a reduction of microvascular density and number of vessels and a significant increase of VEGF. This indicates that BM may be involved in the process of loss of angiogenesis, despite the presence of high local and systemic levels of VEGF.

Background Aims: Bone marrow (BM) is the most used source of hemopoietic stem cells (HSC) and mesenchymal stromal cells (MSC) in both hematologic settings and regenerative medicine. We compared the feasibility and reproducibility of two gravity separation techniques, with or without the use of a density gradient, in terms of both hematopoietic and mesenchymal human BM progenitors., Methods: A total of 16 BM samples was processed to obtain mononuclear cells (MNC) and buffy coats (BC). The efficiency of the two procedures was evaluated by recovery of white blood cells (WBC), MNC and CD34(+) cells, clonogenic assays, red blood cell (RBC) depletion, cell viability, expression of embryonic transcriptional regulators and MSC assessment., Results: The two procedures yielded a comparable recovery of HSC. Non-density gradient separation (NDGS) of BM resulted in four times higher MSC recovery and higher expression of embryonic stem cell markers (Nanog and Sox2) compared with density-gradient separation (DGS). MSC derived from both procedures was comparable in terms of phenotype, differentiation and proliferation potential., Conclusions: NDGS is less time consuming, provides a better MSC enrichment and appears to be a suitable cell preparation method for clinical applications.

Autologous haematopoietic stem cell transplantation (AHSCT) is increasingly used to treat people with multiple sclerosis (MS). Supported by an evolving evidence base, AHSCT can suppress active inflammation in the central nervous system and induce long-term changes in immune cell populations, thereby stabilizing, and, in some cases, reversing disability in carefully selected MS patients. However, AHSCT is an intensive chemotherapy-based procedure associated with intrinsic risks, including profound cytopenia, infection, and organ toxicity, accompanied by an on-going degree of immuno-compromise and general deconditioning, which can be associated with a transient increase in functional impairment in the early stages after transplantation. Although international guidelines and recommendations have been published for clinical and technical aspects of AHSCT in MS, there has been no detailed appraisal of the rehabilitation needed following treatment nor any specific guidelines as to how this is best delivered by hospital and community-based therapists and wider multidisciplinary teams in order to maximize functional recovery and quality of life. These expert consensus guidelines aim to address this unmet need by summarizing the evidence-base for AHSCT in MS and providing recommendations for current rehabilitation practice along with identifying areas for future research and development. [ABSTRACT FROM AUTHOR]

Objective To confirm CXCL10 over production in bone marrow mesenchymal stem cells ( MSCs) and circulating monocytes isolated from multiple sclerosis patients ( MS) and identify predate cell molecular signature; to extend this analysis after autologous hematopoietic stem cell transplantation ( AHSCT) to test if therapy has modifying effects on MSCs and circulating monocytes. Methods MSCs and monocytes were isolated from 19 MS patients who undergone AHSCT before and seven of them at least 3 years after transplant. CXCL10 production was detected after LPS/ IFN- γ stimulation. TLR4 signaling pathways were investigated by means of transcription factors phosphorylation/activation level. RT- PCR of activated transcription factors was performed to quantify their expression. All experiments were conducted in parallel with 24 matched healthy donors ( HD). Results CXCL10 expression was significantly increased in both peripheral circulating monocytes and BM MSCs compared to HD. We showed that CXCL10 production is determined by an altered signaling pathway downstream TLR4, with the involvement of STAT-1, NF- κB, p38, JNK, and CREB. All upregulated transcription factors are more phosphorylated in MS patient sample. These features are not modified after AHSCT. Interpretation We demonstrated that in MS two different cell lineages are characterized by significantly increased production of CXCL10, due to altered signaling pathways of innate immune reaction mediated by TLR4, probably associated with disease phenotype. This characteristic is not modified by AHSCT, suggesting that when T and B lymphocytes are reset, other possible components of MS pathology, such as CXCL10 over production, do not determine therapy outcome. [ABSTRACT FROM AUTHOR]

Mesenchymal stromal cells (MSCs) are the leading cell candidates in the field of regenerative medicine. These cells have also been successfully used to improve skeletal muscle repair/regeneration; however, the mechanisms responsible for their beneficial effects remain to be clarified. On this basis, in the present study, we evaluated in a co-culture system, the ability of bone-marrow MSCs to influence C2C12 myoblast behavior and analyzed the cross-talk between the two cell types at the cellular and molecular level. We found that myoblast proliferation was greatly enhanced in the co-culture as judged by time lapse videomicroscopy, cyclin A expression and EdU incorporation. Moreover, myoblasts immunomagnetically separated from MSCs after co-culture expressed higher mRNA and protein levels of Notch-1, a key determinant of myoblast activation and proliferation, as compared with the single culture. Notch-1 intracellular domain and nuclear localization of Hes-1, a Notch-1 target gene, were also increased in the co-culture. Interestingly, the myoblastic response was mainly dependent on the paracrine release of vascular endothelial growth factor (VEGF) by MSCs. Indeed, the addition of MSC-derived conditioned medium (CM) to C2C12 cells yielded similar results as those observed in the co-culture and increased the phosphorylation and expression levels of VEGFR. The treatment with the selective pharmacological VEGFR inhibitor, KRN633, resulted in a marked attenuation of the receptor activation and concomitantly inhibited the effects of MSC-CM on C2C12 cell growth and Notch-1 signaling. In conclusion, this study provides novel evidence for a role of MSCs in stimulating myoblast cell proliferation and suggests that the functional interaction between the two cell types may be exploited for the development of new and more efficient cell-based skeletal muscle repair strategies. [ABSTRACT FROM AUTHOR]

Background aims. The human mesenchymal stromal cell (hMSC), a type of adult stem cell with a fibroblast-like appearance, has the potential to differentiate along the mesenchymal lineage and also along other cell lineages. These abilities make hMSC a promising candidate for use in regenerative medicine. As the hMSC represents a very rare population in vivo, in vitro expansion is necessary for any clinical use. hMSC characterization is commonly carried out through the expression of specific markers and by the capability of differentiating toward at least adipo-, osteo- and chondrocytic lineages. Commitment processes also result in significant changes in the ultrastructure in order to acquire new functional abilities; however, few studies have dealt with the ultrastructural characteristics of hMSC according to the time of incubation and type of media. Methods. The immunophenotype, functional characteristics and ultrastructural features of bone marrow (BM) hMSC cultured in two different media were investigated. The media chosen were Iscove's modified Dulbecco's medium (IMDM) and the Dulbecco's modified Eagle medium (DMEM). The latter has been recommended recently by two international transplantation and cytotherapy societies, the International Society of Cellular Therapy (ISCT) and European Group for Blood and Bone Marrow Transplantation (EBMT), for hMSC expansion for clinical applications. Results and Conclusions. The present results indicate that culture conditions greatly influence hMSC ultrastructural features, proliferation, growth and differentiation. In particular, our findings demonstrate that DMEM preserves the hMSC stem features better. Furthermore, the results obtained in IMDM suggest that a small size does not always correlate with conditions of cell immaturity and a greater proliferative potential. [ABSTRACT FROM AUTHOR]

Sphincter injury is a common cause of anal incontinence. Surgical repair remains the operation of choice; however, the outcome often is poor. We investigated the ability of injected bone marrow-derived mesenchymal stem cells to enhance sphincter healing after injury and primary repair in a preclinical model. Twenty-four inbred Wistar Furth rats were divided into three groups. As a control, Group A underwent sham operation. Group B had sphincterotomy and repair of both anal sphincters plus saline injections. The study group (Group C) underwent sphincterotomy and repair followed by intrasphincteric injections of syngenic bone marrow-derived mesenchymal stem cells. A further group (Group D) of outbred Wistar rats treated with mesenchymal stem cells and immunosuppressive therapy also was evaluated. At 30 days, histologic and morphometric analysis and in vitro contractility testing was performed. A significant decrease of muscle tissue was observed at the site of repair after sphincter injury. However, in Groups C and D, histologic examination demonstrated new muscle fibers and morphometric analysis revealed a significantly greater muscle area fraction than in Group B ( P < 0.05). Moreover, mesenchymal stem cells injection improved contractility of sphincters strips compared with Group B ( P < 0.05). No significant differences were found between Groups C and D. In our experimental model, bone marrow-derived mesenchymal stem cells injection improved muscle regeneration and increased contractile function of anal sphincters after injury and repair. Therefore, mesenchymal stem cells may represent an attractive tool for treating anal sphincter lesions in humans. Investigations into the biologic basis of this phenomenon should increase our knowledge on underlying mechanisms involved in sphincter repair. [ABSTRACT FROM AUTHOR]

Recent studies indicate that mesenchymal stem cells (MSC) exhibit a degree of immune privilege due to their ability to suppress T cell mediated responses causing tissue rejection; however, the impact of allogeneic MSC in the setting of organ transplantation has been poorly investigated so far. The aim of our study was to evaluate the effect of intravenous donor MSC infusion for clinical tolerance induction in allogeneic skin graft transplantations in rats. MSC were isolated from Wistar rats and administered in Sprague-Dawley rats receiving Wistar skin graft with or without cyclosporine A (CsA). Graft biopsies were performed at day 10 post transplantation in all experimental groups for histological and gene expression studies. Intravenous infusion with donor MSC in CsA-treated transplanted rats resulted in prolongation of skin allograft survival compared to control animals. Unexpectedly, donor MSC infusion in immunocompetent rats resulted in a faster rejection as compared to control group. Cytokine expression analysis at the site of skin graft showed that CsA treatment significantly decreased pro-inflammatory cytokines IFN-γ and IL-2 and reduced TNF-α gene expression; however, the level of TNF-α is high in MSC-treated and not immunosuppressed rats. Results of our study in a rat tissue transplantation model demonstrated a possible immunogenic role for donor (allogeneic) MSC, confirming the need of adequate preclinical experimentation before clinical use. [ABSTRACT FROM AUTHOR]

There is considerable interest in an autologous transplantation (AT) programme for patients with high-risk breast cancer; however, the issue of the incidence of occult bone marrow (BM) micrometastasis at diagnosis, and the cancer contamination of peripheral blood stem cell (PBSC) collections used for haematological rescue, is still debated. The presence of BM micrometastasis was evaluated in bilateral BM biopsies obtained at diagnosis of 33 patients with stage II/IIIA breast cancer using: (i) a ‘nested’ reverse transcriptase-polymerase chain reaction (RT-PCR) assay for cytokeratin 19 (K19) mRNA, (ii) histology, and (iii) immunohistochemistry (IHC) analysis with a panel of three monoclonal antibodies. The RT-PCR assay only was used to determine contamination of PBSC collections obtained after priming with recombinant human granulocyte-colony stimulating factor (rhG-CSF). K19 transcripts in one or both BM samples were detected in 48% of patients at diagnosis, with an overall 85% concordance with the results of IHC analysis. On the other hand, 56% of PCR- and IHC-positive BM samples were diagnosed as ‘normal’ on histological analysis. 57% of patients showed K19 mRNA in at least one PBSC collection; the possibility to have contaminated PBSC collections was significantly higher in patients with K19 positivity in BM at diagnosis. In four patients who had shown K19 positivity in BM and in PBSC collections, immunoselected CD34+ cells used for haematological rescue were K19-negative. There was a trend towards longer relapse free survival (RFS) in patients transplanted with K19-negative PBSC collections as compared to the others. In conclusion, a substantial proportion of patients with high-risk non-metastatic breast cancer present occult BM micrometastasis at diagnosis and also show cancer contamination of PBSC collections used for AT. These might represent a category of patients with poorer prognosis after AT, and possible... [ABSTRACT FROM AUTHOR]

Objective: Recently autologous haematopoietic stem cell transplantation (AHSCT) has been introduced for the treatment of severe forms of multiple sclerosis (MS). As little data are available on bone marrow (BM) of MS patients undergoing AHSCT, we investigated the morphological and phenotypic characteristics of MS BM. Methods: BM biopsies of 14 MS patients screened for AHSCT and 10 control patients were evaluated to assess cellularity, morphology, immunological profile and bone marrow microenvironment. Immunohistochemistry analysis was performed to evaluate the expression of CD3, CD4, CD8, CD20, CD68, CD45, MMP-9. Results: 8 out of 14 MS (57%) patients showed a reduction of age-related bone marrow cellularity, possibly due to previous immunosuppressive therapies. There were no differences in the T CD3+ lymphocyte expression rate amongst MS and the control patients, the CD4/CD8 ratio (2:1) was maintained as was the rate of B lymphocytes. We found an increased, although not significant, MMP-9 expression (9.2%) in the bone marrow of MS patients, when compared to the control patients (6.3%). Conclusion: The BM of MS patients showed a reduced cellularity and CD45+ cells content in comparison to the controls. A slightly increased expression of MMP-9 was also shown, possibly confirming an involvement of this compartment in the pathogenesis of the disease. [ABSTRACT FROM AUTHOR]