Production via good manufacturing practice of exofucosylated human mesenchymal stromal cells for clinical applications.

BACKGROUND: The regenerative and immunomodulatory properties of human mesenchymal stromal cells (hMSCs) have raised great hope for their use in cell therapy. However, when intravenously infused, hMSCs fail to reach sites of tissue injury. Fucose addition in α(1,3)-linkage to terminal sialyllactosamines on CD44 creates the molecule known as hematopoietic cell E-/L-selectin ligand (HCELL), programming hMSC binding to E-selectin that is expressed on microvascular endothelial cells of bone marrow (BM), skin and at all sites of inflammation. Here we describe how this modification on BM-derived hMSCs (BM-hMSCs) can be adapted to good manufacturing practice (GMP) standards. METHODS: BM-hMSCs were expanded using xenogenic-free media and exofucosylated using α(1,3)-fucosyltransferases VI (FTVI) or VII (FTVII). Enforced fucosylation converted CD44 into HCELL, and HCELL formation was assessed using Western blot, flow cytometry and cell-binding assays. Untreated (unfucosylated), buffer-treated and exofucosylated BM-hMSCs were each analyzed for cell viability, immunophenotype and differentiation potential, and E-selectin binding stability was assessed at room temperature, at 4°C, and after cryopreservation. Cell product safety was evaluated using microbiological testing, karyotype analysis, and c-Myc messenger RNA (mRNA) expression, and potential effects on genetic reprogramming and in cell signaling were analyzed using gene expression microarrays and receptor tyrosine kinase (RTK) phosphorylation arrays. RESULTS: Our protocol efficiently generates HCELL on clinical-scale batches of BM-hMSCs. Exofucosylation yields stable HCELL expression for 48 h at 4°C, with retained expression after cell cryopreservation. Cell viability and identity are unaffected by exofucosylation, without changes in gene expression or RTK phosphorylation. DISCUSSION: The described exofucosylation protocol using xenogenic-free reagents enforces HCELL expression on hMSCs endowing potent E-selectin binding without affecting cell viability or native phenotype. This described protocol is readily scalable for GMP-compliant clinical production.

Characterization of chromosome 14 abnormalities by interphase in situ hybridization and comparative genomic hybridization in 124 meningiomas: correlation with clinical, histopathologic, and prognostic features.

We analyzed quantitative chromosome 14 abnormalities in 124 meningiomas by interphase fluorescence in situ hybridization (iFISH) and confirmed the nature of abnormalities by comparative genomic hybridization (CGH). We correlated the abnormalities with clinical, histopathologic, and prognostic factors. Of 124 cases, 50 (40.3%) showed loss (14.5%) or gain (25.8%) of the 14q32 chromosome region by iFISH. Most corresponded to numeric abnormalities: monosomy (12.9%), trisomy (1.6%), or tetrasomy (24.2%); in only 2 cases (1.6%), chromosome 14 loss did not involve the whole chromosome and was restricted to the 14q31-q32 region (confirmed by CGH). Cases with gain or monosomy corresponded more frequently to histologically malignant tumors (P = .009). Patients with monosomy 14/14q-, but not those with gain, more often were male (P = .04) and had a greater incidence of recurrence (P = .003) and shorter relapse-free survival (P = .03). The 2 patients with loss limited to 14q31-q32 had histologically benign tumors and no relapse after more than 5 years' follow-up. Most meningiomas with chromosome 14 abnormalities have numeric changes, with interstitial deletions of 14q31-q32 present in few cases. Of the abnormalities detected, only monosomy 14 showed an adverse prognostic impact.

Cytoprotective effects of melatonin on zoledronic acid-treated human mesenchymal stem cells in vitro.

OBJECTIVE: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a common clinical complication in patients receiving bisphosphonate therapy. Furthermore, melatonin has been proposed as a therapeutic drug for the oral cavity due to its antioxidant properties. This study aimed to evaluate the cytoprotective effects of melatonin on zoledronic acid (ZA)-treated human mesenchymal stem cells from periodontal ligament (PDLSCs) and bone marrow (BMMSCs). METHODS: PDLSCs and BMMSCs were exposed to ZA, melatonin or ZA + melatonin for 72 h. Cell proliferation was measured by a colorimetric assay, whereas their mesenchymal phenotype was analyzed by flow cytometry. RESULTS: Proliferation assays showed that BMMSCs presented higher ZA resistance than PDLSCs, as well as a difference in response to the simultaneous treatment of ZA + melatonin. Using PDLSCs, high doses of melatonin significantly increased their proliferation, whereas lower concentrations were enough to enhance ZA-treated BMMSC proliferation. Moreover, PDLSCs displayed a CD90/CD105 downregulation and CD73 upregulation in response to ZA, which was more pronounced in response to melatonin. Furthermore, ZA or ZA + low doses of melatonin induced a decrease of expression of CD90/CD105/CD73 on BMMSCs, while a higher concentration recovered CD73 levels. CONCLUSION: These results suggest that melatonin has a cytoprotective effect on ZA-treated PDLSCs and BMMSCs. Thus, it could be used for BRONJ prevention.

Clinicobiological, immunophenotypic, and molecular characteristics of monoclonal CD56-/+dim chronic natural killer cell large granular lymphocytosis.

Indolent natural killer (NK) cell lymphoproliferative disorders include a heterogeneous group of patients in whom persistent expansions of mature, typically CD56(+), NK cells in the absence of any clonal marker are present in the peripheral blood. In the present study we report on the clinical, hematological, immunophenotypic, serological, and molecular features of a series of 26 patients with chronic large granular NK cell lymphocytosis, whose NK cells were either CD56(-) or expressed very low levels of CD56 (CD56(-/+dim) NK cells), in the context of an aberrant activation-related mature phenotype and proved to be monoclonal using the human androgen receptor gene polymerase chain reaction-based assay. As normal CD56(+) NK cells, CD56(-/+dim) NK cells were granzyme B(+), CD3(-), TCRalphabeta/gammadelta(-), CD5(-), CD28(-), CD11a(+bright), CD45RA(+bright), CD122(+), and CD25(-) and they showed variable and heterogeneous expression of both CD8 and CD57. Nevertheless, they displayed several unusual immunophenotypic features. Accordingly, besides being CD56(-/+dim), they were CD11b(-/+dim) (heterogeneous), CD7(-/+dim) (heterogeneous), CD2(+) (homogeneous), CD11c(+bright) (homogeneous), and CD38(-/+dim) (heterogeneous). Moreover, CD56(-/+dim) NK cells heterogeneously expressed HLA-DR. In that concerning the expression of killer receptors, CD56(-/+dim) NK cells showed bright and homogeneous CD94 expression, and dim and heterogeneous reactivity for CD161, whereas CD158a and NKB1 expression was variable. From the functional point of view, CD56(-/+dim) showed a typical Th1 pattern of cytokine production (interferon-gamma(+), tumor necrosis factor-alpha(+)). From the clinical point of view, these patients usually had an indolent clinical course, progression into a massive lymphocytosis with lung infiltration leading to death being observed in only one case. Despite this, they frequently had associated cytopenias as well as neoplastic diseases and/or viral infections. In summary, we describe a unique and homogeneous group of monoclonal chronic large granular NK cell lymphocytosis with an aberrant activation-related CD56(-/+dim)/CD11b(-/+dim) phenotype and an indolent clinical course, whose main clinical features are related to concomitant diseases.