Generation of induced Pluripotent Stem Cells (UNIBSi008-A, UNIBSi008-B, UNIBSi008-C) from an Ataxia-Telangiectasia (AT) patient carrying a novel homozygous deletion in ATM gene.

Using a Sendai Virus based vector delivering Yamanaka Factors, we generated induced Pluripotent Stem Cells (iPSCs) from peripheral blood mononuclear cells of a patient affected by Ataxia Telangiectasia (AT), caused by a novel homozygous deletion in ATM, spanning exons 5-7. Three clones were fully characterized for pluripotency and capability to differentiate. These clones preserved the causative mutation of parental cells and genomic stability over time (>100 passages). Furthermore, in AT derived iPSCs we confirmed the impaired DNA damage response after ionizing radiation. All these data underline potential usefulness of our clones as in vitro AT disease model.

Potential neoplastic evolution of Vero cells: in vivo and in vitro characterization.

Vero cell lines are extensively employed in viral vaccine manufacturing. Similarly to all established cells, mutations can occur during Vero cells in vitro amplification which can result in adverse features compromising their biological safety. To evaluate the potential neoplastic evolution of these cells, in vitro transformation test, gene expression analysis and karyotyping were compared among low- (127 and 139 passages) and high-passage (passage 194) cell lines, as well as transformed colonies (TCs). In vivo tumorigenicity was also tested to confirm preliminary in vitro data obtained for low passage lines and TCs. Moreover, Vero cells cultivated in foetal bovine serum-free medium and derived from TCs were analysed to investigate the influence of cultivation methods on tumorigenic evolution. Low-passage Vero developed TCs in soft agar, without showing any tumorigenic evolution when inoculated in the animal model. Karyotyping showed a hypo-diploid modal chromosome number and rearrangements with no difference among Vero cell line passages and TCs. These abnormalities were reported also in serum-free cultivated Vero. Gene expression revealed that high-passage Vero cells had several under-expressed and a few over-expressed genes compared to low-passage ones. Gene ontology revealed no significant enrichment of pathways related to oncogenic risk. These findings suggest that in vitro high passage, and not culture conditions, induces Vero transformation correlated to karyotype and gene expression alterations. These data, together with previous investigations reporting tumour induction in high-passage Vero cells, suggest the use of low-passage Vero cells or cell lines other than Vero to increase the safety of vaccine manufacturing.

Circulating endothelial cell count: a reliable marker of endothelial damage in patients undergoing hematopoietic stem cell transplantation.

The physio-pathologic interrelationships between endothelium and GvHD have been better elucidated and have led to definition of the entity 'endothelial GvHD' as an essential early phase prior to the clinical presentation of acute GvHD. Using the CellSearch system, we analyzed circulating endothelial cells (CEC) in 90 allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients at the following time-points: T1 (pre-conditioning), T2 (pre-transplant), T3 (engraftment), T4 (onset of GvHD) and T5 (1 week after steroid treatment). Although CEC changes in allo-HSCT represent a dynamic phenomenon influenced by many variables (that is, conditioning, immunosuppressive treatments, engraftment syndrome and infections), we showed that CEC peaks were constantly seen at onset of acute GvHD and invariably returned to pre-transplant values after treatment response. Since we showed that CEC changes during allo-HSCT has rapid kinetics that may be easily missed if blood samples are drawn at pre-fixed time-points, we rather suggest an 'on demand' evaluation of CEC counts right at onset of GvHD clinical symptoms to possibly help differentiate GvHD from other non-endothelial complications. We confirm that CEC changes are a suitable biomarker to monitor endothelial damage in patients undergoing allo-transplantation and hold the potential to become a useful tool to support GvHD diagnosis (ClinicalTrials.gov NCT02064972).

Differential sensitivity of adherent CFU-blast, CFU-mix, BFU-E, and CFU-GM to mafosfamide: implications for adjusted dose purging in autologous bone marrow transplantation.

The availability of an in vitro assay able to detect hematopoietic progenitor cells closely related to those responsible for marrow engraftment following autologous bone marrow transplantation (ABMT) prompted us to establish a procedure aimed at maximally increasing the concentration of the cyclophosphamide derivative mafosfamide used for marrow purging. It, therefore, was the aim of the present study to investigate in a group of patients with acute nonlymphoblastic leukemia (ANLL; n = 19) and acute lymphoblastic leukemia (ALL; n = 19) in complete remission the effect of mafosfamide at the level of adherent blast colony-forming units (blast colony-forming units, CFU-Blast), as well as multipotential (granulocyte erythrocyte macrophage megakaryocyte colony-forming units, CFU-GEMM), erythroid (erythroid burst-forming units, BFU-E), and granulocyte-macrophage (granulocyte-macrophage colony-forming units, CFU-GM) progenitor cells. When nonadherent marrow mononuclear cells (MNCs) were incubated (30 min, 37 degrees C) with increasing doses of mafosfamide (30-120 micrograms/ml), a statistically significant (p less than or equal to 0.0005) dose-dependent suppression of CFU-Blast growth was observed. The mean (+/- 1 standard error of the mean [SEM]) values of 50% inhibition (ID50) of the CFU-Blast growth were not significantly different for ANLL (106 +/- 5) and ALL (107 +/- 5) patients. Analysis of CFU-Blast ID50 distribution demonstrated that ID50 ranged from 100 to 120 micrograms/ml in 17 cases (45%), whereas it ranged from 60 to 100 micrograms/ml in 12 cases and from 120 to 160 micrograms/ml in 9 cases. A statistically significant (p less than or equal to 0.05), dose-dependent suppression of colony growth from multi-potential and lineage-restricted progenitor cells was also observed. However, the value of CFU-Blast ID50 was significantly higher (p less than or equal to 0.05) than CFU-GEMM, BFU-E, and CFU-GM ID50 and ID95 values. In conclusion, our data demonstrate that: 1) the CFU-Blast assay allows to detect on an individual basis the doses of mafosfamide used for marrow purging, and 2) the concentrations of mafosfamide extrapolated by using the CFU-Blast assay are significantly higher than those obtained with the CFU-GM assay. The absence of any detrimental effect on marrow engraftment in vivo supports the safety of the CFU-Blast assay to evaluate the dose of mafosfamide used for marrow purging before ABMT.

In vitro marrow purging in chronic myelogenous leukemia: effect of mafosfamide and recombinant granulocyte--macrophage colony-stimulating factor.

Clinical and experimental evidence revealing Ph1-negative hematopoietic stem cells in the majority of chronic myelogenous leukemia (CML) patients, suggests that autologous bone marrow transplantation (ABMT) may represent a therapeutic approach for these patients. It was the aim of the present study to evaluate the efficacy of the cyclophosphamide derivative mafosfamide as a marrow purging agent in a group (n = 15) of CML patients. Chemical purging was followed by a short-term liquid culture phase supplemented with recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF). Mafosfamide (100 micrograms/ml) incubation induced a marked inhibition of progenitor cell growth, the percentages of surviving CFU-GEMM, BFU-E, and CFU-GM being 3.4, 5.4, and 4.9, respectively. At the cytogenetic level, the purging procedure failed to show any modulating effect on Ph1-negative clones in 9/15 cases. In contrast, 6/15 cases showed a significant increase in the mean (+/- SD) percentage of Ph1-negative metaphases in response to rGM-CSF (46 +/- 26, p less than or equal to 0.05), mafosfamide incubation (53 +/- 12, p less than or equal to 0.01), and the combination of mafosfamide incubation plus rGM-CSF (63 +/- 29, p less than or equal to 0.025). Immunological analysis revealed that mafosfamide incubation induced a significant enrichment of MY10 (28 +/- 9, 0.05) B73.1-positve cells (25 +/- 9, p less than or equal to 0.05). Four mafosfamide-responsive patients with CML in second chronic phase have been autografted with mafosfamide purged marrow. In all patients a Ph1-negative phase lasting 5-14 months was observed. In conclusion, it appears that (a) in a subgroup of CML patients mafosfamide purging is effective in reducing the size of the malignant clone and might induce through its cytotoxic and immune actions a modification of the balance between leukemic and normal clones, and (b) this experimental approach may be used as a screening test to select patients to undergo marrow harvest and ABMT with mafosfamide purged marrow.

Fractionation of chronic myelogenous leukemia marrow cells by stroma adherence: implications for marrow purging.

Chronic myelogenous leukemia (CML) progenitor cells have been shown to be defective in their ability to adhere to marrow stroma. It was the aim of the present study to investigate at the cytogenetic level marrow-derived CML clonogenic cells fractionated on the basis of their ability to adhere to preformed, allogeneic, normal marrow-derived stromal layers. Mononuclear marrow cells from CML patients (n = 15) were incubated with mafosfamide (100 micrograms/ml) or control medium, seeded onto marrow stromal layers and allowed to adhere (3 hrs, 37 degrees C). Following a short-term liquid culture, the different cell fractions were harvested and incorporated in methylcellulose cultures. CFU-GM grown from these cultures were analyzed by single colony karyotyping. On direct cytogenetic analysis, the overall mean (+/- SD) percentage of Ph-negative metaphases was 7 +/- 20%. Following stroma adherence and shortterm suspension culture, the mean (+/- SD) percentages of Ph-negative clones were as follows: 33 +/- 25% for adherent CFU-GM, 59 +/- 40% for adherent, mafosfamide-treated CFU-GM, 12 +/- 16% for non-adherent CFU-GM, and 32 +/- 26% for non-adherent-mafosfamide-treated CFU-GM. If only the patients showing a percentage of Ph-negative clones > or = 20% were included in this analysis, the mean (+/- SD) percentages of Ph-negative clones were 47 +/- 19% for adherent CFU-GM, and 81 +/- 21% for adherent-Mafosfamide-treated CFU-GM. In contrast, the majority of pH-positive CFU-GM were detected within the stroma non-adherent cell fraction.(ABSTRACT TRUNCATED AT 250 WORDS)

[Male sterility and reciprocal translocation (4;15). Description of a case]. / Sterilità maschile e traslocazione reciproca t (4;15). Descrizione di un caso.

Chromosome abnormalities in infertile males are not infrequent, ranging from 4% to about 1% for sex and autosomal chromosomes respectively. Autosomal abnormalities mainly consist of balanced translocations, mostly robertsonian. The Authors report a case of reciprocal translocation t (4;15) associated with oligozoospermia and sterility in a 37 years-old man. The break-points involved in the translocation (4q25; 15p11) seem to be quite uncommon. The possible relationship between this unusual translocation and sterility is discussed.

Molecular and cytogenetic characterization of extra-structurally abnormal chromosomes (ESACs) found prenatally: outcome and follow-up.

A 40-year-old woman underwent amniocentesis at 15.3 weeks of gestation. Chromosome analysis performed using QFQ, DA-DAPI and CBG banding revealed two de novo extra-chromosomal markers (ESACs) in 11 of the 16 colonies analysed. Fluorescence in situ hybridization (FISH) showed that both chromosomes came from the Yq11.22.1 region of the Y chromosome. PCR analysis of genes and STS localized on the Y chromosome excluded the Yp presence specifically of the SRY gene, and most of the euchromatic region of Yq. After extensive genetic counselling and considering both laboratory and second-level ultrasound data, the couple decided to continue the pregnancy. At 37.4 weeks of gestational age, a girl weighing 2750 g was born with an Apgar score of 9/10. A blood sample taken from the umbilical cord showed three cellular lines: mos47,XX, +mar1 ish.der (Y)(wcpY+) [21%]/48,XX, +mar1 ish.der (Y)(wcpY+), +mar2 ish.der (Y)(wcpY+) [41%]/46,XX [38%]. One year after birth, the baby was developing normally and had normal psychomotorial activity.

Identification of Philadelphia-negative granulocyte-macrophage colony-forming units generated by stroma-adherent cells from chronic myelogenous leukemia patients.

Chronic myelogenous leukemia (CML) is a clonal disorder of the hematopoietic stem cell characterized by the coexistence of Philadelphia-negative (Ph-) with Ph+ progenitors. CML progenitor cells have been shown to be defective in adherence to marrow stroma. The present study investigated at the cytogenetic level marrow-derived CML clonogenic cells generated from the stroma-adherent cell fraction. On direct cytogenetic analysis, the overall mean (+/- SEM) percentage of Ph- metaphases was 3% +/- 1%. Mononuclear marrow cells from CML patients (n = 18) were incubated with mafosfamide (100 micrograms/mL) or control medium, seeded onto marrow stromal layers and allowed to adhere (2 hours, 37 degrees C). After a short-term (3-day) liquid culture, the cells were harvested, incorporated in methyl-cellulose, and individual colonies were analyzed by single colony karyotyping. The mean (+/- SEM) percentage of Ph- colonies generated from the stroma-adherent fraction was 35% +/- 6%. As compared with marrow colony-forming unit granulocyte-macrophage plated before any manipulation, the mean (+/- SEM) percentage of Ph- clones was significantly increased by stroma adherence (35% +/- 6% v 15% +/- 4%, P < or = .005) and mafosfamide (100 micrograms/mL) incubation of marrow cells before stroma adherence (58% +/- 9% v 35% +/- 6%, P < or = .005). An additive effect was observed by combining mafosfamide treatment and stroma adherence. Single-colony transfer experiments showed that 50% +/- 4% stroma-adherent and 70% +/- 4% stroma-adherent mafosfamide-treated progenitors gave rise to secondary colonies. To further characterize the stroma-adherent fraction, experiments were performed in which CD34+ marrow cells were used. The mean (+/- SEM) output of progenitors generated by 10,000 CD34+, stroma-adherent cells was 888 +/- 188 and 570 +/- 258 for untreated and mafosfamide-treated cells, respectively. Individual colonies were analyzed by single-colony karyotyping and fluorescent in situ hybridization using a biotinylated cosmid DNA probe that hybridize to abl oncogene. The CD34+, stroma-adherent fraction contained 38% +/- 14% (untreated) and 56% +/- 18% (mafosfamide-treated) (P < or = .025) Ph- progenitors. In conclusion, the present data show the possibility to select Ph- clones that (1) have a maintained capability of stroma adherence, (2) are mafosfamide resistant, (3) are derived from the CD34+ fraction, and (4) have high-replating potential.

Biological and chemical selection of Ph-negative clones.

Chronic myelogenous leukemia (CML) is a clonal disorder of the hematopoietic stem cell characterized by the co-existence of Philadelphia-negative with Ph-positive progenitors. CML progenitor cells have been shown to be defective in adherence to marrow stroma. The present study investigated at the cytogenetic level marrow-derived CML clonogenic cells generated from the stroma-adherent cell fraction. Mononuclear marrow cells from CML patients (n = 20) were incubated with mafosfamide (100 micrograms/ml) or control medium, seeded onto marrow stromal layers, and allowed to adhere (2 h, 37 degrees C). Following a short-term (3 days) liquid culture, the cells were harvested, incorporated in methylcellulose, and individual colonies were analyzed by single colony karyotyping. On direct cytogenetic analysis, the overall mean (+/- SD) percentage of Ph-negative metaphases was 9 +/- 20%. The mean (+/- SD) percentages of Ph-negative colonies grown from the stroma-adherent and the stroma-adherent mafosfamide-treated fraction were 41 +/- 32% and 62 +/- 40% (p < or = .005), respectively. Single colony transfer experiments revealed that 50 +/- 13% stroma-adherent and 70 +/- 24% stroma-adherent mafosfamide-treated progenitors gave rise to secondary colonies. In conclusion, the present data demonstrate the possibility to select Ph-negative clones that: 1) have a maintained capability of stroma adherence; 2) are mafosfamide resistant; and 3) have high-replating potential.