Robert Dębski

Intrathecal therapy with rituximab in central nervous system involvement of post-transplant lymphoproliferative disorder

Abstract Post-transplant lymphoproliferative disorder (PTLD) caused by Epstein–Barr virus (EBV) is a severe complication in high-risk allogeneic hematopoietic stem cell transplant (HSCT) recipients. Central nervous system (CNS) involvement of PTLD is a very rare event in patients with HSCT. As no established standard therapy in CNS-EBV-PTLD is available, the aim of this study was analysis of the safety and efficacy of intrathecal rituximab therapy in a group of eight children and adolescents with CNS-EBV-PTLD. Seven patients responded to therapy: all clinical symptoms and EBV-DNA viral load resolved after a median 2 (range: 1–7) doses of rituximab. However, some magnetic resonance imaging (MRI) changes in brain scan persisted in two patients. In all patients, except one, no adverse events of the therapy were observed. In conclusion, intrathecal rituximab administration seems to be an effective and safe method of treatment of CNS-EBV-PTLD in pediatric stem cell recipients. We recommend this treatment modality for further investigation.

Is the Poly (L- Lactide- Co– Caprolactone) Nanofibrous Membrane Suitable for Urinary Bladder Regeneration?

The purpose of this study was to compare: a new five-layered poly (L–lactide–co–caprolactone) (PLC) membrane and small intestinal submucosa (SIS) as a control in rat urinary bladder wall regeneration. The five-layered poly (L–lactide–co–caprolactone) membrane was prepared by an electrospinning process. Adipose tissue was harvested from five 8-week old male Wistar rats. Adipose derived stem cells (ADSCs) were seeded in a density of 3×106 cells/cm2 onto PLC membrane and SIS scaffolds, and cultured for 5-7 days in the stem cell culture medium. Twenty male Wistar rats were randomly divided into five equal groups. Augmentation cystoplasty was performed in a previously created dome defect. Groups: (I) PLC+ 3×106ADSCs; (II) SIS+ 3×106ADSCs; (III) PLC; (IV) SIS; (V) control. Cystography was performed after three months. The reconstructed urinary bladders were evaluated in H&E and Massons trichrome staining. Regeneration of all components of the normal urinary bladder wall was observed in bladders augmented with cell-seeded SIS matrices. The urinary bladders augmented with SIS matrices without cells showed fibrosis and graft contraction. Bladder augmentation with the PLC membrane led to numerous undesirable events including: bladder wall perforation, fistula or diverticula formation, and incorporation of the reconstructed wall into the bladder lumen. The new five-layered poly (L–lactide–co–caprolactone) membrane possesses poorer potential for regenerating the urinary bladder wall compared with SIS scaffold.

Hematopoietic stem cell transplant in patients with activated PI3K delta syndrome.

Zohreh Nademi, PhD, Mary A. Slatter, MD, Christopher C. Dvorak, MD, Benedicte Neven, MD, Alain Fischer, MD, Felipe Suarez, MD, Claire Booth, MD, Kanchan Rao, MD, Alexandra Laberko, MD, Julia Rodina, MD, Yves Bertrand, MD, Sylwia Kołtan, MD, Robert Dębski, MD, Terence Flood, MD, Mario Abinun, MD, Andrew R. Gennery, MD, Sophie Hambleton, DPhil, Stephan Ehl, MD, Andrew J. Cant, MD, on behalf of the Inborn Errors Working Party of EBMT and ESID

Hair follicle stem cells can be driven into a urothelial-like phenotype: an experimental study.

The aim of this study was to show that conditioned medium might induce transdifferentiation of hair follicle stem cells into urothelial‐like cells. Several conditioned media and culture conditions (skeletal muscle cell conditioned medium, smooth muscle cell conditioned medium, fibroblast conditioned medium, transforming growth factor‐conditioned medium, urothelial cell conditioned medium, and co‐culture of hair follicle stem cells and urothelial cells) were used. The hair follicle stem cells phenotype from rat whisker hair follicles was checked by using flow cytometry and immunofluorescence. Cytokeratins 7, 8, 15 and 18 were used as markers. Urothelial cell conditioned medium increased the expression of urothelial markers (cytokeratin 7, cytokeratin 8, cytokeratin 18), whereas it decreased a hair follicle stem cells marker (cytokeratin 15) after 2 weeks of culture. This process depended on the time of cultivation. This medium was able to sustain the epithelial phenotype of the culture. Other media including a co‐culture system failed to induce similar changes. Smooth muscle conditioned medium resulted in a loss of cells in culture. Hair follicle stem cells are capable of differentiating into urothelial‐like cells in vitro when exposed to a bladder‐specific microenvironment.

Ciprofloxacin is a potential topoisomerase II inhibitor for the treatment of NSCLC.

Lung cancer is one of the most common tumors and its treatment is still inefficient. In our previous work we proved that ciprofloxacin has a different influence on five cancer cell lines. Here, we aimed to compare the biological effect of ciprofloxacin on cell lines representing different responses after treatment, thus A549 was chosen as a sensitive model, C6 and B16 as highly resistant. Three different cell lines were analyzed (A549, B16 and C6). The characterization of continuous cell growth was analyzed with the Real-Time Cell Analyzer (RTCA)-DP system. Cytoskeletal changes were demonstrated using immunofluorescence. The cell cycle was analyzed using flow cytometry. Ciprofloxacin was cytostatic only against the A549 cell line. In the case of other tested cell lines a cytostatic effect was not observed. Cytoskeletal analysis confirms the results obtained with RTCA-DP. A549 cells were inhibited in the G2/M phase suggesting a mechanism related to topoisomerase II inhibition. The biological effects of ciprofloxacin support the hypothesis that this drug can serve as an adjuvant treatment for lung cancer, due to its properties enabling topoisomerase II inhibition.

The application of conventional cytogenetics, FISH, and RT-PCR to detect genetic changes in 70 children with ALL

We investigated bone marrow cells of 70 acute lymphoblastic leukemia children by conventional cytogenetics (CC), fluorescence in situ hybridization (FISH), and reverse transcription polymerase chain reaction (RT-PCR) methods. CC and RT-PCR for fusion genes BCR/ABL, MLL/AF4, E2A/PBX1, TEL/AML1 were performed at diagnosis in each patient. FISH was performed to verify the presence of fusion genes and MLL rearrangements and to estimate the percentage of abnormal cells. Karyotypes were obtained in 59 (84%) of 70 cases. Thirty-five (59%) of 59 cases revealed chromosome aberrations. Hyperdiploidy >50 chromosomes was present in nine cases, hyperdiploidy 47–50 chromosomes in six, pseudodiploidy in 15, and hypodiploidy in five. BCR/ABL was present in two cases, PBX1/E2A in two, and TEL/AML1 in 14. MLL/AF4 was not found, but the rearrangements of MLL gene were present in five children. The addition of RT-PCR and FISH to CC was of the utmost importance. One of two Ph translocations and one of two t(1;19) were first revealed by RT-PCR. Moreover, FISH showed the percentage of TEL/AML1(+) cells that turned to be an important prognostic factor. The outcome was the best for the children with hyperdiploidy >50 chromosomes without structural changes. It was also good for those with TEL/AML1 present in ≥80% of cells without chromosome aberrations. The presence of pseudodiploidy correlated with poor outcome. The outcome for patients with t(9;22)–BCR/ABL or 11q23–MLL rearrangement was the worst in study group. The presence of BCR/ABL caused eight times increase of risk of death; MLL rearrangements caused 12 times increase.

Ex vivo drug resistance profile in childhood acute myelogenous leukemia: no drug is more effective in comparison to acute lymphoblastic leukemia.

Therapy results in childhood acute myelogenous leukemia (AML) differ from those of acute lymphoblastic leukemia (ALL). Cellular drug resistance might be one of the reasons of therapy failure in AML. The aim of the study was the analysis of ex vivo drug resistance profile in childhood initial and relapsed AML in comparison to initial ALL. Fifty-three AML samples were tested for chemosensitivity and results were compared with those of 106 initial ALL samples. Ex vivo drug resistance was tested by means of the MTT assay. Up to 29 cytotoxic drugs were tested for each patient. When compared to de novo ALL samples, myeloblasts from initial AML samples were significantly more resistant to most tested drugs, except cytarabine, mercaptopurine and thioguanine. Relapsed AML samples, in relation to initial AML samples, showed comparable sensitivity to cytarabine, idarubicin, fludarabine and cladribine. Patients, who have died due to refractory or relapsing disease, were already on first diagnosis 2-fold more resistant to cytarabine, 6.4-fold more resistant to cisplatin and 3-fold more resistant to carboplatin, when compared to those who stay in remission. Resistance to prednisolone was observed in 85% initial and all relapsed AML samples, in comparison to 33% of ALL samples. Resistance to cytarabine occurred in 2.1% of ALL and 12% of AML cases while a patient with Down syndrome presented the most sensitive drug resistance profile. In conclusion this study shows that no drug was found which, on average, was more effective in AML than in ALL samples. The sensitivity of myeloblasts to platinum derivatives might have prognostic value.

Does mobilisation of CD34+ stem cells along with VEGF, angiogenin, IL-6, IL-8, and hsCRP levels allow predicting the direction of left ventricular ejection fraction and wall motion score index changes in patients with myocardial infarction?

BACKGROUND Left ventricular (LV) systolic function is a significant prognostic factor in patients after myocardial infarction (MI). Multiple angiogenic and inflammatory factors are involved in postinfarction LV remodelling process. In addition, CD34+progenitor cells mobilised from bone marrow and tissue niches participate in regeneration of the infarcted myocardium. AIM To examine relationships between LV ejection fraction (LVEF) and wall motion score index (WMSI) and the number of CD34+ cells and plasma levels of vascular endothelial growth factor (VEGF), angiogenin and such inflammatory factors as interleukin 6 (IL-6), interleukin 8 (IL-8), and high-sensitivity C-reactive protein (hsCRP) in patients with ST-elevation MI (STEMI). METHODS The study group included 61 patients with STEMI treated with primary percutaneous coronary intervention (PCI)involving bare metal stent implantation. Plasma levels of the evaluated angiogenic and inflammatory factors were measured by flow cytometry at 4 time points (just before PCI, 24 h later, at hospital discharge, and 30 days after STEMI). LVEF and WMSI were measured by echocardiography at hospital discharge, 1 month later, and 6 months later. We compared angiogenic and inflammatory factor levels in patients with no improvement of the LV systolic function during the follow-up (group 1, n = 22)vs. those with improved LV systolic function (group 2, n = 39). RESULTS No differences in the levels of VEGF, angiogenin, IL-6, IL-8, and hsCRP, and the number of CD34+ cells were observed between the two groups. Despite this, we found significant negative correlations between hsCRP level and LVEF,and positive correlations between hsCRP level and WMSI in both patient groups, but these correlations were much stronger in group 1. We also found a significant negative correlation between WMSI at 6 months and the number of CD34+ cells measured 24 h after PCI. CONCLUSIONS 1. Evaluation of plasma VEGF, angiogenin, IL-6, IL-8, and hsCRP levels and the number of CD34+ cells at different time points in patients with STEMI did not allow predicting the direction of changes in LVEF and WMSI. 2. Observed significant correlations between hsCRP level and LVEF and WMSI may suggest a harmful effect of inflammation on postinfarction myocardial remodelling. 3. A significant negative correlation between the number of CD34+ and WMSI suggests that increased mobilisation of these cells might have a beneficial effect on systolic function after MI.

Does the Harvesting Technique Affect the Properties of Adipose-Derived Stem Cells? - The Comparative Biological Characterization.

The objective of this study was to evaluate complex biological properties of human stem cells isolated from adipose tissue (ASCs) harvested utilizing different methods: surgical resection (R), power‐assisted liposuction (PAL), and laser‐assisted liposuction (LAL). ASCs were isolated from healthy donors, due to surgical resection, power‐, and laser‐assisted liposuction. Isolated cells were characterized by their clonogenicity, proliferation rate, doubling time, multilineage differentiation, and senescence potential. The average number of ASCs from 1g/1 ml of solid adipose tissue/lipoaspirate was 2.9 × 105 ± 2.4 × 105, 1.1 × 105 ± 0.8 × 105, and 1.2 × 105 ± 0.7 × 105, respectively, for ASCsR, ASCsPAL, and ASCsLAL. However, number of colonies formed by ASCsR and ASCsPAL was significantly higher compared to the average number of colonies formed by ASCsLAL. Also, in comparison to other analyzed cell groups, ASCsPAL obtained the highest proliferative activity. All analyzed cells were characterized by stable expression of CD90 and CD44 markers during prolonged culture. Expression of CD34 and CD45 markers was decreasing in subsequent passages. Presented study shows that different ASCs collection method affects some basic characteristics of these cells, such as number of isolated cells, clonogeneity, or doubling time. J. Cell. Biochem. 118: 1097–1107, 2017.

Prostate epithelial stem cells are resistant to apoptosis after α1-antagonist treatment. The impact for BPH patients.

Introduction Induction of apoptosis in prostatic epithelial cells by doxazosin, terazosin and prazosin has been well documented. However, the biochemical pathways of doxazosin action is still unclear. Aforementioned drugs should lead to decrease of prostate volume, although this effect was never observed in patients suffering from BPH after treatment with α1-antagonists. Probably, it is connected with cancer stem cells’ resistance on chemotherapeutic agents. The aim of this study was to compare incidence of apoptosis induced by doxazosin in progenitor and differentiated cells isolated from human prostate epithelium. Material and methods For this purpose tissue specimens were obtained from 10 patients suffering from BPH, the primary cultures of prostate epithelium were established and CD133 MicroBeads sorting was prepared. Both, CD133(+)/CD133(-) co-cultures and CD133(+) cells were incubated with different concentration of doxazosin for 12 h. Cell viability and apoptosis was estimated with Annexin V-FITC. Results 12 h incubation of CD133(+)/CD133(-) co-cultures with doxazosin resulted in increase of apoptotic cells, while in CD133(+) cultures no changes were observed. Correlation between apoptotic cell number and doxazosin concentration in CD133(+)/ CD133(-) co-cultures group was high (R = 0.99). Conclusion Doxazosin induced apoptosis in co-cultures of progenitor and differentiated epithelial cells. However, progenitor cells were not susceptible to apoptosis, what can be a reason of treatment failure in BPH patients.