Danuta Jarocha

Adventage of mesenchymal stem cells (MSC) expansion directly from purified bone marrow CD105+ and CD271+ cells.

UNLABELLED Mesenchymal Stem Cells (MSC) are employed in gene and cellular therapies. Routinely MSC are isolated from bone marrow mononuclear cells (MNC) by plastic adherence. Here we compared new isolation strategies of bone marrow MSC including immunodepletion of hematopoietic cells and immunomagnetic isolation of CD105+ and CD271+ populations. Four fractions were obtained: MNC MSC, RosetteSep-isolated MSC, CD105+ and CD271+ sorted MSC. We evaluated i) number of CFU-F colonies, ii) cell phenotype, iii) in vitro differentiation of expanded cells and iv) expression of osteo/adipogenesis related genes. RESULTS Average number of day 9 CFU-F colonies was the highest for CD271 positive fraction. Real-Time PCR analysis revealed expression of RUNX2, PPARgamma and N-cadherin in isolated cells, particularly high in CD271+ cells. Expression of CD105, CD166, CD44, CD73 antigens was comparable for all expanded populations (over 90%). We observed various levels of hematopoietic contamination with the highest numbers of CD45+ cells in MNC-MSC fraction and the lowest in CD105+ and CD271+ fractions. Cells of all the fractions were CD34 antigen negative. Expanded CD105 and CD271 populations showed higher level of RUNX2, osteocalcin, PTHR, leptin, PPARgamma2 and aggrecan1 genes except for alpha1 collagen. After osteogenic differentiation CD105+ and CD271+ populations showed lower expression of RUNX, PPARgamma2 and also lower expression of osteocalcin and PTHR than MNC, with comparable alpha1-collagen expression. Chondrogenic and adipogenic gene expression was higher in MNC. More clonogenic CD105+ and particularly CD271+ cells, which seem to be the most homogenous fractions based on Real-Time PCR and immunostaining data, are better suited for MSC expansion.

Genetically modified adipose tissue−derived mesenchymal stem cells overexpressing CXCR4 display increased motility, invasiveness, and homing to bone marrow of NOD/SCID mice

OBJECTIVE This study evaluates usefulness of CXCR4 overexpression via retroviral transduction in adipose tissue-derived mesenchymal stem cells (AT-MSCs) as a strategy to increase their migration and engraftment ability. MATERIALS AND METHODS AT-MSCs were isolated from lipoaspirates from human healthy donors with liberase 3. Cells were transduced with retroviral vector carrying either CXCR4 or green fluorescent protein (GFP) complementary DNA, and neo-resistant colonies were selected and used in experiments. Chemotaxis, invasion through Matrigel, motor activity, gene expression, osteodifferentiation potential, and engraftment into bone marrow of nonobese diabetic/severe combined immunodeficient mice were analyzed for CXCR4-overexpressing cells and GFP-control cells. RESULTS Approximately 90% of retrovirus-transduced AT-MSCs expressed CXCR4 or GFP and maintained their ability to differentiate into osteocytes. CXCR4-transduced AT-MSCs displayed enhanced migration and higher invasiveness toward SDF-1 gradient. The upregulation of CXCR4 led to phosphorylation of mitogen-activated protein and AKT kinases and an increase in metalloproteinase expression after SDF-1 stimulation. The transplantation of CXCR4-transduced AT-MSCs into nonobese diabetic/severe combined immunodeficient mice led to increased engraftment into bone marrow in comparison to GFP-transduced AT-MSCs. CONCLUSIONS Adipose tissue is one of the alternative sources of MSCs to bone marrow. We showed that AT-MSCs overexpressing CXCR4 preserve their ability for osteodifferentiation. Enhanced migration and engraftment of the transduced AT-MSCs into bone marrow indicate the usefulness of this strategy in overcoming low engraftment of MSCs in clinical approaches of cellular therapies for bone disorders and can represent a powerful tool in regenerative medicine and gene therapies. Thus, these cells may be used as an alternative to bone marrow-derived MSCs.

Autologous muscle-derived cells for the treatment of female stress urinary incontinence: A 2-year follow-up of a polish investigation

We evaluated the safety, feasibility and initial effects of therapy with muscle‐derived cells (MDCs) for women with stress urinary incontinence (SUI).

Continuous Improvement after Multiple Mesenchymal Stem Cell Transplantations in a Patient with Complete Spinal Cord Injury

Interruption of spinal cord (SC) continuity leads to functional loss below the lesion level. The purpose of this study was to evaluate the safety and efficacy of bone marrow nucleated cell (BMNC) and multiple mesenchymal stem cell (MSC) transplantations in spinal cord injury (SCI). A patient with total SC interruption at the Th2-3 level underwent experimental therapy with BMNC and MSC transplantations followed with intensive neurorehabilitation treatment. At admission, 6 h after SCI, the patient was scored ASIA A, had a Th1 sensation level, paraplegia with sphincter palsy, and was without the ability to control trunk movement. Neurophysiology examination showed bilateral axonal damage to the motor and sensory neural fibers with no motor unit potentials or peripheral motor nerve conduction in the lower extremities. The standard therapy had been applied and had not produced any positive results. The patient was treated with autologous BMNCs injected intravenously (3.2 × 109) and intrathecally (0.5 × 109) 10 weeks after the SCI and with five rounds of MSCs every 3-4 months (1.3-3.65 × 107) administered via lumbar puncture. Total number of transplanted MSC cells during the course of treatment was 1.54 × 108. There were no complications related to transplantations and no side effects related to the therapy during 2 years of treatment. The ASIA score improved from A to C/D (from 112 to 231 points). The sensation level expanded from Th1 to L3-4, and the patients ability to control the body trunk was fully restored. Bladder filling sensation, bladder control, and anal sensation were also restored. Muscle strength in the left lower extremities improved from plegia to deep paresis (1 on the Lovett scale). The patients ability to move lower extremities against gravity supported by the movements in quadriceps was restored. The patient gained the ability to stand in a standing frame and was able to walk with the support of hip and knee ortheses. Magnetic resonance imaging (MRI) revealed that at the Th2/Th3 level, where the hemorrhagic necrosis was initially observed, small tissue structures appeared. Our results suggest that repeated intrathecal infusions of MSCs might have the potential to produce clinically meaningful improvements for SCI patients.

Preliminary Study of Autologous Bone Marrow Nucleated Cells Transplantation in Children With Spinal Cord Injury

The objective of this study was to assess the safety and efficacy of transplanting bone marrow nucleated cells (BMNCs) to treat children with complete interruption of spinal cord (SC) continuity. The present study was conducted from 2005 to 2011. The inclusion criteria were a magnetic resonance imaging‐confirmed complete interruption of SC continuity and no improvement in neurological status within 6 months after standard therapy. Bone marrow was isolated from the iliac ala and submitted to BMNC isolation. Subsequently, the cell suspension was administered into the SC cavity and intravenously. In total, 18 of 19 intraspinal and intravenous BMNC transplantation procedures performed caused no adverse events. One case was connected with transient bradycardia. The experimental therapy showed no late complications in the 1‐ to 6‐year follow‐up evaluation period. Neurological improvement was observed in two patients who received multiple implantations. One patient demonstrated improved superficial sensation from Th3 to Th12/L1 and a restored bladder‐filling sensation. In the other case, superficial sensation was improved from C2 to C5, and the respiratory drive, the swallowing reflex, and tongue movements were restored. Spasticity and quality of life were improved in three of five patients. In addition, skin pressure ulcers healed and did not recur. Our preliminary results demonstrate the safety and feasibility of BMNC transplantation in children with complete SC injury. The results indicate that a certain degree of neurological and quality‐of‐life improvement can be attained by children with chronic complete SC injury who receive multiple BMNC implantations.

Infarct size determines myocardial uptake of CD34+ cells in the peri-infarct zone: results from a study of (99m)Tc-extametazime-labeled cell visualization integrated with cardiac magnetic resonance infarct imaging.

Background— Effective progenitor cell recruitment to the ischemic injury zone is a prerequisite for any potential therapeutic effect. Cell uptake determinants in humans with recent myocardial infarction are not defined. We tested the hypothesis that myocardial uptake of autologous CD34+ cells delivered via an intracoronary route after recent myocardial infarction is related to left ventricular (LV) ejection fraction (LVEF) and infarct size. Methods and Results— Thirty-one subjects (age, 36–69 years; 28 men) with primary percutaneous coronary intervention–treated anterior ST-segment–elevation myocardial infarction and significant myocardial injury (median peak troponin I, 138 ng/mL [limits, 58–356 ng/mL]) and sustained LVEF depression at ⩽45% were recruited. On day 10 (days 7–12), 4.3×106 (0.7–9.9×106) 99mTc-extametazime–labeled autologous bone marrow CD34+ cells (activity, 77 MBq [45.9–86.7 MBq]) were administered transcoronarily (left anterior descending coronary artery). 99mTc-methoxyisobutyl isonitrile (99mTc-MIBI) single-photon emission computed tomography before cell delivery showed 7 (2–11) (of 17) segments with definitely abnormal/absent perfusion. Late gadolinium-enhanced infarct core mass was 21.7 g (4.4–45.9 g), and infarct border zone mass was 29.8 g (3.9–60.2 g) (full-width at half-maximum, signal intensity thresholding algorithm). One hour after administration, 5.2% (1.7%–9.9%) of labeled cell activity localized in the myocardium (whole-body planar &ggr; scan). Image fusion of labeled cell single-photon emission computed tomography with LV perfusion single-photon emission computed tomography or with cardiac magnetic resonance infarct imaging indicated cell uptake in the peri-infarct zone. Myocardial uptake of labeled cells activity correlated in particular with late gadolinium-enhanced infarct border zone mass (r=0.84, P<0.0001); it also correlated with peak TnI (r=0.76, P<0.001), severely-abnormal/absent perfusion segment number (r=0.45, P=0.008), and late gadolinium-enhanced infarct core (r=0.58, P=0.0003) but not with echocardiography LVEF (r=−0.07, P=0.68) or gated single-photon emission computed tomography LVEF (r=−0.28, P=0.16. The correlation with cardiac magnetic resonance imaging-LVEF was weak (r=−0.38; P=0.04). Conclusions— This largest human study with labeled bone marrow CD34+ cell transcoronary transplantation after recent ST-segment–elevation myocardial infarction found that myocardial cell uptake is determined by infarct size rather than LVEF and occurs preferentially in the peri-infarct zone.

Role of I-TAC-binding receptors CXCR3 and CXCR7 in proliferation, activation of intracellular signaling pathways and migration of various tumor cell lines.

Chemokines and its receptors stimulate tumor growth, migration and invasion. In this study we evaluated the expression and function of CXCR3 and CXCR7 receptors in cervical carcinoma, rhabdomyosarcoma and glioblastoma cell lines. We found that both receptors were expressed at different degree by tumor cells. CXCR7 was expressed at both mRNA and protein level by all tumor cell lines. The expression of CXCR7 differed between rhabdomyosarcoma subtypes. The receptor was highly expressed in alveolar rhabdomyosarcoma and the expression was low in embryonal rhabdomyosarcoma. The expression of CXCR3 was low in majority of the tumor cell lines. Upon I-TAC stimulation AKT and MAPK kinases were activated. However, the activation of growth promoting pathways did not increased the proliferation rate of tumor cells. Since chemokines stimulate the migration of various cell types the ability of I-TAC to stimulate migration of tumor cells were studied. We did not observe the migration of tumor cells toward I-TAC gradient alone. However, at the low dose, I-TAC sensitized tumor cells toward SDF-1beta gradient and synergized with SDF-1beta in activation of intracellular pathways. Our data suggest an important role of I-TAC and its receptors in biology of solid tumors and we postulate that I-TAC-binding receptors might be used as the potential targets for antitumor therapy.

The decreased metastatic potential of rhabdomyosarcoma cells obtained through MET receptor downregulation and the induction of differentiation

Rhabdomyosarcoma (RMS) is the most common type of pediatric soft tissue sarcoma. The MET receptor has an important role in the biology of RMS, and its overexpression and hyperactivation correlate with the metastatic ability of RMS. Consequently, interfering with MET expression or functionality may constitute a sound strategy for reducing the progression and metastatic potential of RMS. Our study reveals that downregulation of the MET receptor leads to changes in the morphology of ARMS cell in vivo. Tumors acquire a spindle shape that is characteristic of muscle fibers. Inhibition of MET expression or function leads to (i) a decreased expression of the early myogenic marker MyoD, (ii) a decreased ability of ARMS cells to metastasize to bone marrow cavities, (iii) downregulation of CXCR4 receptor expression and (iv) a decreased migration of MET-depleted cells towards gradients of HGF and SDF-1. Finally, we demonstrate that in vitro differentiation of alveolar RMS cells decreases their metastatic behavior by reducing both the expression of the MET and CXCR4 receptors and their migratory response to HGF and SDF-1. These findings suggest that blockers of MET receptor function and inducers of RMS cells differentiation may be clinically useful for reducing the aggressiveness and metastatic potential of RMS and may have significant implications for its treatment.

Myocardial regeneration strategy using Wharton's jelly mesenchymal stem cells as an off-the-shelf 'unlimited' therapeutic agent: results from the Acute Myocardial Infarction First-in-Man Study.

Introduction In large-animal acute myocardial infarction (AMI) models, Whartons jelly (umbilical cord matrix) mesenchymal stem cells (WJMSCs) effectively promote angiogenesis and drive functional myocardial regeneration. Human data are lacking. Aim To evaluate the feasibility and safety of a novel myocardial regeneration strategy using human WJMSCs as a unique, allogenic but immuno-privileged, off-the-shelf cellular therapeutic agent. Material and methods The inclusion criterion was first, large (LVEF ≤ 45%, CK-MB > 100 U/l) AMI with successful infarct-related artery primary percutaneous coronary intervention reperfusion (TIMI ≥ 2). Ten consecutive patients (age 32–65 years, peak hs-troponin T 17.3 ±9.1 ng/ml and peak CK-MB 533 ±89 U/l, sustained echo LVEF reduction to 37.6 ±2.6%, cMRI LVEF 40.3 ±2.7% and infarct size 20.1 ±2.8%) were enrolled. Results 30 × 106 WJMSCs were administered (LAD/Cx/RCA in 6/3/1) per protocol at ≈ 5–7 days using a cell delivery-dedicated, coronary-non-occlusive method. No clinical symptoms or ECG signs of myocardial ischemia occurred. There was no epicardial flow or myocardial perfusion impairment (TIMI-3 in all; cTFC 45 ±8 vs. 44 ±9, p = 0.51), and no patient showed hs-troponin T elevation (0.92 ±0.29 ≤ 24 h before vs. 0.89 ±0.28 ≤ 24 h after; decrease, p = 0.04). One subject experienced, 2 days after cell transfer, a transient temperature rise (38.9°C); this was reactive to paracetamol with no sequel. No other adverse events and no significant arrhythmias (ECG Holter) occurred. Up to 12 months there was one new, non-index territory lethal AMI but no adverse events that might be attributable to WJMSC treatment. Conclusions This study demonstrated the feasibility and procedural safety of WJMSC use as off-the-shelf cellular therapy in human AMI and suggested further clinical safety of WJMSC cardiac transfer, providing a basis for randomized placebo-controlled endpoint-powered evaluation.

Dimethyl Sulfoxide (DMSO) Increases Percentage of CXCR4(+) Hematopoietic Stem/Progenitor Cells, Their Responsiveness to an SDF-1 Gradient, Homing Capacities, and Survival.

Cryopreservation of bone marrow (BM), mobilized peripheral blood (mPB), and cord blood (CB) hematopoietic stem/progenitor cells (HSPCs) is a routine procedure before transplantation. The most commonly used cryoprotectant for HSPCs is dimethyl sulfoxide (DMSO). The objective of this study was to evaluate the influence of DMSO on surface receptor expression and chemotactic activities of HSPCs. We found that 10 min of incubation of human mononuclear cells (MNCs) with 10% DMSO significantly increases the percentage of CXCR4+, CD38+, and CD34+ cells, resulting in an increase of CD34+, CD34+CXCR4+, and CD34+CXCR4+CD38– subpopulations. Furthermore, DMSO significantly increased chemotactic responsiveness of MNCs and CXCR4+ human hematopoietic Jurkat cell line to a stromal cell-derived factor-1 (SDF-1) gradient. Furthermore, we demonstrated enhanced chemotaxis of human clonogenic progenitor cells to an SDF-1 gradient, which suggests that DMSO directly enhances the chemotactic responsiveness of early human progenitors. DMSO preincubation also caused lower internalization of the CXCR4 receptor. In parallel experiments, we found that approximately 30% more of DMSO-preincubated human CD45+ and CD45+CD34+ cells homed to the mouse BM 24 h after transplantation in comparison to control cells. Finally, we demonstrated considerably higher (25 days) survival of mice transplanted with DMSO-exposed MNCs than those transplanted with the control cells. We show in this study an unexpected beneficial influence of DMSO on HSPC homing and suggest that a short priming with DMSO before transplantation could be considered a new strategy to enhance cell homing and engraftment.