EIU in the rat promotes the potential of syngeneic retinal cells injected into the vitreous cavity to induce PVR.

PURPOSE: To determine whether syngeneic retinal cells injected in the vitreous cavity of the rat are able to initiate a proliferative process and whether the ocular inflammation induced in rats by lipopolysaccharide (LPS) promotes this proliferative vitreoretinopathy (PVR). METHODS: Primary cultured differentiated retinal Müller glial (RMG) and retinal pigmented epithelial (RPE) cells isolated from 8 to 12 postnatal Lewis rats were injected into the vitreous cavity of 8- to 10-week-old Lewis rats (10(5) cells/eye in 2 microlieter sterile saline), with or without the systemic injection of 150 microgram LPS to cause endotoxin-induced uveitis (EIU). Control groups received an intravitreal injection of 2 microliter saline. At 5, 15, and 28 days after cell injections, PVR was clinically quantified, and immunohistochemistry for OX42, ED1, vimentin (VIM), glial fibrillary acidic protein (GFAP), and cytokeratin was performed. RESULTS: The injection of RMG cells, alone or in combination with RPE cells, induced the preretinal proliferation of a GFAP-positive tissue, that was enhanced by the systemic injection of LPS. Indeed, when EIU was induced at the time of RMG cell injection into the vitreous cavity, the proliferation led to retinal folds and localized tractional detachments. In contrast, PVR enhanced the infiltration of inflammatory cells in the anterior segment of the eye. CONCLUSIONS: In the rat, syngeneic retinal cells of glial origin induce PVR that is enhanced by the coinduction of EIU. In return, vitreoretinal glial proliferation enhanced the intensity and duration of EIU.

Neues aus Diagnostik und Therapie der spinalen Erkrankungen [Novel aspects of diagnostics and therapy of spinal cord diseases].

BACKGROUND: Both non-traumatic and traumatic spinal cord injuries have in common that a relatively minor structural lesion can cause profound sensorimotor and autonomous dysfunction. Besides treating the cause of the spinal cord injury the main goal is to restore lost function as far as possible. AIM: This article provides an overview of current innovative diagnostic (imaging) and therapeutic approaches (neurorehabilitation and neuroregeneration) aiming for recovery of function after non-traumatic and traumatic spinal cord injuries. MATERIAL AND METHODS: An analysis of the current scientific literature regarding imaging, rehabilitation and rehabilitation strategies in spinal cord disease was carried out. RESULTS: Novel magnetic resonance imaging (MRI) based techniques (e.g. diffusion-weighted MRI and functional MRI) allow visualization of structural reorganization and specific neural activity in the spinal cord. Robotics-driven rehabilitative measures provide training of sensorimotor function in a targeted fashion, which can even be continued in the homecare setting. From a preclinical point of view, defined stem cell transplantation approaches allow for the first time robust structural repair of the injured spinal cord. CONCLUSION: Besides well-established neurological and functional scores, MRI techniques offer the unique opportunity to provide robust and reliable "biomarkers" for restorative therapeutic interventions. Function-oriented robotics-based rehabilitative interventions alone or in combination with stem cell based therapies represent promising approaches to achieve substantial functional recovery, which go beyond current rehabilitative treatment efforts.

The Nlrp3 inflammasome regulates acute graft-versus-host disease.

The success of allogeneic hematopoietic cell transplantation is limited by acute graft-versus-host disease (GvHD), a severe complication accompanied by high mortality rates. Yet, the molecular mechanisms initiating this disease remain poorly defined. In this study, we show that, after conditioning therapy, intestinal commensal bacteria and the damage-associated molecular pattern uric acid contribute to Nlrp3 inflammasome-mediated IL-1β production and that gastrointestinal decontamination and uric acid depletion reduced GvHD severity. Early blockade of IL-1β or genetic deficiency of the IL-1 receptor in dendritic cells (DCs) and T cells improved survival. The Nlrp3 inflammasome components Nlrp3 and Asc, which are required for pro-IL-1β cleavage, were critical for the full manifestation of GvHD. In transplanted mice, IL-1β originated from multiple intestinal cell compartments and exerted its effects on DCs and T cells, the latter being preferentially skewed toward Th17. Compatible with these mouse data, increased levels of active caspase-1 and IL-1β were found in circulating leukocytes and intestinal GvHD lesions of patients. Thus, the identification of a crucial role for the Nlrp3 inflammasome sheds new light on the pathogenesis of GvHD and opens a potential new avenue for the targeted therapy of this severe complication.

Long-term follow-up of patients with follicular lymphoma receiving single-agent rituximab at two different schedules in trial SAKK 35/98.

PURPOSE: We report the long-term results of a randomized clinical trial comparing induction therapy with once per week for 4 weeks single-agent rituximab alone versus induction followed by 4 cycles of maintenance therapy every 2 months in patients with follicular lymphoma. PATIENTS AND METHODS: Patients (prior chemotherapy 138; chemotherapy-naive 64) received single-agent rituximab and if nonprogressive, were randomly assigned to no further treatment (observation) or four additional doses of rituximab given at 2-month intervals (prolonged exposure). RESULTS: At a median follow-up of 9.5 years and with all living patients having been observed for at least 5 years, the median event-free survival (EFS) was 13 months for the observation and 24 months for the prolonged exposure arm (P < .001). In the observation arm, patients without events at 8 years were 5%, while in the prolonged exposure arm they were 27%. Of previously untreated patients receiving prolonged treatment after responding to rituximab induction, at 8 years 45% were still without event. The only favorable prognostic factor for EFS in a multivariate Cox regression was the prolonged rituximab schedule (hazard ratio, 0.59; 95% CI, 0.39 to 0.88; P = .009), whereas being chemotherapy naive, presenting with stage lower than IV, and showing a VV phenotype at position 158 of the Fc-gamma RIIIA receptor were not of independent prognostic value. No long-term toxicity potentially due to rituximab was observed. CONCLUSION: An important proportion of patients experienced long-term remission after prolonged exposure to rituximab, particularly if they had no prior treatment and responded to rituximab induction.

Preparation and analysis of fetal liver extracts.

The aim of this work is to describe the techniques that have been used for preparation and analysis of whole fetal liver extracts destined for in utero transplantation. Nine fetal livers between 12 and 17 weeks of gestation were prepared: cell counts and assessment of the hematopoietic cell viability were performed on cell suspensions. Hepatocytes represented 40 to 80% of the whole cell population. The remaining cells were constituted by hematopoietic cells (mainly erythroblasts), as well as by endothelial cells. The latter expressed CD34 on their surface, interfering with the assessment of CD34+ hematopoietic cells by flow cytometry. Direct visual morphologic control using alkaline phosphatase anti-alkaline phosphatase techniques was needed to differentiate hematopoietic from extra-hematopoietic CD34+ cells. Between 3.0 and 34.6 x 10(6) CD34+ viable hematopoietic cells were collected per fetal liver. Adequate differentiation of these cells into burst-forming units erythroid (BFU-E), colony-forming units granulocyte-macrophage (CFU-GM), and colony-forming units granulocyte erythroid macrophage megakaryocyte (CFU-GEMM) has been shown for each sample in clonogeneic cultures. In conclusion, fetal liver is a potential source of hematopoietic stem cells. Their numeration, based on the presence of CD34, is hampered by the expression of this antigen on other cells contained in the liver cell extract, in particular endothelial cells.

Functional late outgrowth endothelial progenitors isolated from peripheral blood of burned patients.

BACKGROUND: Bioengineered skin substitutes are increasingly considered as a useful option for the treatment of full thickness burn injury. Their viability following grafting can be enhanced by seeding the skin substitute with late outgrowth endothelial progenitor cells (EPCs). However, it is not known whether autologous EPCs can be obtained from burned patients shortly after injury. METHODS: Late outgrowth EPCs were isolated from peripheral blood sampled obtained from 10 burned patients (extent 19.6±10.3% TBSA) within the first 24h of hospital admission, and from 7 healthy subjects. Late outgrowth EPCs were phenotyped in vitro. RESULTS: In comparison with similar cells obtained from healthy subjects, growing colonies from burned patients yielded a higher percentage of EPC clones (46 versus 17%, p=0.013). Furthermore, EPCs from burned patients secreted more vascular endothelial growth factor (VEGF) into the culture medium than did their counterparts from healthy subjects (85.8±56.2 versus 17.6±14pg/mg protein, p=0.018). When injected to athymic nude mice 6h after unilateral ligation of the femoral artery, EPCs from both groups of subjects greatly accelerated the reperfusion of the ischaemic hindlimb and increased the number of vascular smooth muscle cells. CONCLUSIONS: The present study supports that, in patients with burns of moderate extension, it is feasible to obtain functional autologous late outgrowth EPCs from peripheral blood. These results constitute a strong incentive to pursue approaches based on using autotransplantation of these cells to improve the therapy of full thickness burns.

Candida krusei--a serious complication in patients with hematological malignancies: successful treatment with caspofungin.

Candida krusei infections are serious complications in neutropenic patients with hematological malignancies. We report the successful treatment of C. krusei infection with caspofungin in 3 allogeneic hematopoietic stem cell transplant recipients and 1 patient with induction chemotherapy for acute myeloid leukemia.

Genetic Polymorphisms and Susceptibility to Fungal Infections

Invasive fungal infections (IFI) are life-threatening diseases that are of particular concern in specific debilitated or immunosuppressed populations. Invasive candidiasis (IC) is the most frequent of the IFI, being one of the major causes of nosocomial bloodstream infection and a feared complication in patients with recurrent gastrointestinal surgery or prolonged stay in the intensive-care unit [1,2]. Patients with hematological malignancies or prolonged chemotherapy-induced neutropenia, and those with allogeneic hematopoietic stem cell transplantation (allo-HSCT), represent the groups at highest risk for developing invasive aspergillosis (IA), which is associated with a high mortality rate despite the increasing availability of antifungal therapies [3,4]. An increasing incidence of IA has also been reported in non-neutropenic immunosuppressed populations such as solid-organ transplant recipients or steroid-treated patients with chronic pulmonary diseases [5]. Early diagnosis of IFI is crucial for improving chances of survival [6], but is particularly challenging owing to the lack of reliable diagnostic methods [7,8]. Significant efforts during the last few decades have focused on the prevention of these severe complications. Antifungal prophylaxis in high-risk patients has been shown to reduce the incidence of IA in patients with onco-hematological malignancies [9] and that of IC in surgical intensive-care unit patients [10]. However, its widespread use raises concerns about costs, toxicity, and the risk of emergence of resistant fungal species such as non-Aspergillus moulds or non-albicansCandida spp. [4,11,12]. Prophylactic strategies usually rely on the identification of host risk factors resulting from clinical conditions (type and duration of immunosuppression, underlying diseases, and extrinsic interventions) [8,13]. Recent advances in the field of immunogenetics may change our perspective of, and approach to, preventive strategies with the identification of subgroups of patients exhibiting a genetic predisposition to IFI.

Inducible gene and shRNA expression in resident hematopoietic stem cells in vivo.

Hematopoietic stem cells (HSC) are probably the best understood somatic stem cells and often serve as a paradigm for other stem cells. Nevertheless, most current techniques to genetically manipulate them in vivo are either constitutive and/or induced in settings of hematopoietic stress such as after irradiation. Here, we present a conditional expression system that allows for externally controllable transgenesis and knockdown in resident HSCs, based on a lentiviral vector containing a tet-O sequence and a transgenic mouse line expressing a doxycyclin-regulated tTR-KRAB repressor protein. HSCs harvested from tTR-KRAB mice are transduced with the lentiviral vector containing a cDNA (i.e., Green Fluorescent Protein (GFP)) and/or shRNA (i.e., p53) of interest and then transplanted into lethally irradiated recipients. While the vector is effectively repressed by tTR-KRAB during homing and engraftment, robust GFP/shp53 expression is induced on doxycyclin treatment in HSCs and their progeny. Doxycylin-controllable transcription is maintained on serial transplantation, indicating that repopulating HSCs are stably modified by this approach. In summary, this easy to implement conditional system provides inducible and reversible overexpression or knock down of genes in resident HSCs in vivo using a drug devoid of toxic or activating effects.

Impact of Balanced or Unbalanced Karyotype At Diagnosis On Prognosis of CML: Long-Term Observation From 1346 Patients of the Randomized CML Study IV

Introduction: Acquired genetic instability in chronic myeloid leukemia (CML) as a consequence of the translocation t(9;22)(q34;q11) and the resulting BCR-ABL fusion causes the continuous acquisition of additional chromosomal aberrations and mutations and thereby progression to accelerated phase (AP) and blast crisis (BC). At least 10% of patients in chronic phase (CP) CML show additional alterations at diagnosis. This proportion rises during the course of the disease up to 80% in BC. Acquisition of chromosomal changes during treatment is considered as a poor prognostic indicator, whereas the impact of chromosomal aberrations at diagnosis depends on their type. Patients with major route additional chromosomal alterations (major ACA: +8, i(17)(q10), +19, +der(22)t(9;22)(q34;q11) have a worse outcome whereas patients with minor route ACA show no difference in overall survival (OS) and progression-free survival (PFS) compared to patients with the standard translocation, a variant translocation or the loss of the Y chromosome (Fabarius et al., Blood 2011). However, the impact of balanced vs. unbalanced (gains or losses of chromosomes or chromosomal material) karyotypes at diagnosis on prognosis of CML is not clear yet. Patients and methods: Clinical and cytogenetic data of 1346 evaluable out of 1544 patients with Philadelphia and BCR-ABL positive CP CML randomized until December 2011 to the German CML-Study IV, a randomized 5-arm trial to optimize imatinib therapy by combination, or dose escalation and stem cell transplantation were investigated. There were 540 females (40%) and 806 males (60%). Median age was 53 years (range, 16-88). The impact of additional cytogenetic aberrations in combination with an unbalanced or balanced karyotype at diagnosis on time to complete cytogenetic and major molecular remission (CCR, MMR), PFS and OS was investigated. Results: At diagnosis 1174/1346 patients (87%) had the standard t(9;22)(q34;q11) only and 75 patients (6%) had a variant t(v;22). In 64 of 75 patients with t(v;22), only one further chromosome was involved in the translocation; In 8 patients two, in 2 patients three, and in one patient four further chromosomes were involved. Ninety seven patients (7%) had additional cytogenetic aberrations. Of these, 44 patients (3%) lacked the Y chromosome (-Y) and 53 patients (4%) had major or minor ACA. Thirty six of the 53 patients (2.7%) had an unbalanced karyotype (including all patients with major route ACA and patients with other unbalanced alterations like -X, del(1)(q21), del(5)(q11q14), +10, t(15;17)(p10;p10), -21), and 17 (1.3%) a balanced karyotype with reciprocal translocations [e.g. t(1;21); t(2;16); t(3;12); t(4;6); t(5;8); t(15;20)]. After a median observation time of 5.6 years for patients with t(9;22), t(v;22), -Y, balanced and unbalanced karyotype with ACA median times to CCR were 1.05, 1.05, 1.03, 2.58 and 1.51 years, to MMR 1.31, 1.51, 1.65, 2.97 and 2.07 years. Time to CCR and MMR was longer in patients with balanced karyotypes (data statistically not significant). 5-year PFS was 89%, 78%, 87%, 94% and 69% and 5-year OS 91%, 87%, 89%, 100% and 73%, respectively. In CML patients with unbalanced karyotype PFS (p<0.001) and OS (p<0.001) were shorter than in patients with standard translocation (or balanced karyotype; p<0.04 and p<0.07, respectively). Conclusion: We conclude that the prognostic impact of additional cytogenetic alterations at diagnosis of CML is heterogeneous and consideration of their types may be important. Not only patients with major route ACA at diagnosis of CML but also patients with unbalanced karyotypes identify a group of patients with shorter PFS and OS as compared to all other patients. Therefore, different therapeutic options such as intensive therapy with the most potent tyrosine kinase inhibitors or stem cell transplantation are required.

Epstein-Barr virus-related post-transplant lymphoproliferative disorder in solid organ transplant recipients.

Epstein-Barr virus (EBV) contributes to the pathogenesis of post-transplant lymphoproliferative disease (PTLD) in more than 70% of cases. EBV DNAemia surveillance has been reported to assist in the prevention and treatment of PTLD in hematopoietic stem-cell transplantation (HSCT) recipients. Derived from experience in HSCT and taking into account that PCR-based EBV monitoring techniques are currently available in most solid organ transplant (SOT) centres, there is a great interest in EBV surveillance and prevention of PTLD in SOT recipients. In the present document we have tried to address from a practical perspective different important topics regarding the prevention and management of EBV-related PTLD in SOT. To this end, available information on SOT was analysed and combined with potentially useful data from HSCT and expert observations. The document is therefore structured according to different specific questions, each of them culminating in a consensus opinion of the panel of European experts, grading the answers according to internationally recognized levels of evidence. The addressed issues were grouped under the following topics. (i) Timing and epidemiological data of PTLD. Prophylaxis guided by clinical risk factors of early and late PTLD in SOT. (ii) Relationship of EBV DNAemia load monitoring and the development of PTLD in solid organ transplant recipients. (iii) Monitoring of EBV DNAemia after SOT. Which population should be monitored? What is the optimal timing of the monitoring? (iv) Management of SOT recipients with persistent and/or increasing EBV DNAemia.

Hémato-oncologie pédiatrique: de la biologie cellulaire aux traitements ciblés et individualisés [Pediatric hemato-oncology: from cellular biology to individualized targeted therapies].

Progresses in pediatric oncology over the last decades have been dramatic and allow current cure rates above 80%. There are mainly due to multicentre clinical trials aiming at optimizing chemotherapy protocols as well as local therapies in a stepwise approach. Most of the new anticancer drugs currently in development are based on targeted therapies, directed to specific targets present only in or on tumor cells, like growth factor receptors, mechanisms involved in proliferation, DNA repair, apoptosis, tumor invasion or angiogenesis. Concerning bone marrow transplantation also, new strategic approaches are in advanced development. They aim at reducing treatment induced toxicity and enhancing efficacy at the same time. This short paper would like to point out these new technologies, which should be known by the general practitioner.

FGF-2 controls the differentiation of resident cardiac precursors into functional cardiomyocytes.

Recent evidence suggests that the heart possesses a greater regeneration capacity than previously thought. In the present study, we isolated undifferentiated precursors from the cardiac nonmyocyte cell population of neonatal hearts, expanded them in culture, and induced them to differentiate into functional cardiomyocytes. These cardiac precursors appear to express stem cell antigen-1 and demonstrate characteristics of multipotent precursors of mesodermal origin. Following infusion into normal recipients, these cells home to the heart and participate in physiological and pathophysiological cardiac remodeling. Cardiogenic differentiation in vitro and in vivo depends on FGF-2. Interestingly, this factor does not control the number of precursors but regulates the differentiation process. These findings suggest that, besides its angiogenic actions, FGF-2 could be used in vivo to facilitate the mobilization and differentiation of resident cardiac precursors in the treatment of cardiac diseases.

Current multiple myeloma treatment strategies with novel agents: a European perspective.

The treatment of multiple myeloma (MM) has undergone significant developments in recent years. The availability of the novel agents thalidomide, bortezomib, and lenalidomide has expanded treatment options and has improved the outcome of patients with MM. Following the introduction of these agents in the relapsed/refractory setting, they are also undergoing investigation in the initial treatment of MM. A number of phase III trials have demonstrated the efficacy of novel agent combinations in the transplant and nontransplant settings, and based on these results standard induction regimens are being challenged and replaced. In the transplant setting, a number of newer induction regimens are now available that have been shown to be superior to the vincristine, doxorubicin, and dexamethasone regimen. Similarly, in the front-line treatment of patients not eligible for transplantation, regimens incorporating novel agents have been found to be superior to the traditional melphalan plus prednisone regimen. Importantly, some of the novel agents appear to be active in patients with high-risk disease, such as adverse cytogenetic features, and certain comorbidities, such as renal impairment. This review presents an overview of the most recent data with these novel agents and summarizes European treatment practices incorporating the novel agents.