Search

nema

The patient was admitted for urgent coronary angiography following an acute anterior ST segment elevation myocardial reinfarction (STEMI) caused by acute stent thrombosis. A stent had been implanted 10 days prior to the reinfarction for an acute anterior STEMI. However, the patient had stopped taking ticagrelor post-discharge. Primary percutaneous coronary intervention of the left anterior descending artery was performed. Subsequently, due to a high C-reactive protein (CRP) level, 3 CRP apheresis sessions were performed, with the first session starting 12 h after the onset of symptoms. A significant drop in CRP was noted after each apheresis. The post-procedural course was uneventful.

Background/Aim. Intravenous drug users (IDUs) are still a high risk-group for cross-reacting blood-borne infections, for vertical pathogen transmission as well as for potentially blood/plasma donation (especially as ?paid? donors). The aim of our study was to establish the profile of opiate addict and prevalence of blood-borne pathogens ? Hepatitis B virus (HBV), Hepatitis C virus (HCV) and Human Immunodeficiency Virus (HIV) among 99 patients on substitution therapy with methadone and buprenorphine from Sumadia District. Methods. The Treatment Demand Indicator (TDI) of Pompidou-questionnaire was used to assess the history of drug abuse and risk behavior. All blood samples were tested for HBV surface antigen (HBsAg), anti-HCV antibody (anti-HCV) and HIV antigen/antibody (HIVAg/ Ab) by Enzyme-Linked ImmunoSorbent Assay (ELISA) or Chemiluminescent Immuno-Assay (CIA). Investigations were also performed for HBV, HCV and HIV by molecular testing ? Polymerase Chain Reaction (PCR) method. Results. The majority of patients were males (81.8%), median age 32 (19?57) years, lived in a city (99%), unemployed (58.6%), with finished secondary school (67.7%), unsafe injecting practices (34.3%) and never previously tested for HBV (39.4%), HCV (36.4%) nor HIV (28.3%); only 4% of them previously got HBV-vaccine. The complementary testing resulted with following results: HBV ELISA/CIA and PCR negativity for 66 patients and positive results (by ELISA/CIA and PCR) for 19 patients. However, a difference was observed in the ELISA/CIAnegative/ PCR-positive result for 12 and ELISA/CIApositive/ PCR-negative for two patients respectively. Further, the negative results for HCV (ELISA/CIA and PCR testing) were found in 15 IDUs and positive results (using both methods) were found in 58 patients. Different results for ELISA/CIA-negative / PCR-positive results were found in 11 IDUs and ELISA/CIA-positive/PCR ? negative results were found in 15 patients. All investigated IDUs were negative for HIV (ELISA/CIA and PCR testing) and for pathogens of opportunistic infection (Cryptococcus neoformans; Pneumocystis carinii; PCR testing), as well as for West Nile Virus (PCR testing). Just one IDU was positive for syphilis (ELISA and confirmatory testing). Conclusion. Our study demonstrated that the positivity for HBV and HCV is still very high (33.4% and 84.8%, respectively) in IDUs. Thus, we suggest that drug users have to be periodically screened using a complementary serological/molecular testing ? concerning differences/discrepancies in the results obtained using these methods.

Stem cells could be defined as cells capable for self-renewal with high proliferative capacity and extensive potential to differentiate into blood cells or some somatic cell types - ?plasticity? due to ?trans-differentiation? - such as osteocytes, chondrocytes, hepatocytes, myocytes, cardiomyocytes and even endothelial cells. Recent increasing clinical use of various cell-mediated therapeutic approaches has resulted in amplified needs for both stem cells and operating procedures to get a minimized cell damages during collection, purification and cryopreservation. The aim of cell harvesting procedures is to obtain the best stem cells yield, high purity and good viability/clonogenicity. The goal of optimized cryoinvestigation protocols is to minimize cell injuries during the freeze/thaw process (cryoinjury). Despite the fact that different stem cells collection protocols and cell freezing practice are already in routine use, a lot of questions related to the optimal blood stem cells harvesting, purification and cryopreservation are still unresolved.

Background: In patients with ST-elevation myocardial infarction (STEMI), C-reactive protein (CRP) levels are associated with larger infarct size, transmural extent, and poor function of left ventricle and independently predict 30-day mortality. CRP-apheresis following STEMI showed to be feasible, safe, and has significant beneficial effect both on myocardial infarction size and wall motion. To the best of our knowledge, this is only the second published clinical evaluation of the efficacy and safety of selective CRP-apheresis in the STEMI treatment using Spectra-Optia and Pentrasorb CRP-adsorber systems. Case Report: A 53-year-old female was referred with anterior STEMI. After percutaneous coronary intervention, patient received standard post-STEMI therapy according to current guidelines. Selective therapeutic plasma exchange (TPE) was performed using Spectra-Optia (Terumo BCT; USA) and Pentrasorb CRP-adsorber (Pentracor GmbH; Germany) systems. Antecubital veins were used for vascular access and acid-citrate-dextrose solution (ACD formula A; total volume = 1,026 mL) was utilized as anticoagulant. The volume of processed blood was 15,600 mL. The removed “natural” plasma (total volume = 8,329 mL) was replaced with CRP-depleted autologous plasma (total volume = 8,085 mL). This intensive TPE-treatment was well tolerated, without adverse effects, or complications. The CRP plasma levels were: initial = 4.2 mg/L 6 h after acute myocardial infarction (AMI), pre-apheresis = 16.4 mg/L, and post-apheresis = 4.59 mg/L (CRP-depletion = 72%). There were neither significant changes observed in biochemistry nor any alterations in plasma hemostatic activity investigated before and after CRP-adsorption performed. Conclusion: Early performed CRP-apheresis is a promising innovative therapeutic approach for STEMI treatment that could provide a reduced size of infarction zone – with inferior occurrence of heart failure after AMI. However, precise and complete evaluation of the efficacy and safety of this treatment requires further multicenter randomized and larger clinical studies.

The common signs of canine babesiosis caused by an infection with Babesia canis are fever, anorexia, lethargy, pulse alterations, anemia, and occasionally mild icterus. Dogs with these clinical signs can be divided into two groups: those with acute-phase reaction and those with systemic inflammatory response syndrome (SIRS). Factors associated with the occurrence of SIRS in canine babesiosis have not been thoroughly researched. This article outlines a cross-sectional study of 54 client-owned dogs with an acute B. canis infection, and evaluates the differences in age, gender, laboratory findings, parasite load, and seroreactivity against B. canis between the SIRS and the SIRS-free dogs. We have analyzed a complete blood count, serum biochemistry, serum amyloid A, ceruloplasmin, paraoxonase-1, serology, and PCR testing using standard methodologies. The frequency of SIRS among the investigated dogs reached 0.59. Male dogs and those seronegative against B. canis, were more frequent in the SIRS group, whilst age and parasite load could not be associated with the presence of SIRS. Dogs with SIRS had a lower count of total leukocytes, neutrophils, lymphocytes, and monocytes, and a lower concentration of iron and bilirubin compared with SIRS-free dogs. No significant differences in the concentration of acute-phase proteins have been noticed to exist between the groups of dogs. Further, the seronegative dogs had a lower count of lymphocytes and monocytes and a higher parasite load than the seroreactive dogs. Multivariate logistic regression analysis has identified leukopenia (

Prognostic significance of immune microenvironment has been emphasized using the most advanced analysis, with consecutive attempts to reveal prognostic impact of this findings. The aim of this study was to compare and define prognostic significance of clinical parameters, microvessel density (MVD) in tumour tissue and expression of CD44s as adhesive molecule on tumour cells in diffuse large B cell lymphoma-DLBCL, primary central nervous system DLBCL-CNS DLBCL and follicular lymphoma-FL. A total of 202 histopathological samples (115 DLBCL/65 FL/22 CNS DLBCL) were evaluated. Overall response (complete/partial remission) was achieved in 81.3 % DLBCL patients, 81.8 % primary CNS DLBCL and 92.3 % FL. Absolute lymphocyte count-ALC/Absolute monocyte count-AMC2.6 in DLBCL and ALC/AMC ≥ 4.7 in FL were associated with better event-free survival (EFS) and overall survival (OS) (p 0.05). In DLBCL, MVD 42 blood vessels/0.36 mm(2) correlated with primary resistant disease (p 0.0001), poorer EFS and OS (p = 0.014). High CD44s expression in FL correlated with inferior EFS and OS (p 0.01). In DLBCL, multivariate Cox regression analysis showed that ALC/AMC was independent parameter that affected OS (HR 3.27, 95 % CI 1.51-7.09, p = 0.003) along with the NCCN-IPI (HR 1.39, 95 % CI 1.08-1.79, p = 0.01). Furthermore, in FL, ALC/AMC mostly influenced OS (HR 5.21, 95 % CI 1.17-23.21, p = 0.03), followed with the FLIPI (HR 3.98, 95 % CI 1.06-14.95, p = 0.041). In DLBCL and FL, ALC/AMC is simple and robust tool that is, with current prognostic scores, able to define long-term survival and identify patients with inferior outcome. The introduction of immunochemotherapy might altered the prognostic significance of microenvionmental biomarkers (MVD and CD44s).

Background/Aim. Bacterial contamination of blood components, primarily platelet concentrates (PCs), has been identified as one of the most frequent infectious complications in transfusion practice. PC units have a high risk for bacterial growth/multiplication due to their storage at ambient temperature (20 ± 2°C). Consequences of blood contamination could be effectively prevented or reduced by pathogen inactivation systems. The aim of this study was to determine the Mirasol pathogen reduction technology (PRT) system efficacy in PCs using an artificial bacteria-contamination model. Methods. According to the ABO blood groups, PC units (n = 216) were pooled into 54 pools (PC-Ps). PC-Ps were divided into three equal groups, with 18 units in each, designed for an artificial bacteria-contamination. Briefly, PC-Ps were contaminated by Staphylococcus epidermidis, Staphylococcus aureus or Escherichia coli in concentrations 102 to 107 colony forming units (CFU) per unit. Afterward, PC-Ps were underwent to inactivation by Mirasol PRT system, using UV (l = 265-370 nm) activated riboflavin (RB). All PC-Ps were assayed by BacT/Alert Microbial Detection System for CFU quantification before and after the Mirasol treatment. Samples from non-inactivated PC-P units were tested after preparation and immediately following bacterial contamination. Samples from Mirasol treated units were quantified for CFUs one hour, 3 days and 5 days after inactivation. Results. A complete inactivation of all bacteria species was obtained at CFU concentrations of 102 and 103 per PC-P unit through storage/ investigation period. The most effective inactivation (105 CFU per PC-P unit) was obtained in Escherichia coli setting. Contrary, inactivation of all the three tested bacteria species was unworkable in concentrations of ≥ 106 CFU per PC-P unit. Conclusion. Efficient inactivation of investigated bacteria types with a significant CFU depletion in PC-P units was obtained - 3 Log for all three tested species, and 5 Log for Escherichia coli. The safety of blood component therapy, primarily the clinical use of PCs can be improved using the Mirasol PRT system.

Recently, a guanosine analog, 7-allyl-7,8-dihydro-8-oxo-guanosine (loxoribine), has been identified as a selective Toll-like receptor (TLR)7 agonist. Bearing in mind the controversy regarding the expression of TLR7 by human myeloid dendritic cells (DCs) and its significance for functions of these cells, the goal of this study was to investigate the effect of loxoribine on differentiation, maturation and functions of human monocyte-derived (Mo)DCs. Immature MoDCs were obtained by cultivation of monocytes for 6 days with recombinant granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin (IL)-4. These cells were stimulated with loxoribine (250 μM) for an additional 48 h. Phenotypic properties of MoDCs were determined by flow cytometry, cytokine production was assayed by ELISA, whereas their allostimulatory capability was tested using a mixed leukocyte reaction. We showed that loxoribine up-regulated the expression of TLR7, CD40, CD54, CD80, CD83 and CCR7 and stimulated the production of IL-12, IL-23, IL-27 and IL-10 by MoDCs, whereas the level of interferon (IFN)-β was not modulated. Allogeneic CD4(+)T cells in co-culture with loxoribine-treated MoDCs proliferated more strongly, at lower DC/CD4(+)T-cell ratio (1:80), and secreted significantly higher levels of IL-17 and IFN-γ compared to the cultures with control MoDCs. The stimulatory effect of loxoribine on T helper (Th)1 polarization capability of MoDCs was further potentiated by ligation of CD40. In conclusion, our results show that loxoribine stimulated differentiation, maturation, allostimulatory as well as Th1 and Th17 polarization capability of human MoDCs and suggests that these effects might be associated with up-regulation of TLR7 expression, but not increased IFN-β production.

Langerhans' cells (LCs) represent a specific subset of dendritic cells (DCs) which are important for detecting and processing pathogens that penetrate the skin and epithelial barriers. The aim of our study was to explain what makes their in vitro counterparts - monocyte-derived Langerhans'-like cells (MoLCs) - unique compared with monocyte-derived dendritic cells (MoDCs). Immature MoDCs were generated by incubating peripheral blood monocytes with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-4. The addition of transforming growth factor-β (TGF-β) to this cytokine cocktail resulted in the generation of MoLCs. MoLCs showed a lower expression of CD83, CD86, HLA-DR and CCR7 compared with MoDCs, regardless of their maturational status. Both immature and mature MoLCs secreted higher quantities of IL-23 compared with MoDCs and this finding correlated with a higher secretion of IL-17 in co-culture of MoLCs with allogeneic CD4(+) T cells. Mature MoLCs, which produced higher levels of IL-12 and lower levels of IL-10 compared with mature MoDCs, were more potent at inducing interferon-γ (IFN-γ) production by CD4(+) T cells in the co-culture system. In conclusion, the finding that mature MoLCs stimulate stronger T-helper 1 and T-helper 17 immune responses than mature MoDCs, makes them better candidates for use in the preparation of anti-tumour DC vaccines.

To date, three types of dental stem cells have been isolated: Dental Pulp Stem Cells (DPSC), Stem Cells From Human Exfoliated Deciduous Teeth (SHED) and Immature Dental Pulp Stem Cells (IDPC). These dental stem cells are considered as mesenchymal stem cells. They reside within the perivascular niche of dental pulp. They are highly proliferative, clonogenic, multipotent and are similar to mesenchymal Bone Marrow Stem Cells (BMSC). Also, they have high plasticity and can be easy isolated. The expressions of the alkaline phosphatase gene, dentin matrix protein 1 and dentinsialophosphoprotein are verified in these cells. Analyses of gene expression patterns indicated several genes which encode extracellular matrix components, cell adhesion molecules, growth factors and transcription regulators, cell signaling, cell communication or cell metabolism. In both conditions, in vivo and in vitro, these cells have the ability to differentiate into odontoblasts, chondrocytes, osteoblasts, adipocytes, neurons, melanocytes, smooth and skeletal muscles and endothelial cells. In vivo, after implantation, they have shown potential to differentiate into dentin but also into tissues like bone, adipose or neural tissue. In general, DPSCs are considered to have antiinflammatory and immunomodulatory abilities. After being grafted into allogenic tissues these cells are ableto induce immunological tolerance. Immunosuppressive effect is shown through the ability to inhibit proliferation of T lymphocytes. Dental pulp stem cells open new perspectives in therapeutic use not only in dentin regeneration, periodontal tissues and skeletoarticular, tissues of craniofacial region but also in treatment of neurotrauma, autoimmune diseases, myocardial infarction, muscular dystrophy and connective tissue damages.

Hematopoiesis is a permanent and complex event in which a spectrum of different mature blood cells from a small population of toti/pluri/multipotent stem cells (SCs) are produced through a variety of proliferative and differentiative processes. Hematopoietic SCs are defined as the cells with extensive self–renewal and proliferative potential, together with their ability to differentiate into all blood–cell lineages. Many studies have demonstrated that a multifactorious network of interactive cytokines and other blood–derived mediators regulate the survival, maturation, and proliferation of SCs .

This chapter is dealing with identification of cancer stem cell markers, their latest classification, function in normal and cancer stem cells (CSCs), and their use in development of novel targeted antitumor therapy. It was difficult to prove the CSCs existence, unless the in vivo and in vitro experiments have been done supporting the theory that they have common clonogenic origin and perpetuate always the same phenotypic marker(s) on their surface, being also able to induce production of original tumor in transplanted NOD/SCID mice. The cancer stem cells so far have been found in most of human tissues and checked as well, in agar, for anchorage growth. Today they can be isolated using magnetic beads coated with antibodies targeted against specific markers.

Over the last 100 years, many studies have been performed to determine the biochemical and histopathological phenomena that mark the origin of neoplasms. At the end of the last century, the leading paradigm, which is currently well rooted, considered the origin of neoplasms to be a set of genetic and/or epigenetic mutations, stochastic and independent in a single cell, or rather, a stochastic monoclonal pattern. However, in the last 20 years, two important areas of research have underlined numerous limitations and incongruities of this pattern, the hypothesis of the so-called cancer stem cell theory and a revaluation of several alterations in metabolic networks that are typical of the neoplastic cell, the so-called Warburg effect. Even if this specific “metabolic sign” has been known for more than 85 years, only in the last few years has it been given more attention; therefore, the so-called Warburg hypothesis has been used in multiple and independent surveys. Based on an accurate analysis of a series of considerations and of biophysical thermodynamic events in the literature, researchers demonstrated a homogeneous pattern of the cancer stem cell theory, of the Warburg hypothesis and of the stochastic monoclonal pattern; this pattern could contribute considerably as the first basis of the development of a new uniform theory on the origin of neoplasms. Thus, a new possible epistemological paradigm is represented considering the Warburg effect as a specific “metabolic sign.” This sign reflects the stem origin of the neoplastic cell, where, in this specific metabolic order, an essential reason for the genetic instability that is intrinsic to the neoplastic cell is defined.

This chapter will teach you about origin, classification, features of stem cells, and fundaments of stem cell therapy as the segment of cellular-based therapy. Generally, the Stem Cell (SC)—compartment is divided into embryonic and tissue-specific or adult SCs. Paul Niehans M.D. (1882–1971), the originator of cell therapy, wrote: “Cellular therapy is a method of treating the whole organism on a biological basis, capable of revitalizing the human organism with its trillions of cells by bringing to it those embryonic or young cells which it needs. Cells from all organs are at our disposal; the doctor’s art is to choose the right cells. Selective cellular therapy offers new life to the ailing or diseased organism.”

The hematopoiesis is a continuous and complex event in which blood cells from a small number of stem cells (SCs) are produced through proliferation and differentiation. A complex network of interactive substances and factors organize and protect the survival of toti/pluri/multipotent SC, maturation (differentiation), and multiplication (proliferation). Namely, differentiation and proliferation of SCs in the bone marrow (BM) are regulated by the extracellular matrix and microenvironment provided by stromal cells. These cells—including macrophages, fibroblasts, dendritic, endothelial, and other cells—stimulate hematopoietic SCs by producing growth factors like Flt3-ligand, c-kit-ligand or SC factor, a variety of interleukins, granulocyte-macrophage colony-stimulating factor (GM-CSF), and granulocyte colony-stimulating factor (G-CSF). Other cytokines secreted by stromal cells regulate the adhesion molecules positioned on SCs, allowing them to remain in the BM or migrate to an area where the respective cell type is needed.

A great body of evidence supports the statement that both genetic and epigenetic processes are responsible for tumor development. Indeed, alterations in DNA methylation, histone modifications, polycomb, miRNAs, and chromatin remodeling complex function are mechanisms that directly contribute to tumorigenesis. However, this chapter will summarize the most relevant genetic alterations, which contribute to the regulation of cancer stem cell features in tumor progression, metastasis, and response to chemotherapy.

Epigenetic changes have been linked to abnormal transcriptional regulations which may result in carcinogenesis. Indeed, alterations in DNA methylation, histone modifications, polycomb, miRNAs, and chromatin remodeling complex function are mechanisms that directly contribute to tumorigenesis. Interestingly, the epigenetic origins of some of the aberrant signals that operate in tumor progression facilitate their reversion by specific inhibitors. In consequence, targeting the stemness-like properties of this special population of cancer cells with agents that modify their epigenetic landscape can contribute to the sensitization of CSCs to chemotherapy, impeding tumor relapse. For all these reasons, it is a rapidly emerging field in oncology and might represent a promising strategy for cancer therapy in the future. From all of epigenetic phenomena, DNA methylation is the most extensively studied epigenetic mechanism. Aberrant patterns of DNA methylation (hypomethylation or hypermethylation) are considered significant features in the diagnosis and/or prognosis of cancers. There is increasing evidence that DNA hypermethylation in gene promoter regions and its association with polycomb complex proteins may promote carcinogenesis by blocking certain normal stem cell patterns from fully differentiating, and consequently perpetuating self-renewal of these stem cells.

Ever since from establishment of Cancer Stem Cell Theories, there was a permanent, strong effort to understand differences and similarities between distinctive types of normal, and between normal and cancer stem cells. A striking distinction between embryonic and adult stem cells is achieved, and a striking distinction between normal and CSC is obvious, although the knowledge on CSCs is still very limited despite interesting results. Is Cancer a disease of stem cells? There is an extraordinary diversity within the broad category of diseases known as a cancer. The cellular markers, the signaling pathways to the nucleus, the metabolic trajectories, and genetic changes vary in different tumors. It will be necessary to figure out different CSC profiles and find the best possible targeted treatment for each particular CSC. Thus, the fact that only a few cells within the tumor, the CSCs are tumorigenic and possess metastatic phenotype has implications for both therapy and research. Despite so many levels of diagnostic and therapeutic achievements, it is still a lot of work needed to clarify this issue. The development of novel technologies, such as genetic engineering, nanotechnology, antimitochondrial cancer therapy, magnetotherapy, immunotherapeutic approaches, and remote control drug delivery systems, today portrays the field of targeted anticancer therapy as the concept which is emerging as a fantastic array of possibilities for better understanding of the stemness. This chapter will summarize the current essential and future guidelines in bioengineering necessary to understand this entity from many points of views.

The existence of a potential primary central nervous system lymphoma-specific genomic signature that differs from the systemic form of diffuse large B cell lymphoma (DLBCL) has been suggested, but is still controversial. We investigated 19 patients with primary DLBCL of central nervous system (DLBCL CNS) using the TruSeq Amplicon Cancer Panel (TSACP) for 48 cancer-related genes. Next generation sequencing (NGS) analyses have revealed that over 80% of potentially protein-changing mutations were located in eight genes (CTNNB1, PIK3CA, PTEN, ATM, KRAS, PTPN11, TP53 and JAK3), pointing to the potential role of these genes in lymphomagenesis. TP53 was the only gene harboring mutations in all 19 patients. In addition, the presence of mutated TP53 and ATM genes correlated with a higher total number of mutations in other analyzed genes. Furthermore, the presence of mutated ATM correlated with poorer event-free survival (EFS) (p = 0.036). The presence of the mutated SMO gene correlated with earlier disease relapse (p = 0.023), inferior event-free survival (p = 0.011) and overall survival (OS) (p = 0.017), while mutations in the PTEN gene were associated with inferior OS (p = 0.048). Our findings suggest that the TP53 and ATM genes could be involved in the molecular pathophysiology of primary DLBCL CNS, whereas mutations in the PTEN and SMO genes could affect survival regardless of the initial treatment approach.

Hematopoiesis is an eventful and multifactorial continuous process in which a ­variety of blood cells are produced through proliferation and differentiation from a minor quantity of stem cells (SCs) [1]. A complex network of interactive matters and factors accomplishes the toti/pluri/multipotent SC survival, maturation, and multiplication. Namely, differentiation and proliferation of SCs in the bone marrow (BM) are regulated by the extracellular matrix and microenvironment provided by stromal cells [1].

This chapter is focused to engraftment and use of genetic markers in cellular therapy. It is concisely explaining conditions for homing in recipient and the significance of both in Tissue Engineering and cellular therapy.

The MHC is a large and stable region mapped to the short arm of the chromosome 6, encoding genes that have a lot of functions in immune and nonimmune response. MHC includes regions for the well-known and the most polymorphic until now discovered gene system, the human leukocyte antigen (HLA) genes. The extreme polymorphism of the HLA system derives from the existence of multiple alleles at several loci. It is estimated that more than 100 million different phenotypes can result from all combinations of alleles in the HLA system [1–5]. HLA genes are autosomal with codominant expression, inherited regularly as a haplotype. Since progeny receives one chromosome (haplotype) from each parent, four combinations of haplotypes are possible in newborn.

They have the unique ability of self-renewal and plasticity, e.g., to multiply for a long time without a change and to produce cells that differentiate into specialized structures. New stem cells can be created to replenish stem cell population.

The pluripotency of stem cells from different sources is the subject of controversies and criticism, but as one of the most prominent features of these cells is also envisioned as a powerful therapeutic approach. Adult stem cells reside in most mammalian tissues, but the extent to which they contribute to normal homeostasis and repair varies widely.

Animal models have demonstrated that transplanted embryonic cells are exposed to the immune reactions similar to those acting on organ transplants, hence immunosuppression of the recipient is generally required. It is, however, possible to obtain embryonic stem cells that are genetically identical to the patient’s own cells. The nucleus from the patient’s somatic cell is transferred into an egg after removal of the egg’s own genetic material (a technique known as nuclear transfer or therapeutic cloning). Under specific condition the egg will use genetic information from the patient’s somatic cell in organizing the formation of a blastocyst which in turn generates embryonic stem cells. These cells have a genetic composition identical to that of patient, are suitable for stem cell therapy, will generate patient’s own proteins, and escape the danger for “self-attack” and immune rejection [1].

Adult stem cells are stem cells that can be derived from different parts of the body and, depending on where they are from, have different properties. They exist in several different tissues including bone marrow, blood, liver, nasal mucosa, skin, and the brain. Some studies have suggested that adult stem cells are very versatile and can develop into many different cell types. Adult stem cells have already been used for more than 20 years as bone-marrow transplants to reconstitute the immune systems of patients with cancer and to treat blood cancers such as leukemia [1, 2]. Using the body’s own stem cells means, the immune system’s rejection reflex will not be aroused.

Stem cell biology is an extremely active field in biology, not only from a scientific but also from the political, social, and ethical perspective. It is well known that ethical aspect involves for many strong argument that using embryonic stem cells is equal to homicide. The other argument is: How one can give embryonic stem cells to somebody, when the immune system will not tolerate “nonself”? This obstacle was overcome by the concept of therapeutic cloning, in which the nucleus of stem cell (through microsurgery) is replaced by patient’s nucleus (nuclear transfer). In that way, embryonic body (which is in cytoplasm of the zygot and will give stem cells) will be “supervised” by patient’s genetic codes and orchestrate patient’s coding of specific proteins. They will not be foreign to immune system and will not affect the engraftment.

Among the most investigated are the mechanisms that regulate stem cell function in the nervous and hematopoietic systems. Therefore, hematopoietic stem cells, which give rise to all blood and immune system cells, and neural crest stem cells, which give rise to the peripheral nervous system, are among the best-characterized stem cells. We are just beginning to understand how their functions are regulated. The conserved mechanisms have long been hypothesized as the mode of stem cell regulation. However, testing this requires interdisciplinary approaches. The ultimate goal is to integrate what we know about stem cells in different tissues to understand the extent to which they employ similar or different mechanisms to regulate critical functions. We have focused so far on the mechanisms that regulate stem cell self-renewal, aging, and their role in organogenesis.

Background/Aim. The heart has traditionally been considered as a static organ without capacity of regeneration after trauma. Currently, the more and more often asked question is whether the heart has any intrinsic capacities to regenerate myocytes after myocardial infarction. The aim of this study was to present the existence of the preserved muscle fibers in the myocardial scar following myocardial infarction as well as the presence of numerous cells of various size and form that differently reacted to the used immunohistochemical antibodies. Methods. Histological, histochemical and immunohistochemical analyses of myocardial sections taken from 177 patients who had died of acute myocardial infarction and had the myocardial scar following myocardial infarction, were carried out. More sections taken both from the site of acute infarction and scar were examined by the following methods: hematoxylin-eosin (HE), periodic acid schiff (PAS), PAS-diastasis, Masson trichrom, Malory, van Gieson, vimentin, desmin, myosin, myoglobin, alpha actin, smoth muscle actin (SMA), p53, leukocyte common antigen (LCA), proliferating cell nuclear antigen (PCNA), Ki-67, actin HHF35, CD34, CD31, CD45, CD45Ro, CD8, CD20. Results. In all sections taken from the scar region, larger or smaller islets of the preserved muscle fibers with the signs of hypertrophy were found. In the scar, a large number of cells of various size and form: spindle, oval, elongated with abundant cytoplasm, small with one nucleus and cells with scanty cytoplasm, were found. The present cells differently reacted to histochemical and immunohistochemical methods. Large oval cells showed negative reaction to lymphocytic and leukocytic markers, and positive to alpha actin, actin HHF35, Ki-67, myosin, myoglobin and desmin. Elongated cells were also positive to those markers. Small mononuclear cells showed positive reaction to lymphocytic markers. Endothelial and smooth muscle cells in the blood vessel walls were positive to CD34 and CD31, and smooth muscle cells to SMA. Oval and elongated cells were positive to PCNA and Ki-67. The preserved muscle fibers in the scar were positive to myosin, myoglobin and desmin as well as elongated and oval cells. Other cells were negative to these markers. Conclusion. Our findings speak that myocardial regeneration is maybe possible and develops in human ischemic heart damages and that the myocardium is not a static organ without capacity of cell regeneration.

Angiogenesis in solid tumors is important for tumor growth, invasion, and metastasis. However, angiogenesis plays also an important role in hematological malignancies. We have analyzed the expression of vascular endothelial growth factor (VEGF) in the leukemic blast cells and microvessel density (MVD) in the bone marrow biopsy samples of the patients with acute lymphoblastic leukemia (ALL). Bone marrow MVD of the patients with ALL was significantly higher compared with normal controls and complete remission (P0.001), but slightly lower than in patients with relapsed ALL (P0.05). The bone marrow blast VEGF expression was significantly higher in newly diagnosed ALL patients, with predominant strong VEGF expression as compared with complete remission patients (who had negative or weak VEGF expression) (P0.05), whereas initial values were slightly lower than in relapsed patients. There was a strong positive correlation between VEGF expression and MVD at presentation of ALL. Stronger expression of VEGF on blast cells indicates shorter overall survival in ALL. Furthermore, initial values of MVD had positive correlation with overall survival and leukemia-free survival (P=0.024 and P=0.017, respectively). Our data suggest that increased angiogenesis (confirmed by immunohistochemical expression of VEGF in leukemic blasts), and MVD may play an important role in the pathophysiology of ALL with prognostic implications. Thus, targeting VEGF pathway may bring the new approach for ALL treatment-using antiangiogenic drugs and tyrosine kinase inhibitors in combination with standard chemotherapy regimens.

Background/Aim. Ligation of a Toll-like receptor (TLR) by specific TLR agonists is a powerful tool for maturation induction of monocyte-derived dendritic cells (MoDCs). Studies so far have shown that the treatment of dendritic cells (DCs) with a TLR3 ligand, polyinosinic-polycytidylic acid [Poly(I:C)], may be an appropriate activation agent for obtaining mature MoDCs, competent to prime effective immune responses. However, little is known about how subsequent interaction of MoDCs with T cell-derived stimuli, such as CD40 or interferon-γ (IFN-γ), modulates MoDC functions. Therefore, this problem was the main objective of this study. Methods. Immature MoDCs were prepared by cultivation of monocytes from peripheral blood mononuclear cells with granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin (IL)-4 for 5 days. After that, maturation was induced by the treatment of these cells with Poly(I:C) for 2 days. At day 6, immature MoDCs and Poly(I:C)-activated MoDCs were incubated either with CD40 ligand (L)-transfected J558 cells or IFN-γ for additional 24 hours. Cytokine production was measured by ELISA and FlowCytomix Human T helper Th1/Th2 11plex. Allostimulatory capability of MoDCs was tested using an allogeneic mixed leukocyte reaction (MLR) assay. Results. Immature MoDCs showed a moderate potential for stimulation of proliferation of CD4+ T cells, which was enhanced by the treatment with Poly(I:C). Ligation of CD40 or treatment with IFN-γ of immature or Poly(I:C)-treated MoDCs significantly up-regulated their allostimulatory activity. MoDCs matured in the presence of Poly(I:C) up-regulated the production of IL- 12 and IL-10, which was followed by increased levels of IFN- γ and decreased levels of IL-5 in co-cultures with allogeneic CD4+ T cells. Ligation of CD40 on immature MoDCs upregulated the production of IL-12 and IL-23 which was accompanied by increased secretion of IFN-γ in co-culture. Stimulation of CD40 on Poly(I:C)-treated MoDCs significantly enhanced the production of IL-12, IL-23 and IL-10. However, such treated MoDCs decreased the production of IFN-γ and IL-10 and up-regulated the secretion of IL-17. Immature MoDCs treated with IFN-γ up-regulated IL-12, but lowered the production of IL-5 and IL-17 by CD4+ T cells. Treatment of Poly(I:C)-activated MoDCs with IFN-γ down-regulated the production of IL-12 and up-regulated IL- 10 by these cells and increased/decreased the levels of IL-10/ IFN-γ, respectively, in co-culture with CD4+ T cells. Conclusion. Treatment with Poly(I:C) or ligation of CD40 on immature MoDCs induces maturation of these cells into a phenotype that supports Th1 response. Activation of CD40 on Poly(I:C)-treated MoDCs shifts the immune response towards Th17. Treatment of immature MoDCs with IFN-γ down-regulated Th2 and Th17 responses. However, addition of IFN-γ to Poly(I:C)-activated MoDCs down-regulated Th1 response and promote T regulatory mechanisms. Each of these results may have functional and therapeutic implications.

Acetylsalicilyc acid (aspirin, ASA) is a well known anti-inflammatory drug with immunomodulatory properties. NO-releasing aspirins (NO-ASA) are new compounds with anti-inflammatory properties. We studied the effects of ASA and two NO-ASA (NCX 4016 and NCX 4040) on human monocyte-derived dendritic cells (MoDC). Immature MoDC were generated in vitro from monocytes in the presence of recombinant human granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin (IL)-4. Mature MoDC were obtained by adding lipopolysaccharide (LPS) in cultures of immature MoDC. As we found that ASA at 4-8 mM, NCX 4016 at 400-800 mu M and NCX 4040 at 4-8 mu M stimulated apoptosis of monocytes and immature MoDC, sub-apoptotic concentrations of ASA (2 mM), NCX 4016 (200 mu M) and NCX 4040 (2 mu M) were used in experiments. Examined substances were added at the beginning of MoDC cultivation. MoDC differentiated in the presence of examined compounds had lower expression of HLA-DR, CD80, CD40 and CD54, decreased allostimulatory activity and lower production of IL-12 p40. ASA and NCX 4016 decreased production of IL-10, whereas NCX 4040 had the opposite effect. ASA inhibited the expression of CD1a and prevented downregulation of 014, NCX 4016 stimulated the differentiation of CD1a(+)CD14(+) and CD1a(-)CD14(+) cells, whereas NCX 4040 decreased the proportion of CD1a(+)CD14(-) and increased the frequency of CD1a(+)CD14(+) cells, compared to control. Maturation, both in ASA and NO-ASA treated MoDC was characterized by decreased allostimulatory activity, lower expression of CD83, HLA-DR, costimulatory molecules and CD54 and decreased production of IL-10 and IL-12 p40. In conclusion, we confirmed that ASA impairs differentiation, maturation and function of MoDC and found that NCX 4016 and NCX 4040 exerted similar, but not identical effects at about 10- and 1000-fold lower concentrations, respectively, compared to ASA.

Introduction Hematopoiesis is a continuous, dynamic and highly complex process resulting in production of various mature blood cells from a small population of pluripotent stem and progenitor cells through diverse proliferative and differentiative events. Numerous studies have demonstrated that a complex network of interactive cytokines regulates the survival, maturation, and proliferation of hematopoietic stem and progenitor cells (HSPCs). Application of cell-mediated therapy Massive application of different cell-mediated therapeutic methods has resulted in an increased need for both specific HSPCs and operating procedures providing minimal cell damage during collection, processing and storage in a liquid or frozen state. Therefore, the basic aim of cell harvesting, selection, as well as cryopreservation is to minimize cell damage during these procedures. HSPCs are cells which exhibit extensive self-renewal and proliferative capacity, associated with the capacity to differentiate into all blood cells and other cell lineages (plasticity of HSPC). Thanks to these properties, stem cells can provide complete and permanent restoration of hematopoiesis, which is the basis for clinical employment of HSPC transplantation. In addition, totipotent stem cells can be used for the so called "cell-therapy" in different clinical settings (e.g. myocardial regeneration after acute infarction). Conclusion Despite the fact that HSPC transplantation is already in routine use, some questions related to the optimal blood progenitor/cell collection, selection, storage and clinical use are still unresolved. Therefore, this review only briefly discusses the therapeutic use of HSPCs in different clinical areas and focuses on the recommendations, as well as the specific transfusion policies related to HSPC collection, processing, and cryopreservation with an emphasis on quality control.

There is a need for improvement of the detection and treatment of the antibody-mediated graft rejection for ABO-incompatible kidney transplant recipients. With the development of novel pre-conditioning protocols, which employ anti-CD20 antibody, therapeutic plasma exchange plus extracorporeal immunoadsorption and standard immunosuppression application, together with the use of more sensitive and objective assays for immunological monitoring, patients that were not candidates for kidney transplant in the past, are now being transplanted. We have designed a pre-conditioning protocol for ABO-incompatible kidney transplants based on TPE plus our own simple "closed-circuit" immunoadsorption technique - combined by anti-CD20, standard immunosuppressive treatment, and without splenectomy. The results obtained in this study strongly support our hypothesis leading to the conclusion that this protocol can be used successfully, with high-quality ABO antibody depletion (p0.001) and beneficial clinical findings. The application of this protocol is safe, and not associated with alteration in normal plasma constituent levels or with occurrence of any side effects of apheresis or clinical consequences. Finally, this pre-conditioning protocol radically reduces the treatment-cost. Definitive conclusions can only be drawn from larger, randomized, controlled clinical trials.

To evaluate the clinical characteristics of splenic marginal-zone lymphoma (SMZL) following antigen expression and the influence of therapeutic approaches on clinical outcome and overall survival (OS).A total of 30 patients with typical histological and immunohistochemical SMZL patterns were examined. Splenectomy plus chemotherapy was applied in 20 patients, while splenectomy as a single treatment-option was performed in 10 patients. Prognostic factor and overall survival rate were analyzed.Complete remission (CR) was achieved in 20 (66.7%), partial remission (PR) in seven (23.3%), and lethal outcome due to disease progression occurred in three (10.0%) patients. Median survival of patients with a splenectomy was 93.0 mo and for patients with splenectomy plus chemotherapy it was 107.5 mo (Log rank = 0.056, P0.05). Time from onset of first symptoms to the beginning of the treatment (mean 9.4 mo) was influenced by spleen dimensions, as measured by computerized tomography and ultra-sound (t = 2.558, P = 0.018). Strong positivity (+++) of CD20 antigen expression in splenic tissue had a positive influence on OS (Log rank = 5.244, P0.05). The analysis of factors interfering with survival (by the Kaplan-Meier method) revealed that gender, general symptoms, clinical stage, and spleen infiltration type (nodular vs diffuse) had no significant (P0.05) effects on the OS. The expression of other antigens (immunohistochemistry) also had no effect on survival-rate, as measured by a c2 test (P0.05).Initial splenectomy combined with chemotherapy has been shown to be beneficial due to its advanced remission rate/duration; however, a larger controlled clinical study is required to confirm our findings.

AIM: To determine clinical characteristics and treatment outcome of gastric lymphoma after chemotherapy and immuno-chemotherapy. METHODS: Thirty four patients with primary gastric mucosa associated lymphoid tissue (MALT) lymphoma (Ann Arbor stages I to IV) were enrolled. All had upper gastric endoscopy, abdominal ultrasonography, CT and H pylori status assessment (histology and serology). After anti-H pylori treatment and initial chemotherapy, patients were re-examined every 4 mo. RESULTS: Histological regression of the lymphoma was complete in 22/34 (64.7%) and partial in 9 (26.5%) patients. Median follow up time for these 31 responders was 60 mo (range 48-120). No regression was noted in 3 patients. Among the 25 (73.5%) H pylori positive patients, the eradication rate was 100%. CONCLUSION: Using univariate analysis, predictive factors for overall survival were international prognostic index (IPI) score, hemoglobin level, erythrocyte sedimentation rate (ESR), and platelet numbers (P < 0.005). In addition to this, Cox proportion hazard model differentiate IPI score, ESR, and platelets as predictors of survival.

The influence of five different controlled- and noncontrolled-rate cryopreservation protocols combined with different DMSO concentrations was assessed on the recovery of frozen mouse bone marrow cells and human peripheral blood mononuclear cells (MNC). The recovery of murine primitive pluripotent hematopoietic stem cells (MRA and CFU-Sd12) and granulocyte-monocyte progenitors (CFU-GM) was investigated after thawing. The recovery and viability of human MNC, CFU-GM recovery, as well as the engraftment potential of thawed MNC evaluated through the reconstitution of hematopoiesis in patients treated with autologous HSPC transplantation were assessed. For murine cells, the most efficient cryopreservation protocol was the controlled-rate protocol designed to compensate for the release of fusion heat, which enable the best recovery of CFU-GM and CFU-Sd12 when combined with 5%DMSO concentration, while a better recovery of MRA was achieved with 10%DMSO. Controlled-rate cryopreservation protocol also enabled better recovery and viability of thawed human MNC. Although 5%DMSO also resulted in better human CFU-GM recovery, for autologous HSPC transplantation controlled-rate freezing in combination with 10%DMSO was used, having in mind that higher DMSO concentration enables better recovery of very primitive stem cells. The achieved rapid reconstitution of hematopoiesis in patients, on the day 11 th after transplantation, confirmed that this cryopreservation procedure was optimal for efficient cryopreservation of hematopoietic stem and progenitor cells used for transplantation.