Adipose-derived stem cell adhesion on laminin-coated microcarriers improves commitment toward the cardiomyogenic lineage

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NFL-lipid nanocapsules for brain neural stem cell targeting in vitro and in vivo

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MRI indices of functional recovery following intracerebral implantation of a human neural stem cell line in a pre-clinical model of ischaemic stroke

Stem cell therapy for ischaemic stroke is an emerging field in light of an increasing number of patients surviving with permanent disability. Several allogenic and autologous cells types are now in clinical trials with preliminary evidence of safety. Some clinical studies have reported functional improvements in some patients. After initial safety evaluation in a Phase 1 study, the conditionally immortalised human neural stem cell line CTX0E03 is currently in a Phase 2 clinical trial (PISCES-II). Previous pre-clinical studies conducted by ReNeuron Ltd, showed evidence of functional recovery in the Bilateral Asymmetry test up to 6 weeks following transplantation into rodent brain, 4 weeks after middle cerebral artery occlusion. Resting-state fMRI is increasingly used to investigate brain function in health and disease, and may also act as a predictor of recovery due to known network changes in the post-stroke recovery period. Resting-state methods have also been applied to non-human primates and rodents which have been found to have analogous resting-state networks to humans. The sensorimotor resting-state network of rodents is impaired following experimental focal ischaemia of the middle cerebral artery territory. However, the effects of stem cell implantation on brain functional networks has not previously been investigated. Prior studies assessed sensorimotor function following sub-cortical implantation of CTX0E03 cells in the rodent post-stroke brain but with no MRI assessments of functional improvements. This thesis presents research on the effect of sub-cortical implantation of CTX0E03 cells on the resting- state sensorimotor network and sensorimotor deficits in the rat following experimental stroke, using protocols based on previous work with this cell line. The work in this thesis identified functional tests of appropriate sensitivity for long-term dysfunction suitable for this laboratory, and investigated non-invasive monitoring of physiological variables required to optimize BOLD signal stability within a high-field MRI scanner. Following experimental stroke, rats demonstrated expected sensorimotor dysfunction and changes in the resting-state sensorimotor network. CTX0E03 cells did not improve post-stroke functional outcome (compared to previous studies) and with no changes in resting-state sensorimotor network activity. However, in control animals, we observed changes in functional networks due to the stereotaxic procedure. This illustrates the sensitivity of resting-state fMRI to stereotaxic procedures. We hypothesise that the damage caused by cell or vehicle implantation may have prevented functional and network recovery which has not been previously identified due to the application of different functional tests. The findings in this thesis represent one of few pre-clinical studies in resting-state fMRI network changes post-stroke and the only to date applying this technique to evaluate functional outcomes following a clinically applicable human neural stem cell treatment for ischaemic stroke. It was found that injury caused by stereotaxic injection should be taken into account when assessing the effectiveness of treatment.

Implantation of mouse embryonic stem cell-derived cardiac progenitor cells preserves function of infarcted murine hearts.

Stem cell transplantation holds great promise for the treatment of myocardial infarction injury. We recently described the embryonic stem cell-derived cardiac progenitor cells (CPCs) capable of differentiating into cardiomyocytes, vascular endothelium, and smooth muscle. In this study, we hypothesized that transplanted CPCs will preserve function of the infarcted heart by participating in both muscle replacement and neovascularization. Differentiated CPCs formed functional electromechanical junctions with cardiomyocytes in vitro and conducted action potentials over cm-scale distances. When transplanted into infarcted mouse hearts, CPCs engrafted long-term in the infarct zone and surrounding myocardium without causing teratomas or arrhythmias. The grafted cells differentiated into cross-striated cardiomyocytes forming gap junctions with the host cells, while also contributing to neovascularization. Serial echocardiography and pressure-volume catheterization demonstrated attenuated ventricular dilatation and preserved left ventricular fractional shortening, systolic and diastolic function. Our results demonstrate that CPCs can engraft, differentiate, and preserve the functional output of the infarcted heart.

Firepolished glass microtools for human embryonic stem cell (HESC) cultivation

Abstract not available

Functional polymorphism of the human arylamine N-acetyltransferase type 1 gene caused by (CT)-T-190 and G(560)A mutations

Human N-acetyltransferase type 1 (NAT1) catalyses the N- or O-acetylation of various arylamine and heterocyclic amine substrates and is able to bioactivate several known carcinogens. Despite wide inter-individual variability in activity, historically, NAT1 was considered to be monomorphic in nature. However, recent reports of allelic variation at the NAT1 locus suggest that it may be a polymorphically expressed enzyme. In the present study, peripheral blood mononuclear cell NAT1 activity in 85 individuals was found to be bimodally distributed with approximately 8% of the population being slow acetylators. Subsequent sequencing of the individuals having slow acetylator status showed all to have either a (CT)-T-190 or G(560)A base substitution located in the protein encoding region of the NAT1 gene. The (CT)-T-190 base substitution changed a highly conserved Arg(64), which others have shown to be essential for fully functional NAT1 protein. The (CT)-T-190 mutation has not been reported previously and we have named it NAT1*17. The G(560)A mutation is associated with the base substitutions previously observed in the NAT1*10 allele and this variant (NAT1*14) encodes for a protein with reduced acetylation capacity. A novel method using linear PCR and dideoxy terminators was developed for the detection of NAT1*14 and NAT1*17. Neither of these variants was found in the rapid acetylator population. We conclude that both the (CT)-T-190 (NAT1*17) and G(560)A (NAT1*14) NAT1 structural variants are involved in a distinct NAT1 polymorphism. Because NAT1 can bioactivate several carcinogens, this polymorphism may have implications for cancer risk in individual subjects. (C) 1998 Chapman & Hall Ltd.

Current Patient Management of Chronic Myeloid Leukemia in Latin America A Study by the Latin American Leukemia Net (LALNET)

BACKGROUND: Treatment recommendations have been developed for management of patients with chronic myeloid leukemia (CML). METHODS: A 30-item multiple-choice questionnaire was administered to 435 hematologists and oncohematologists in 16 Latin American countries. Physicians self-reported their diagnostic, therapeutic, and disease management strategies. RESULTS: Imatinib is available as initial therapy to 92% of physicians, and 42% of physicians have access to both second-generation tyrosine kinase inhibitors. Standard-dose imatinib is the preferred initial therapy for most patients, but 20% would manage a young patient initially with an allogeneic stem cell transplant from a sibling donor, and 10% would only offer hydroxyurea to an elderly patient. Seventy-two percent of responders perform routine cytogenetic analysis for monitoring patients on therapy, and 59% routinely use quantitative polymerase chain reaction. For patients who fail imatinib therapy, 61% would increase the dose of imatinib before considering change to a second-generation tyrosine kinase inhibitor, except for patients aged 60 years, for whom a switch to a second-generation tyrosine kinase inhibitor was the preferred choice. CONCLUSIONS: The answers to this survey provide insight into the management of patients with CML in Latin America. Some deviations from current recommendations were identified. Understanding the treatment patterns of patients with CML in broad population studies is important to identify needs and improve patient care. Cancer 2010;116:4991-5000. (C) 2070 American Cancer Society.

Genital Manifestation of Graft-vs.-Host Disease: A Series of Case Reports

Introduction. After hematopoietic stem cell transplantation (HSCT), many patients present genital graft-vs.-host disease (GVHD) that can culminate with sexual problems, which are poorly dimensioned. Aim. We hope to draw attention to the need to perform genital biopsy to diagnose genital GVHD, and thus to call attention to the need to incorporate careful attention to sexual health in the treatment of these patients. Methods. Five allogeneic stem cell transplant recipients complaining of coital pain after HSCT were clinically diagnosed for genital GVHD. Genital biopsies were given for histological analysis, and microphotographs of the corresponding marked field in the slide were taken. Specimens were evaluated by the site pathologist and then sent to a reference pathologist, each blinded to the histological findings. A literature search was performed in PubMed/MEDLINE (1966-2009) for cross-sectional and cohort studies or trials related to genital GVHD. Expert opinions peer reviews and case reports were also considered. Main Outcome Measures. HSCT, genital GVHD, genital biopsy. Results. The biopsy showed evidence of dilated apoptotic cells in the basal layer and detachment of the epithelial lining of the mucosa, hyalinization and thickening of collagen fibers, capillary ectasia, and mononuclear inflammatory infiltrate of the submucosa. Three patients presented vulval lesion such as leucoplasia and ulcer on the large lip. Histological analyses showed evidence of epithelial hyperplasia and influx of inflammatory cells to the epithelial surface, intercellular edema and spongiosis, apoptotic bodies on the basal layer of the epithelium, spongiosis, and nuclear vacuolization. A common treatment based on corticotherapy resulted in complete remission of coetaneous or mucous genital lesions in all five patients. Conclusion. Genital biopsy is important to differentially diagnose GVHD and secondary symptoms due to hypoestrogenism. Prevention is the most important step in controlling the evolution GVHD in the vagina to prevent vaginal obstruction and sexual dysfunction. da Silva Lara LA, de Andrade JM, Mauad LMQ, Ferrarese SR, Marana HRC, Tiezzi DG, and de Sa Rosa e Silva ACJ. Genital manifestation of graft-vs.-host disease: A series of case reports. J Sex Med 2010;7:3216-3225.

Effect of BCG stimulus on proinflammatory cytokine production in laryngeal cancer

Background Evaluate the production of TNF and IL-6 in the supernatant of peripheral blood mononuclear cell (PBMC) cultures of patients with supraglottic laryngeal cancer before and after surgical treatment. Materials and methods Adherent cell cultures were stimulated with LPS and BCG. Fourteen patients with advanced supraglottic laryngeal cancer were studied. Cytokine concentration was determined by ELISA in supernatants of mononuclear cell cultures. Results In non-stimulated cultures, lower TNF cytokine levels were detected during the late postoperative (LP) period compared to control (P = 0.02). LP TNF and IL-6 levels were high in cultures stimulated with LPS compared with the preoperative period (PREOP) (P = 0.007; P = 0.008, respectively). Stimulation with BCG led to increased levels of TNF and IL-6 during the LP period compared to control (P = 0.001; P = 0.04, respectively). Conclusions BCG is able to modulate the immune response of patients with advanced supraglottic laryngeal cancer in vitro, increasing the secretion of TNF and IL-6 by macrophages during the postoperative period.

Glucocorticoid resistance in dialysis patients may impair the kidney allograft outcome

This study examines in vitro steroid sensitivity in chronic renal failure ( CRF) patients and its influence on the allograft outcome. We determined the inhibitory effect of dexamethasone ( DEX) on concanavalin A ( Con-A)-stimulated peripheral blood mononuclear cell ( PBMC) proliferation, and glucocorticoid receptor` ( GR) number of binding sites ( B-max) and affinity ( K-d) in 28 CRF patients and 40 normal healthy controls. Based on K-d values > 95th percentile from controls, patients were divided into two groups: glucocorticoid resistant ( n = 11) and glucocorticoid sensitive ( n = 17). Patients were followed during 18 months post-transplantation observing acute rejection episodes ( ARE), chronic allograft nephropathy ( CAN), allograft failure and death. The DEX concentration that caused 50% inhibition of Con-A-stimulated PBMC proliferation ( IC50) was higher in CRF than in healthy controls ( 2.2 x 10(-5) +/- 1.0 x 10(-5) versus 8.3 x 10(-6) +/- 4.2 x 10(-6) mol/ L, P = 0.02). Values of Kd ( 12.4 +/- 1.8 versus 7.2 +/- 0.9 nM) and Bmax ( 7.7 +/- 1.1 versus 4.1 +/- 0.3 fmol/ mg protein) were higher in CRF patients ( P = 0.02 and P = 0.001, respectively). There were higher incidences of ARE ( P = 0.02) and CAN ( P = 0.002) in the glucocorticoid-resistant group. Univariate and multivariate logistic regression showed that Kd was an independent predictor of ARE ( OR 8.8, P= 0.03) aswell as of CAN ( OR 16.5, P= 0.01). In conclusion, we observed glucocorticoid resistance in a subgroup of CRF patients undergoing dialysis, which led to a higher morbidity due to ARE and CAN in an 18-month follow-up period.

Accumulation of human heat shock protein 60-reactive T cells in the gingival tissues of periodontitis patients

Heat shock protein 60s (hsp60) are remarkably immunogenic, and both T-cell and antibody responses to hsp60 have been reported in various inflammatory conditions. To clarify the role of hsp60 in T-cell responses in periodontitis, we examined the proliferative response of peripheral blood mononuclear cells (PBMC), as well as the cytokine profile and T-cell clonality, for periodontitis patients and controls following stimulation with recombinant human hsp60 and Porphyromonas gingivalis GroEL. To confirm the infiltration of hsp60-reactive T-cell clones into periodontitis lesions, nucleotide sequences within complementarity-determining region 3 of the T-cell receptor (TCR) beta-chain were compared between hsp60-reactive peripheral blood T cells and periodontitis lesion-infiltrating T cells. Periodontitis patients demonstrated significantly higher proliferative responses of PBMC to human hsp60, but not to P. gingivalis GroEL, than control subjects. The response was inhibited by anti-major histocompatibility complex class 11 antibodies. Analysis of the nucleotide sequences of the TCR demonstrated that human hsp60-reactive T-cell clones and periodontitis lesion-infiltrating T cells have the same receptors, suggesting that hsp60-reactive T cells accumulate in periodontitis lesions. Analysis of the cytokine profile demonstrated that hsp60-reactive PBMC produced significant levels of gamma interferon (IFN-gamma) in periodontitis patients, whereas P. gingivalis GroEL did not induce any, skewing toward a type1 or type2 cytokine profile. In control subjects no significant expression of IFN-gamma or interleukin 4 was induced. These results suggest that periodontitis patients have human hsp60-reactive T cells with a type I cytokine profile in their peripheral blood T-cell pools.

Regulatory Cells, Cytokine Pattern and Clinical Risk Factors for Asthma in Infants and Young Children with Recurrent Wheeze

Several risk factors for asthma have been identified in infants and young children with recurrent wheeze. However, published literature has reported contradictory findings regarding the underlying immunological mechanisms. OBJECTIVES: This study was designed to assess and compare the immunological status during the first 2 years in steroid-naive young children with >or= three episodes of physician-confirmed wheeze (n=50), with and without clinical risk factors for developing subsequent asthma (i.e. parental asthma or a personal history of eczema and/or two of the following: wheezing without colds, a personal history of allergic rhinitis and peripheral blood eosinophilia >4%), with age-matched healthy controls (n=30). METHODS: Peripheral blood CD4(+)CD25(+) and CD4(+)CD25(high) T cells and their cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), GITR and Foxp3 expression were analysed by flow cytometry. Cytokine (IFN-gamma, TGF-beta and IL-10), CTLA-4 and Foxp3 mRNA expression were evaluated (real-time PCR) after peripheral blood mononuclear cell stimulation with phorbol 12-myristate 13-acetate (PMA) (24 h) and house dust mite (HDM) extracts (7th day). RESULTS: Flow cytometry results showed a significant reduction in the absolute number of CD4(+)CD25(high) and the absolute and percentage numbers of CD4(+)CD25(+)CTLA-4(+) in wheezy children compared with healthy controls. Wheezy children at a high risk of developing asthma had a significantly lower absolute number of CD4(+)CD25(+) (P=0.01) and CD4(+)CD25(high) (P=0.04), compared with those at a low risk. After PMA stimulation, CTLA-4 (P=0.03) and Foxp3 (P=0.02) expression was diminished in wheezy children compared with the healthy children. After HDM stimulation, CTLA-4 (P=0.03) and IFN-gamma (P=0.04) expression was diminished in wheezy children compared with healthy children. High-risk children had lower expression of IFN-gamma (P=0.03) compared with low-risk and healthy children and lower expression of CTLA-4 (P=0.01) compared with healthy children. CONCLUSIONS: Although our findings suggest that some immunological parameters are impaired in children with recurrent wheeze, particularly with a high risk for asthma, further studies are needed in order to assess their potential as surrogate predictor factors for asthma in early life.

Identification of Human T-lymphotropic Virus Type I (HTLV-I) Subtypes Using Restrited Fragment Length Polymorphism in a Cohort of Asymptomatic Carriers and Patients with HTLV-I-associated Myelopathy/tropical Spastic Paraparesis from São Paulo, Brazil

Although human T-lymphotropic virus type I (HTLV-I) exhibits high genetic stability, as compared to other RNA viruses and particularly to human immunodeficiency virus (HIV), genotypic subtypes of this human retrovirus have been characterized in isolates from diverse geographical areas. These are currently believed not to be associated with different pathogenetic outcomes of infection. The present study aimed at characterizing genotypic subtypes of viral isolates from 70 HTLV-I-infected individuals from São Paulo, Brazil, including 42 asymptomatic carriers and 28 patients with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), using restricted fragment length polymorphism (RFLP) analysis of long terminal repeat (LTR) HTLV-I proviral DNA sequences. Peripheral blood mononuclear cell lysates were amplified by nested polymerase chain reaction (PCR) and amplicons submitted to enzymatic digestion using a panel of endonucleases. Among HTLV-I asymptomatic carriers, viral cosmopolitan subtypes A, B, C and E were identified in 73.8%, 7.1%, 7.1% and 12% of tested samples, respectively, whereas among HAM/TSP patients, cosmopolitan A (89.3%), cosmopolitan C (7.1%) and cosmopolitan E (3.6%) subtypes were detected. HTLV-I subtypes were not statistically significant associated with patients' clinical status. We also conclude that RFLP analysis is a suitable tool for descriptive studies on the molecular epidemiology of HTLV-I infections in our environment.