Publications by authors named "Angelica Garcia-Perez"

The complex neuromuscular network that controls body movements is the target of severe diseases that result in paralysis and death. Here, we report the development of a robust and efficient self-organizing neuromuscular junction (soNMJ) model from human pluripotent stem cells that can be maintained long-term in simple adherent conditions. The timely application of specific patterning signals instructs the simultaneous development and differentiation of position-specific brachial spinal neurons, skeletal muscles, and terminal Schwann cells.

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Conditional transgene expression in human stem cells has been difficult to achieve due to the low efficiency of existing delivery methods, the strong silencing of the transgenes and the toxicity of the regulators. Most of the existing technologies are based on stem cells clones expressing appropriate levels of tTA or rtTA transactivators (based on the TetR-VP16 chimeras). In the present study, we aim the generation of Tet-On all-in-one lentiviral vectors (LVs) that tightly regulate transgene expression in human stem cells using the original TetR repressor.

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Mesenchymal stromal cells (MSCs) represent a promising tool for therapy in regenerative medicine, transplantation, and autoimmune disease due to their trophic and immunomodulatory activities. However, we are still far from understanding the mechanisms of action of MSCs in these processes. Transforming growth factor (TGF)-β1 is a pleiotropic cytokine involved in MSC migration, differentiation, and immunomodulation.

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Administration of in vitro expanded mesenchymal stromal cells (MSCs) represents a promising therapy for regenerative medicine and autoimmunity. Both mouse and human MSCs ameliorate autoimmune disease in syn-, allo- and xenogeneic settings. However, MSC preparations are heterogeneous which impairs their therapeutic efficacy and endorses variability between experiments.

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Nicotinamide, a soluble compound of the vitamin B3 group, has antimicrobial activity against several microorganisms ranging from viruses to parasite protozoans. However, the mode of action of this antimicrobial activity is unknown. Here, we investigate the trypanocidal activity of nicotinamide on Trypanosoma brucei, the causative agent of African trypanosomiasis.

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Regulation of RNA polymerase II transcription initiation is apparently absent in trypanosomes. Instead, these eukaryotes control gene expression mainly at the post-transcriptional level. Regulation is exerted through the action of numerous RNA-binding proteins that modulate mRNA processing, turnover, translation and localization.

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Multiple sclerosis (MS) is a severe debilitating disorder characterized by progressive demyelination and axonal damage of the central nervous system (CNS). Current therapies for MS inhibit the immune response and demonstrate reasonable benefits if applied during the early phase of relapsing–remitting MS (RRMS) while there are no treatments for patients that progress neither to the chronic phase nor for the primary progressive form of the disease. In this manuscript, we have studied the therapeutic efficacy of a cell and gene therapy strategy for the treatment of a mouse model of chronic MS [myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE)].

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Background And Aims: Many patients with complete spinal cord injury (SCI) exhibit demyelinated and poorly myelinated nerve fibers traversing the lesion site. Conventional doses of 4-aminopyridine (4-AP, 30 mg/day) have shown to provide no or minor functional improvement in these patients. We undertook this study to test the functional effect of high doses of 4-AP on patients with chronic complete SCI with cord continuity at the site of injury demonstrated by magnetic resonance imaging.

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Exosome vesicles of endocytic origin are involved in communication between tumor and immune cells. In addition, membrane rafts (MR) may support the sorting of proteins associated with exosomes. CD38 is found at the plasma membrane and in recycling endosomes, which are both redistributed toward the immunological synapse (IS) upon T cell antigen receptor (TCR) engagement.

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During immunologic synapse (IS) formation, human CD38 redistributes to the contact area of T cell-antigen-presenting cell (APC) conjugates in an antigen-dependent manner. Confocal microscopy showed that CD38 preferentially accumulated along the contact zone, whereas CD3-zeta redistributed toward the central zone of the IS. APC conjugates with human T cells or B cells transiently expressing CD38-green fluorescent protein revealed the presence of 2 distinct pools of CD38, one localized at the cell membrane and the other in recycling endosomes.

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