Urine-derived stem/progenitor cells: A focus on their characterization and potential

Cell therapy, i.e., the use of cells to repair an affected tissue or organ, is at the forefront of regenerative and personalized medicine. Among the multiple cell types that have been used for this purpose [including adult stem cells such as mesenchymal stem cells or pluripotent stem cells], urine-derived stem cells (USCs) have aroused interest in the past years. USCs display classical features of mesenchymal stem cells such as differentiation capacity and immunomodulation. Importantly, they have the main advantage of being isolable from one sample of voided urine with a cheap and unpainful procedure, which is broadly applicable, whereas most adult stem cell types require invasive procedure. Moreover, USCs can be differentiated into renal cell types. This is of high interest for renal cell therapy-based regenerative approaches. This review will firstly describe the isolation and characterization of USCs. We will specifically present USC phenotype, which is not an object of consensus in the literature, as well as detail their differentiation capacity. In the second part of this review, we will present and discuss the main applications of USCs. These include use as a substrate to generate human induced pluripotent stem cells, but we will deeply focus on the use of USCs for cell therapy approaches with a detailed analysis depending on the targeted organ or system. Importantly, we will also focus on the applications that rely on the use of USC-derived products such as microvesicles including exosomes, which is a strategy being increasingly employed. In the last section, we will discuss the remaining barriers and challenges in the field of USC-based regenerative medicine.     

Wnt4 participates in the formation of vertebrate neuromuscular junction

Neuromuscular junction (NMJ) formation requires the highly coordinated communication of several reciprocal signaling processes between motoneurons and their muscle targets. Identification of the early, spatially restricted cues in target recognition at the NMJ is still poorly documented, especially in mammals. Wnt signaling is one of the key pathways regulating synaptic connectivity. Here, we report that Wnt4 contributes to the formation of vertebrate NMJ in vivo. Results from a microarray screen and quantitative RT-PCR demonstrate that Wnt4 expression is regulated during muscle cell differentiation in vitro and muscle development in vivo, being highly expressed when the first synaptic contacts are formed and subsequently downregulated. Analysis of the mouse Wnt4−/− NMJ phenotype reveals profound innervation defects including motor axons overgrowing and bypassing AChR aggregates with 30% of AChR clusters being unapposed by nerve terminals. In addition, loss of Wnt4 function results in a 35% decrease of the number of prepatterned AChR clusters while Wnt4 overexpression in cultured myotubes increases the number of AChR clusters demonstrating that Wnt4 directly affects postsynaptic differentiation. In contrast, muscle structure and the localization of several synaptic proteins including acetylcholinesterase, MuSK and rapsyn are not perturbed in the Wnt4 mutant. Finally, we identify MuSK as a Wnt4 receptor. Wnt4 not only interacts with MuSK ectodomain but also mediates MuSK activation. Taken together our data reveal a new role for Wnt4 in mammalian NMJ formation that could be mediated by MuSK, a key receptor in synaptogenesis.     

Neurofascin is a glial receptor for the paranodin/Caspr-contactin axonal complex at the axoglial junction

In myelinated fibers of the vertebrate nervous system, glial-ensheathing cells interact with axons at specialized adhesive junctions, the paranodal septate-like junctions. The axonal proteins paranodin/Caspr and contactin form a cis complex in the axolemma at the axoglial adhesion zone, and both are required to stabilize the junction. There has been intense speculation that an oligodendroglial isoform of the cell adhesion molecule neurofascin, NF155, expressed at the paranodal loop might be the glial receptor for the paranodin/Caspr-contactin complex, particularly since paranodin/Caspr and NF155 colocalize to ectopic sites in the CNS of the dysmyelinated mouse Shiverer mutant. We report that the extracellular domain of NF155 binds specifically to transfected cells expressing the paranodin/Caspr-contactin complex at the cell surface. This region of NF155 also binds the paranodin/Caspr-contactin complex from brain lysates in vitro. In support of the functional significance of this interaction, NF155 antibodies and the extracellular domain of NF155 inhibit myelination in myelinating cocultures, presumably by blocking the adhesive relationship between the axon and glial cell. These results demonstrate that the paranodin/Caspr-contactin complex interacts biochemically with NF155 and that this interaction is likely to be biologically relevant at the axoglial junction.     

Non-contiguous finished genome sequence and description of Anaerococcus vaginalis

We report the properties of a draft genome sequence of the bacterium Anaerococcus vaginalis strain PH9, a species within the Anaerococcus genus. This strain, whose genome is described here, was isolated from the fecal flora of a 26-year-old woman suffering from morbid obesity. A. vaginalis is an obligate anaerobic coccus. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 2,048,125-bp long (one chromosome but no plasmid) and contains 2,095 protein-coding and 38 RNA genes, including three rRNA genes.Key words: Anaerococcus vaginalis, genome     

Specification of GnRH-1 neurons by antagonistic FGF and retinoic acid signaling

A small population of neuroendocrine cells in the rostral hypothalamus and basal forebrain is the key regulator of vertebrate reproduction. They secrete gonadotropin-releasing hormone (GnRH-1), communicate with many areas of the brain and integrate multiple inputs to control gonad maturation, puberty and sexual behavior. In humans, disruption of the GnRH-1 system leads to hypogonadotropic gonadism and Kallmann syndrome. Unlike other neurons in the central nervous system, GnRH-1 neurons arise in the periphery, however their embryonic origin is controversial, and the molecular mechanisms that control their initial specification are not clear. Here, we provide evidence that in chick GnRH-1 neurons originate in the olfactory placode, where they are specified shortly after olfactory sensory neurons. FGF signaling is required and sufficient to induce GnRH-1 neurons, while retinoic acid represses their formation. Both pathways regulate and antagonize each other and our results suggest that the timing of signaling is critical for normal GnRH-1 neuron formation. While Kallmann's syndrome has generally been attributed to a failure of GnRH-1 neuron migration due to impaired FGF signaling, our findings suggest that in at least some Kallmann patients these neurons may never be specified. In addition, this study highlights the intimate embryonic relationship between GnRH-1 neurons and their targets and modulators in the adult.     

Selenoprotein N is dynamically expressed during mouse development and detected early in muscle precursors

Background  

In humans, mutations in the SEPN1 gene, encoding selenoprotein N (SelN), are involved in early onset recessive neuromuscular disorders, referred to as SEPN1-related-myopathies. The mechanisms behind these pathologies are poorly understood since the function of SelN remains elusive. However, previous results obtained in humans and more recently in zebrafish pointed to a potential role for SelN during embryogenesis. Using qRT-PCR, Western blot and whole mount in situ hybridization, we characterized in detail the spatio-temporal expression pattern of the murine Sepn1 gene during development, focusing particularly on skeletal muscles.     

Disease survey of free-ranging grey brocket deer (Mazama gouazoubira) in the Gran Chaco, Bolivia

Samples from 17 free-ranging hunter-killed grey brocket deer (Mazama gouazoubira) in the Gran Chaco, Bolivia, were collected during June-August 1999. All 17 deer appeared to be in good condition at the time of death. Gross necropsies were performed, serum was collected for serologic evaluation of selected infectious disease agents, and feces and ectoparasites were collected for evaluation of internal and external parasites. Serologic tests were positive for antibodies against bovine respiratory syncytial virus and four Leptospira interrogans serovars, with questionable results for epizootic hemorrhagic disease virus serotypes 1 and 2. No antibodies were detected to Anaplasma marginale, Babesia bigemina, Babesia bovis, Babesia odocoilei, bluetongue virus (serotypes 2, 10, 11, 13, and 17), bovine viral diarrhea virus, Brucella abortus, foot-and-mouth disease virus, infectious bovine rhinotracheitis virus, Mycobacterium avium subsp. paratuberculosis, and parainfluenza-3 virus. Sixty-four percent (7/11) of the deer had endoparasites. Amblyomma spp. ticks were found on seven deer, flies of the family Hippoboscidae on six deer, and lice on six deer.     

Plasmid-associated genes in the model micro-symbiont Sinorhizobium meliloti 1021 affect the growth and development of young rice seedlings

Sinorhizobium meliloti strain 1021 and its closely related strain Rm2011 inhibit rice seedling (Oryza sativa L. cv. Pelde) growth and development under certain rice-growing conditions. Experiments showed that inoculation of seedlings with approximately less than 10 cells of 1021 was sufficient to cause this inhibition. By using a series of plasmid-cured and plasmid-deleted derivatives of Rm2011, it was found that interactions between genes encoded on pSymA, and possibly pSymB, of Rm2011, affected rice growth and development by affecting both/either the plant and/or the bacteria. Further studies found that genes potentially related to indole-3-acetic acid (IAA) synthesis and nitrate metabolism, encoded on pSymA, were involved in rice growth inhibition in Sm1021- and Sm2011-treated rice seedlings. We conclude that the rice growth inhibition by S. meliloti Sm1021 is pSymA-associated and is induced by environmental nitrate.