Background Optic-nerve injury results in impaired transmission of visual signals to central targets and leads to the death of retinal ganglion cells (RGCs) and irreversible vision loss. Therapies with mesenchymal stem cells (MSCs) from different sources have been used experimentally to increase survival and regeneration of RGCs. Methods We investigated the efficacy of human umbilical Wharton’s jelly-derived MSCs (hWJ-MSCs) and their extracellular vesicles (EVs) in a rat model of optic nerve crush. Results hWJ-MSCs had a sustained neuroprotective effect on RGCs for 14, 60, and 120 days after optic nerve crush. The same effect was obtained using serum-deprived hWJ-MSCs, whereas transplantation of EVs obtained from those cells was ineffective. Treatment with hWJ-MSCs also promoted axonal regeneration along the optic nerve and reinnervation of visual targets 120 days after crush. Conclusions The observations showed that this treatment with human-derived MSCs promoted sustained neuroprotection and regeneration of RGCs after optic nerve injury. These findings highlight the possibility to use cell therapy to preserve neurons and to promote axon regeneration, using a reliable source of human MSCs.

In the complex process of bone formation at the implant-tissue interface, surface properties are relevant factors modulating osteoblastic function. In this study, commercially pure titanium (cp Ti) samples were prepared with different surface characteristics using chemical attack with a sulfuric acid/hydrochloric acid based solution (treatment A); chemical attack plus anodic oxidation using phosphoric acid (treatment B); and chemical attack plus thermal oxidation followed by immersion in a sodium fluoride solution (treatment C). The samples were characterized by scanning electron microscopy (SEM), contact profilometry and contact angle. The biological performance of the prepared surfaces was evaluated using mice osteoblastic cell cultures for up to 21 days. Cells seeded on the different titanium samples showed similar behavior during cell attachment and spreading. However, cellular proliferation and differentiation were higher for samples submitted to treatments A and C (p < or = 0.05; n = 3), which were less rough and showed surface free energy with smaller polar components.

The P2X7 receptor is a critical purinergic receptor in immune cells. Its activation was associated with cathepsin release into macrophage cytosol, suggesting its involvement in lysosomal membrane permeabilization (LMP) and leakage. Nevertheless, the mechanisms by which P2X7 receptor activation induces LMP and leakage are unclear. This study investigated cellular mechanisms associated with endosomal and lysosomal leakage triggered by P2X7 receptor activation. We found that ATP at 500 μM and 5 mM (but not 50 μM) induced LMP in non-stimulated peritoneal macrophages. This effect was not observed in P2X7-deficient or A740003-pretreated macrophages. We found that the P2X7 receptor and pannexin-1 channels mediate calcium influx that might be important for activating specific ion channels (TRPM2 and two-pore channels) on the membranes of late endosomes and lysosomes leading to LMP leakage and consequent cathepsin release. These findings suggest the critical role of the P2X7 receptor in inflammatory and infectious diseases via lysosomal dysfunction.

Gangliosides are glycosphingolipids abundantly expressed in the vertebrate nervous system, and are classified into a‐, b‐, or c‐series according to the number of sialic acid residues. The enzyme GD3 synthase converts GM3 (an a‐series ganglioside) into GD3, a b‐series ganglioside highly expressed in the developing and adult retina. The present study evaluated the visual system of GD3 synthase knockout mice (GD3s–/–), morphologically and functionally. The absence of b‐ series gangliosides in the retinas of knockout animals was confirmed by mass spectrometry imaging, which also indicated an accumulation of a‐series gangliosides, such as GM3. Retinal ganglion cell (RGC) density was significantly reduced in GD3s–/– mice, with a similar reduction in the number of axons in the optic nerve. Knockout animals also showed a 15% reduction in the number of photoreceptor nuclei, but no difference in the bipolar cells. The area occupied by GFAP‐positive glial cells was smaller in GD3s–/– retinas, but the number of microglial cells/macrophages did not change. In addition to the morphological alterations, a 30% reduction in light responsiveness was detected through quantification of pS6‐expressing RGC, an indicator of neural activity. Furthermore, electroretinography (ERG) indicated a significant reduction in RGC and photoreceptor electrical activity in GD3s–/– mice, as indicated by scotopic ERG and pattern ERG (PERG) amplitudes. Finally, evaluation of the optomotor response demonstrated that GD3s–/– mice have reduced visual acuity and contrast sensitivity. These results suggest that b‐series gangliosides play a critical role in regulating the structure and function of the mouse visual system.

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In the article titled "Preconditioning of Rat Bone Marrow-Derived Mesenchymal Stromal Cells with Toll-Like Receptor Agonists" [1], there was an error in the production of Figure 2(b) which resulted in some colouration being lost. The publisher apologises for introducing this error, and the corrected figure is shown below and is listed as Figure 1:

Congenital toxoplasmosis constitutes a major cause of pre- and post-natal complications. Fetal infection with Toxoplasma gondii influences development and can lead to microcephaly, encephalitis, and neurological abnormalities. Few studies have attempted to explain the impact of T. gondii infection on the physiology of mature nerve cells, and no systematic study concerning the effect of infection of neural progenitor cells by T. gondii in the biology of these progenitors is available. We infected cortical intermediate progenitor cell cultivated as neurospheres obtained from E16.5 Swiss Webster mice with T. gondii (Me49 strain) tachyzoites to mimic the developing mouse cerebral cortex in vitro. Infection decreased cell proliferation as detected by Ki67 staining at 48 and 72 hours post infection (hpi) in floating neurospheres, resulting in reduced cellularity at 96 hpi. Neurogenic and gliogenic potential, assessed in plated neurospheres, was shown to be impaired in infected cultures, as indicated by neurofilament heavy chain (NF-200) and GFAP staining, respectively. To further investigate the impact of infection on neuronal differentiation, Neuro2a neuroblasts were infected and after 24 hpi, neurogenic differentiation was induced with serum withdrawal. We confirmed that infection induces a decrease in neuroblast-neuron differentiation rates in cells stained for NF-200, with reduced neuritogenesis. Migration rates were analyzed in plated neurospheres. At 120 h after plating, infected cultures exhibited decreased overall migration rates and altered the radial migration of nestin-, GFAP- and NF-200-positive cells. These findings indicate that T. gondii infection of neural progenitor cells may lead to reduced neuro/gliogenesis due to an imbalance in cell proliferation alongside an altered migratory profile. If translated to the in vivo situation, these data could explain, in part, the cortical malformations observed in congenitally infected individuals.