22 research outputs found
Development of broad-spectrum human monoclonal antibodies for rabies post-exposure prophylaxis
Currently available rabies post-exposure prophylaxis (PEP) for use in humans includes equine or human rabies immunoglobulins (RIG). The replacement of RIG with an equally or more potent and safer product is strongly encouraged due to the high costs and limited availability of existing RIG. In this study, we identified two broadly neutralizing human monoclonal antibodies that represent a valid and affordable alternative to RIG in rabies PEP. Memory B cells from four selected vaccinated donors were immortalized and monoclonal antibodies were tested for neutralizing activity and epitope specificity. Two antibodies, identified as RVC20 and RVC58 (binding to antigenic site I and III, respectively), were selected for their potency and broad-spectrum reactivity. In vitro, RVC20 and RVC58 were able to neutralize all 35 rabies virus (RABV) and 25 non-RABV lyssaviruses. They showed higher potency and breath compared to antibodies under clinical development (namely CR57, CR4098, and RAB1) and commercially available human RIG. In vivo, the RVC20-RVC58 cocktail protected Syrian hamsters from a lethal RABV challenge and did not affect the endogenous hamster post-vaccination antibody response
Transplantation of clinical-grade human neural stem cells reduces neuroinflammation, prolongs survival and delays disease progression in the SOD1 rats.
Abstract Stem cells are emerging as a therapeutic option for incurable diseases, such as Amyotrophic Lateral Sclerosis (ALS). However, critical issues are related to their origin as well as to the need to deepen our knowledge of the therapeutic actions exerted by these cells. Here, we investigate the therapeutic potential of clinical-grade human neural stem cells (hNSCs) that have been successfully used in a recently concluded phase I clinical trial for ALS patients (NCT01640067). The hNSCs were transplanted bilaterally into the anterior horns of the lumbar spinal cord (four grafts each, segments L3–L4) of superoxide dismutase 1 G93A transgenic rats (SOD1 rats) at the symptomatic stage. Controls included untreated SOD1 rats (CTRL) and those treated with HBSS (HBSS). Motor symptoms and histological hallmarks of the disease were evaluated at three progressive time points: 15 and 40 days after transplant (DAT), and end stage. Animals were treated by transient immunosuppression (for 15 days, starting at time of transplantation). Under these conditions, hNSCs integrated extensively within the cord, differentiated into neural phenotypes and migrated rostro-caudally, up to 3.77 ± 0.63 cm from the injection site. The transplanted cells delayed decreases in body weight and deterioration of motor performance in the SOD1 rats. At 40DAT, the anterior horns at L3–L4 revealed a higher density of motoneurons and fewer activated astroglial and microglial cells. Accordingly, the overall survival of transplanted rats was significantly enhanced with no rejection of hNSCs observed. We demonstrated that the beneficial effects observed after stem cell transplantation arises from multiple events that counteract several aspects of the disease, a crucial feature for multifactorial diseases, such as ALS. The combination of therapeutic approaches that target different pathogenic mechanisms of the disorder, including pharmacology, molecular therapy and cell transplantation, will increase the chances of a clinically successful therapy for ALS
Biodiversity mainstreaming for healthy & sustainable food systems: A toolkit to support incorporating biodiversity into policies and programmes
The Biodiversity for Food and Nutrition Initiative (BFN Project) uses indigenous food biodiversity as a lens to address malnutrition, farmer livelihood resilience, and sustainability. Since 2012, the initiative has pioneered a cross-sectoral, partner-based approach to document and share information on 195 nutrient-rich, locally-adapted species ranging from African leafy vegetables to Amazonian fruits. Spearheaded by governments and research organizations in Brazil, Kenya, Sri Lanka, and Turkey, BFN developed a three-pronged methodology to ensure the conservation, revival, and promotion of these underutilised species.
This toolkit is an open-access guide to mainstreaming biodiversity that draws on case studies across the four partner countries, outlining steps to 1) Provide Evidence; 2) Influence Policy, and 3) Raise Awareness. With an emphasis on both key focus areas and site-specific examples, the toolkit offers readers inspiration to adapt the work of BFN to other regions. Links to key resources collect additional information and contextualise the project methods, for example, in relation to the FAO Voluntary Guidelines for Mainstreaming Biodiversity into Policies, Programmes and National and Regional Plans on Nutrition. Focus points within the toolkit include how to make use of: National Biodiversity Strategy and Action Plans, school feeding and procurement, green employment, cultural festivals, and business cases for mainstreaming biodiversity
Solitary waves in the Nonlinear Dirac Equation
In the present work, we consider the existence, stability, and dynamics of
solitary waves in the nonlinear Dirac equation. We start by introducing the
Soler model of self-interacting spinors, and discuss its localized waveforms in
one, two, and three spatial dimensions and the equations they satisfy. We
present the associated explicit solutions in one dimension and numerically
obtain their analogues in higher dimensions. The stability is subsequently
discussed from a theoretical perspective and then complemented with numerical
computations. Finally, the dynamics of the solutions is explored and compared
to its non-relativistic analogue, which is the nonlinear Schr{\"o}dinger
equation. A few special topics are also explored, including the discrete
variant of the nonlinear Dirac equation and its solitary wave properties, as
well as the PT-symmetric variant of the model
Toxoplasma gondii in wild boar and roe deer in Northern Italy : serosurvey and PCR-RFLP
Toxoplasma gondii infects all warm-blooded animals; in Europe several studies carried out in wildlife show seropositivity towards this parasite, in particular in wild ungulates.
In Northern Italy in the last years the culling of wild boar and roe deer is significantly increased and then the game meat consumption. As eating of raw or undercooked meat is a risk factor for Toxoplasmosis transmission to humans, we performed a serosurvey for this protozoan and its research in the muscular tissue.
The samples were collected during the 2008 and2009 hunting seasons; wild boar sera were tested by IFIT (Toxo-spot \uaeIF, bio-Meriaux) while roe deer by a commercial Elisa kit (ID Screen\uae Toxoplasmosis Indirect ELISA, IDVET, Montpellier, France); we analysed respectively 281 and 505 sera:. 63 wild boar (22.4%, I.C. 95% 17.77-27.84) and 110 roe deer sera were positive (21.78%, I.C. 95% 18.31-25.69).
We further examined the muscular tissues of the seropositive animals for directly detecting the parasite by a PCR-RFLP assay targeting the 18S small-subunit ribosomal gene of T. gondii. The PCR was carried out on samples of muscular tissue (heart, diaphragm and masseter) of 53 seropositive wild boar and from 49 hearts of seropositive roe deer. All the samples tested negative. By the restriction enzyme analysis of the amplified products we detected positive samples for Sarcocystis spp., that by sequencing analysis has been identified as S. miescheriana in wild boar and as S. cruzi and S. gracilis in roe deer. Although we couldn\u2019t detect the parasite in muscular tissue, the serological results show a remarkable exposure to T. gondii in both host species and recommend a correct information and public health implication, also considering that consumption of undercooked or cured game is a widespread habit
Rabies vaccination: Higher failure rates in imported dogs than in those vaccinated in Italy
The current European Union (EU) legislation decrees that pets entering the EU from a rabies-infected third country have to obtain a satisfactory virus-neutralizing antibody level, while those moving within the EU require only rabies vaccination as the risk of moving a rabid pet within the EU is considered negligible. A number of factors driving individual variations in dog vaccine response have been previously reported, including a high rate of vaccine failure in puppies, especially those subject to commercial transport. A total of 21 001 observations collected from dogs (2006–2012) vaccinated in compliance with the current EU regulations were statistically analysed to assess the effect of different risk factors related to rabies vaccine efficacy. Within this framework, we were able to compare the vaccination failure rate in a group of dogs entering the Italian border from EU and non-EU countries to those vaccinated in Italy prior to international travel. Our analysis identified that cross-breeds and two breed categories showed high vaccine success rates, while Beagles and Boxers were the least likely to show a successful response to vaccination (88.82% and 90.32%, respectively). Our analysis revealed diverse performances among the commercially available vaccines, in terms of serological peak windows, and marked differences according to geographical area. Of note, we found a higher vaccine failure rate in imported dogs (13.15%) than in those vaccinated in Italy (5.89%). Our findings suggest that the choice of vaccine may influence the likelihood of an animal achieving a protective serological level and that time from vaccination to sampling should be considered when interpreting serological results. A higher vaccine failure in imported compared to Italian dogs highlights the key role that border controls still have in assessing the full compliance of pet movements with EU legislation to minimize the risk of rabies being reintroduced into a disease-free area
CM from intact hAM: an easily obtained product with relevant implications for translation in regenerative medicine
Background: It is now well established that factors (free or in extracellular vesicles) secreted by mesenchymal stromal cells (MSC) are important mediators of MSC regenerative actions. Herein we produced the secretome (conditioned medium, CM) from MSC isolated from the amniotic membrane (hAMSC) and CM from the intact amniotic membrane (hAM, no manipulation or enzymatic digestion) in order to potentially identify an effective, easy and less expensive secretome to produce for potential applications in regenerative medicine. Given that immunomodulation is a key mechanism of action through which hAMSC contributes to tissue regeneration, we used a comprehensive panel of in vitro immunomodulatory tests to compare the CMs. Methods: Amniotic membranes were either cut into fragments or used for hAMSC isolation. CMs from hAMSC at passages 0 and 2 were collected after a standard 5-day culture while CM from hAM was collected after a 2- and 5-day culture. Immunomodulation was assessed in terms of PBMC and T-cell proliferation, T-cell subset polarization, T-regulatory cell induction, cell cytotoxicity and monocyte differentiation toward antigen-presenting cells. Furthermore, we performed a comparison between CM obtained from single donors and pooled CM. We also assessed the impact of lyophilization on the immunomodulatory properties of CM. Results: We demonstrate that CM from hAM has comparable immunomodulatory properties to CM from hAMSC at passages 0 and 2. Furthermore, we demonstrate that pooled CMs have similar effects when compared to CM from single donors used separately. Finally, we demonstrate that lyophilization does not alter the in vitro immunomodulatory properties of CM from hAM and hAMSC. Conclusions: The results presented herein support the possibility to produce secretome from intact hAM and open the prospect to highly improve the scalability of the GMP production process while reducing the costs and time related to the process of cell isolation and expansion. Moreover, the possibility of having a lyophilized secretome that maintains its original properties would allow for a ready-to-use product with easier handling, shipping and storage. The use of a lyophilized product will also facilitate clinicians by permitting customized reconstitution volumes and methods according to the most suitable formula required by the clinical application
Murine neural stem cells model Hunter disease in vitro: glial cell-mediated neurodegeneration as a possible mechanism involved
Mucopolysaccharidosis type II (MPSII or Hunter Syndrome) is a lysosomal storage disorder caused by the deficit of iduronate 2-sulfatase (IDS) activity and characterized by progressive systemic and neurological impairment. As the early mechanisms leading to neuronal degeneration remain elusive, we chose to examine the properties of neural stem cells (NSCs) isolated from an animal model of the disease in order to evaluate whether their neurogenic potential could be used to recapitulate the early phases of neurogenesis in the brain of Hunter disease patients. Experiments here reported show that NSCs derived from the subventricular zone (SVZ) of early symptomatic IDS-knockout (IDS-ko) mouse retained self-renewal capacity in vitro, but differentiated earlier than wild-type (wt) cells, displaying an evident lysosomal aggregation in oligodendroglial and astroglial cells. Consistently, the SVZ of IDS-ko mice appeared similar to the wt SVZ, whereas the cortex and striatum presented a disorganized neuronal pattern together with a significant increase of glial apoptotic cells, suggesting that glial degeneration likely precedes neuronal demise. Interestingly, a very similar pattern was observed in the brain cortex of a Hunter patient. These observations both in vitro, in our model, and in vivo suggest that IDS deficit seems to affect the late phases of neurogenesis and/or the survival of mature cells rather than NSC self-renewal. In particular, platelet-derived growth factor receptor-\u3b1-positive (PDGFR-\u3b1+) glial progenitors appeared reduced in both the IDS-ko NSCs and in the IDS-ko mouse and human Hunter brains, compared with the respective healthy controls. Treatment of mutant NSCs with IDS or PDGF throughout differentiation was able to increase the number of PDGFR-\u3b1+ cells and to reduce that of apoptotic cells to levels comparable to wt. This evidence supports IDS-ko NSCs as a reliable in vitro model of the disease, and suggests the rescue of PDGFR-\u3b1+ glial cells as a therapeutic strategy to prevent neuronal degeneration