Slow and steady wins the race: Fractionated near-infrared treatment empowered by graphene-enhanced 3D scaffolds for precision oncology

Surgically addressing tumors poses a challenge, requiring a tailored, multidisciplinary approach for each patient based on the unique aspects of their case. Innovative therapeutic regimens combined to reliable reconstructive methods can contribute to an extended patient's life expectancy. This study presents a detailed comparative investigation of near-infrared therapy protocols, examining the impact of non-fractionated and fractionated irradiation regimens on cancer treatment. The therapy is based on the implantation of graphene oxide/poly(lactic-co-glycolic acid) three-dimensional printed scaffolds, exploring their versatile applications in oncology by the examination of pro-inflammatory cytokine secretion, immune response, and in vitro and in vivo tumor therapy. The investigation into cell death patterns (apoptosis vs necrosis) underlines the pivotal role of protocol selection underscores the critical influence of treatment duration on cell fate, establishing a crucial parameter in therapeutic decision-making. In vivo experiments corroborated the profound impact of protocol selection on tumor response. The fractionated regimen emerged as the standout performer, achieving a substantial reduction in tumor size over time, surpassing the efficacy of the non-fractionated approach. Additionally, the fractionated regimen exhibited efficacy also in targeting tumors in proximity but not in direct contact to the scaffolds. Our results address a critical gap in current research, highlighting the absence of a standardized protocol for optimizing the outcome of photodynamic therapy. The findings underscore the importance of personalized treatment strategies in achieving optimal therapeutic efficacy for precision cancer therapy.

Disclosing the molecular profile of the human amniotic mesenchymal stromal cell secretome by filter-aided sample preparation proteomic characterization

BACKGROUND

The secretome of mesenchymal stromal cells isolated from the amniotic membrane (hAMSCs) has been extensively studied for its in vitro immunomodulatory activity as well as for the treatment of several preclinical models of immune-related disorders. The bioactive molecules within the hAMSCs secretome are capable of modulating the immune response and thus contribute to stimulating regenerative processes. At present, only a few studies have attempted to define the composition of the secretome, and several approaches, including multi-omics, are underway in an attempt to precisely define its composition and possibly identify key factors responsible for the therapeutic effect.

METHODS

In this study, we characterized the protein composition of the hAMSCs secretome by a filter-aided sample preparation (FASP) digestion and liquid chromatography-high resolution mass spectrometry (LC-MS) approach. Data were processed for gene ontology classification and functional protein interaction analysis by bioinformatics tools.

RESULTS

Proteomic analysis of the hAMSCs secretome resulted in the identification of 1521 total proteins, including 662 unique elements. A number of 157 elements, corresponding to 23.7%, were found as repeatedly characterizing the hAMSCs secretome, and those that resulted as significantly over-represented were involved in immunomodulation, hemostasis, development and remodeling of the extracellular matrix molecular pathways.

CONCLUSIONS

Overall, our characterization enriches the landscape of hAMSCs with new information that could enable a better understanding of the mechanisms of action underlying the therapeutic efficacy of the hAMSCs secretome while also providing a basis for its therapeutic translation.

Amniotic Membrane-Derived Stromal Cells Release Extracellular Vesicles That Favor Regeneration of Dystrophic Skeletal Muscles

Duchenne muscular dystrophy (DMD) is a muscle disease caused by mutations in the dystrophin gene characterized by myofiber fragility and progressive muscle degeneration. The genetic defect results in a reduced number of self-renewing muscle stem cells (MuSCs) and an impairment of their activation and differentiation, which lead to the exhaustion of skeletal muscle regeneration potential and muscle replacement by fibrotic and fatty tissue. In this study, we focused on an unexplored strategy to improve MuSC function and to preserve their niche based on the regenerative properties of mesenchymal stromal cells from the amniotic membrane (hAMSCs), that are multipotent cells recognized to have a role in tissue repair in different disease models. We demonstrate that the hAMSC secretome (CM hAMSC) and extracellular vesicles (EVs) isolated thereof directly stimulate the in vitro proliferation and differentiation of human myoblasts and mouse MuSC from dystrophic muscles. Furthermore, we demonstrate that hAMSC secreted factors modulate the muscle stem cell niche in dystrophic-mdx-mice. Interestingly, local injection of EV hAMSC in mdx muscles correlated with an increase in the number of activated Pax7+/Ki67+ MuSCs and in new fiber formation. EV hAMSCs also significantly reduced muscle collagen deposition, thus counteracting fibrosis and MuSCs exhaustion, two hallmarks of DMD. Herein for the first time we demonstrate that CM hAMSC and EVs derived thereof promote muscle regeneration by supporting proliferation and differentiation of resident muscle stem cells. These results pave the way for the development of a novel treatment to counteract DMD progression by reducing fibrosis and enhancing myogenesis in dystrophic muscles.

Mapping of the Human Amniotic Membrane: In Situ Detection of Microvesicles Secreted by Amniotic Epithelial Cells

The potential clinical applications of human amniotic membrane (hAM) and human amniotic epithelial cells (hAECs) in the field of regenerative medicine have been known in literature since long. However, it has yet to be elucidated whether hAM contains different anatomical regions with different plasticity and differentiation potential. Recently, for the first time, we highlighted many differences in terms of morphology, marker expression, and differentiation capabilities among four distinct anatomical regions of hAM, demonstrating peculiar functional features in hAEC populations. The aim of this study was to investigate in situ the ultrastructure of the four different regions of hAM by means of transmission electron microscopy (TEM) to deeply understand their peculiar characteristics and to investigate the presence and localization of secretory products because to our knowledge, there are no similar studies in the literature. The results of this study confirm our previous observations of hAM heterogeneity and highlight for the first time that hAM can produce extracellular vesicles (EVs) in a heterogeneous manner. These findings should be considered to increase efficiency of hAM applications within a therapeutic context.

Alarming trends in Tobacco use in high school Tunisian adolescents: MedSPAD2013-2021

Background

Tobacco use is a global health concern, with smoking initiation often beginning in adolescence. In Tunisia, published data assessing trends of tobacco consumption at the national level only concerns middle school students aged 13 to 15 years. No data related to high school students are however published yet. We aimed to determine tobacco smoking prevalence in Tunisian adolescents and assess trends from 2013 to 2021.

Methods

Pooled data from three Mediterranean school surveyson alcohol and other drugs (MedSPAD surveys: 2013, 2017, and 2021) were used. Based on three-stage stratification sampling method, teenagers aged between 15 and 17 years, were enrolled. Were not included students enrolled in vocational training centers and out-of-school adolescents. Data collection was performed using a self-administered standardized questionnaire assessing socio-demographic characteristics and risky behaviours. We studied weighted prevalence estimates of cigarettes and water pipe (WP) smoking. All statistical analysis, including trend analysis, were performed with STATA software.

Results

A total of 14.723 students were enrolled with sex ratio (M/F) equal to 0.6 and mean age of 16.2±0.8 years. The prevalence of cigarette smoking increased from 17.8%, to 20.2% then to 24.7% for 2013, 2017 and 2021, respectively. As for WP smoking, its prevalence increased from 14.8%, to 16.7% then to 19.9% for 2013, 2017 and 2021, respectively. Trends analysis concluded to significant increase over study period for cigarettes and WP smoking (p < 10-3). The increase was most alarming for girls regarding WP smoking (consistent increase over the study period).

Conclusions

Our findings underscore the alarming increasing trend for different forms of tobacco smoking among Tunisian youth. It is therefore crucial to strengthen tobacco control measures among young adolescents in order to counteract the tobacco industry’s expanding marketing of new products primarily targeting this population.

Key messages

• The prevalence of cigarette and water pipe smoking increased significantly among high school Tunisian adolescents from 2013 to 2021.

• A better commitment to the implementation of MPOWER measures for tobacco control is therefore urgent.

Leading causes of death in Tunisia, 2020

Background

Mortality data represent a primary source of information for monitoring a population health status over years. In Tunisia, the national Information System on Causes of Death (ISCD) lacks completeness (average coverage rate of 40%); however, in order to examine covid-19’s effect on mortality data, the ISCD was reinforced. We aimed to give an overview of leading causes of death in Tunisia for 2020.

Methods

Data were obtained from Medical Certificates of Cause Of Death (MCCOD) sent by municipalities to the National Institute of Health in accordance with the legislative framework. Causes of Death (CoD) coding process was performed based on the International Classification of Diseases, Tenth Revision (ICD-10). The underlying cause of death was identified based on IRIS software, and mortality statistics were presented based on the world health organization cause-of-death lists for tabulating mortality statistics. Data analysis was performed using SPSS software.

Results

A total of 46.420 MCCOD among 75.365 deaths officially declared by the National Institute of Statistics, were analyzed (coverage rate of 61.2%). The 10 leading causes of death for both sexes, in rank order were: diabetes mellitus, cerebrovascular diseases, covid-19, ischemic heart diseases, external causes of death, digestive and pulmonary malignant neoplasms, conditions of neonatal period, hypertensive diseases, and influenza and pneumonia. Leading causes of infant deaths were: certain conditions originating in perinatal period, congenital malformations, deformations and chromosomal abnormalities, diseases of respiratory system, certain infectious and parasitic diseases, and diseases of nervous system.

Conclusions

The COVID-19 pandemic was an opportunity to improve the Tunisian ISCD’s coverage rate. However, efforts should be maintained to optimize system completeness, and decision makers should be more sensitized regarding the urgent need for system digitalization.

Key messages

• Mortality statistics have shown that covid-19 ranks third among leading causes of death in Tunisia for 2020; and non communicable disease accounted for 6 out of 10 leading causes of deaths.

• The ISCD coverage rate was improved in 2020 reaching 61.2%; however the system digitalization is an essential and sustainable solution to optimize completeness.

Cannabis use in Tunisian adolescents: Alarming trends from 2013 to 2021

Background

Cannabis is the most widely used illicit psychoactive substance worldwide. In Tunisia, the prevalence of cannabis use and its association with other risky behaviours were reported in several publications interesting mainly early adolescence. However, no publications exploring trends based on national epidemiological data are available yet. Our purpose was to determine cannabis prevalence in Tunisian high school adolescents and assess significant trends from 2013 to 2021.

Methods

Pooled data from Mediterranean school surveys on alcohol and other drugs conducted in 2013, 2017, and 2021, were used. Based on three-stage stratification sampling method, first and second grade secondary education students were enrolled. Were not included students enrolled in vocational training centers and out-of-school adolescents. Self-administered standardized questionnaire was used in data collection. We studied weighted lifetime prevalence of cannabis use and chi square test for trend was used for global, by gender and by sector (private/public) trends assessement. STATA software was used for statistical analysis.

Results

A total of 14.723 students were enrolled with sex ratio (M/F) equal to 0.61 and mean age of 16.2±0.8 years. The prevalence of cannabis use increased from 1.4%, to 3.8% then to 7.9% for 2013, 2017 and 2021 respectively. Trend assessement concludes to significant increase in overall cannabis use (p &lt; 10-3). Besides, there was a significant increase in both public and private schools, and among both boys and girls. However, the greatest increase was among male students (3.5% in 2013, 9.2% in 2017 and 16.1% in 2021) (p &lt; 10-3).

Conclusions

Despite the reinforcement of restrictive legislative measures, the prevalence of cannabis use among Tunisian high school adolescents is significantly increasing. Moreover, it’s important to further investigate problematic cannabis use and its effects on adolescents’ physical and mental health.

Key messages

• Trend assessement confirmed the significant increase in lifetime cannabis use in high school adolescents in Tunisia, for both sexes and for both private and public sector.

• This alarming public health issue requires urgent legislation review and close multisectoral collaboration to control supply and demand.

Nonmedical use of anxiolytics among Tunisian students: Connecting the dots from 2013 to 2021

Background

Nonmedical use of prescription drugs such as sedatives and anxiolytics is a fast growing public health threat in several countries. In Tunisia, although several studies have investigated the prevalence of nonmedical use of anxiolytics among school-age students, there is a gap in knowledge regarding trends in anxiolytics misuse. We aimed to determine the prevalence of nonmedical use of anxiolytics and examine trends between 2013 and 2021.

Methods

Pooled data from three Mediterranean school surveys on alcohol and other drugs (MedSPAD I-2013, MedSPAD II-2017, MedSPAD III-2021) were used. Based on three-stage stratification sampling method, teenagers in first and second grades of secondary education, were enrolled. Were not included students enrolled in vocational training centers and out-of-school adolescents. Data collection was performed using a self-administered standardized questionnaire. We studied weighted lifetime nonmedical use of

prescription anxiolytics and performed global and by gender trend analysis. Epi data software was used for data entry and all statistical analysis, were performed with STATA software.

Results

A total of 14.723 students were enrolled with sex ratio (Male/Female) equal to 0.61 and mean age of 16.2±0.8 years. The prevalence of nonmedical anxiolytics’ use increased from 2.1% to 3% then to 8.4% for 2013, 2017 and 2021, respectively. Global and by gender trends analysis concluded to significant increase from 2017 to 2021 (p &lt; 10-3). However, a non-significant increase was revealed from 2013 to 2017.

Conclusions

Our study is the first to confirm a significant increasing trend in non-medical use of anxiolytics among Tunisian adolescents. These findings emphasize the urgent need for early detection of psychological vulnerability among adolescents in order to prevent their engagement in such risky behaviors.

Key messages

• Decision makers should be sensitized regarding the alarming increasing trend in non-medical use of anxiolytics, among Tunisian adolescents.

• The state control of these substances accessibility and early detection of psychological vulnerability, are highly required.

Percutaneous edge-to-edge repair for systemic tricuspid valve regurgitation in patients with congenital heart disease: the first descriptive cohort

 

In patients with congenital heart diseases (CHD) systemic tricuspid regurgitation (STR) is frequent.

Here, we report our experience with percutaneous edge-to-edge repair (PETER) in a series of 12 CHD patients with STR using the MitraClip system.

Twelve patients (median age = 35 years, 83% males) with severe STR (ccTGA (n=5), asTGA (n=3), SV (n=4)), at high-risk for surgical treatment, gave informed consent for treatment using PETER. The XTR MitraClip device (Abbott, Santa Clara, CA) was used. At baseline, 7/12 patients were in NYHA functional class ≥ III. Standard femoral venous access was successfully used in 10/12 patients. In SV patients, the systemic valve was accessed directly through the right atrium (n=2), after a Fontan conduit puncture (n=1), or after direct atrial surgical access (n=1). In TGA patients, either transseptal (ccTGA patients, n=4) or transbaffle (asTGA patients, n=3) puncture was performed (4).

Mitraclip devices were successfully implanted in 11/12 patients (Figure 1). One procedural complication was reported for a patient with SV in whom a septal leaflet rupture occurred following clip release, leading to severe STR; the patient died from refractory cardiac failure one week later. Peri-procedural complications included one case of left femoral vein injury and one case of atrial flutter treated by catheter ablation. After a median follow-up of 12-months (range 1–25) following device implantation, no death had occurred. The patients had significant reduction in STR (from severe to moderate in 10/11 patients) and clinically improved (10/11 patients were in NYHA class I or II).

To conclude, percutaneous edge-to-edge therapy of STR in CHD patients is feasible, safe and effective to reduce STR and SRV dilatation. This reduction is associated with a significant clinical improvement.

Funding Acknowledgement

Type of funding sources: None.

Assessment of the in vivo biofunctionality of a biomimetic hybrid scaffold for osteochondral tissue regeneration

Chondral and osteochondral lesions represent one of the most challenging problems in the orthopedic field, as these types of injuries lead to disability and worsened quality of life for patients and have an economic impact on the healthcare system. The aim of this in vivo study was to develop a new tissue engineering approach through a hybrid scaffold for osteochondral tissue regeneration made of porous polyurethane foam (PU) coated under vacuum with calcium phosphates (PU/VAC). Scaffold characterization showed a highly porous and interconnected structure. Human amniotic mesenchymal stromal cells (hAMSCs) were loaded into scaffolds using pectin (PECT) as a carrier. Osteochondral defects in medial femoral condyles of rabbits were created and randomly allocated in one of the following groups: plain scaffold (PU/VAC), scaffold with hAMSCs injected in the implant site (PU/VAC/hAMSC), scaffold with hAMSCs loaded in pectin (PU/VAC/PECT/hAMSC), and no treated defects (untreated). The therapeutic efficacy was assessed by macroscopic, histological, histomorphometric, microtomographic, and ultrastructural analyses at 3, 6, 12, and 24 weeks. Histological results showed that the scaffold was permissive to tissue growth and penetration, an immature osteocartilaginous tissue was observed at early experimental times, with a more accentuated bone regeneration in comparison with the cartilage layer in the absence of any inflammatory reaction.

Priming with inflammatory cytokines is not a prerequisite to increase immune-suppressive effects and responsiveness of equine amniotic mesenchymal stromal cells

BACKGROUND

Equine amniotic mesenchymal stromal cells (AMSCs) and their conditioned medium (CM) were evaluated for their ability to inhibit in vitro proliferation of peripheral blood mononuclear cells (PBMCs) with and without priming. Additionally, AMSC immunogenicity was assessed by expression of MHCI and MHCII and their ability to counteract the in vitro inflammatory process.

METHODS

Horse PBMC proliferation was induced with phytohemagglutinin. AMSC priming was performed with 10 ng/ml of TNF-α, 100 ng/ml of IFN-γ, and a combination of 5 ng/ml of TNF-α and 50 ng/ml of IFN-γ. The CM generated from naïve unprimed and primed AMSCs was also tested to evaluate its effects on equine endometrial cells in an in vitro inflammatory model induced by LPS. Immunogenicity marker expression (MHCI and II) was evaluated by qRT-PCR and by flow cytometry.

RESULTS

Priming does not increase MHCI and II expression. Furthermore, the inhibition of PBMC proliferation was comparable between naïve and conditioned cells, with the exception of AMSCs primed with both TNF-α and IFN-γ that had a reduced capacity to inhibit T cell proliferation. However, AMSC viability was lower after priming than under other experimental conditions. CM from naïve and primed AMSCs strongly inhibited PBMC proliferation and counteracted the inflammatory process, rescuing about 65% of endometrial cells treated by LPS.

CONCLUSION

AMSCs and their CM have a strong capacity to inhibit PBMC proliferation, and priming is not necessary to improve their immunosuppressive activity or reactivity in an inflammatory in vitro model.

The Immunomodulatory Properties of Amniotic Cells: The Two Sides of the Coin

Among the many cell types useful in developing therapeutic treatments, human amniotic cells from placenta have been proposed as valid candidates. Both human amniotic epithelial and mesenchymal stromal cells, and the conditioned medium generated from their culture, exert multiple immunosuppressive activities. Indeed, they inhibit T and B cell proliferation, suppress inflammatory properties of monocytes, macrophages, dendritic cells, neutrophils, and natural killer cells, while promoting induction of cells with regulatory functions such as regulatory T cells and anti-inflammatory M2 macrophages. These properties have laid the foundation for their use for the treatment of inflammatory-based diseases, and encouraging results have been obtained in different preclinical disease models where exacerbated inflammation is present. Moreover, an immune-privileged status of amniotic cells has been often highlighted. However, even if long-term engraftment of amniotic cells has been reported into immunocompetent animals, only few cells survive after infusion. Furthermore, amniotic cells have been shown to be able to induce immune responses in vivo and, under specific culture conditions, they can stimulate T cell proliferation in vitro. Although immunosuppressive properties are a widely recognized characteristic of amniotic cells, immunogenic and stimulatory activities appear to be less reported, sporadic events. In order to improve therapeutic outcome, the mechanisms responsible for the suppressive versus stimulatory activity need to be carefully addressed. In this review, both the immunosuppressive and immunostimulatory activity of amniotic cells will be discussed.

Mapping of the Human Placenta: Experimental Evidence of Amniotic Epithelial Cell Heterogeneity

The human placenta is an important source of stem cells that can be easily collected without ethical concerns since it is usually discarded after childbirth. In this study, we analyzed the amniotic membrane (AM) from the human placenta with the aim of mapping different regions with respect to their morpho-functional features and regenerative potential. AMs were obtained from 24 healthy women, undergoing a caesarean section, and mapped into 4 different regions according to their position in relation to the umbilical cord: the central, intermediate, peripheral, and reflected areas. We carried out a multiparametric analysis focusing our attention on amniotic epithelial cells (AECs). Our results revealed that AECs, isolated from the different areas, are a heterogeneous cell population with different pluripotency and proliferation marker expression (octamer-binding transcription factor 4 [OCT-4], tyrosine-protein kinase KIT [c-KIT], sex determining region Y-box 2 [SOX-2], α-fetoprotein, cyclic AMP response element binding [CREB] protein, and phosphorylated active form of CREB [p-CREB]), proliferative ability, and osteogenic potential. Our investigation discloses interesting findings that could be useful for increasing the efficiency of AM isolation and application for therapeutic purposes.

Therapeutic potential of hAECs for early Achilles tendon defect repair through regeneration

Cell-based therapy holds great promise for tendon disorders, a widespread debilitating musculoskeletal condition. Even if the cell line remains to be defined, preliminary evidences have proven that amniotic-derived cells possess in vitro and in vivo a great tenogenic potential. This study investigated the efficacy of transplanted human amniotic epithelial cells (hAECs) by testing their early regenerative properties and mechanisms involved on a validated ovine Achilles tendon partial defect performed on 29 animals. The injured tendons treated with hAECs recovered rapidly, in 28 days, structural and biomechanical properties undertaking a programmed tissue regeneration, differently from the spontaneous healing tissues. hAECs remained viable within the host tendons establishing with the endogenous progenitor cells an active dialogue. Through the secretion of modulatory factors, hAECs inhibited the inflammatory cells infiltration, activated the M2 macrophage subpopulation early recruitment, and accelerated blood vessel as well as extracellular matrix remodelling. In parallel, some in situ differentiated hAECs displayed a tenocytelike phenotype. Both paracrine and direct hAECs stimulatory effects were confirmed analysing their genome profile before and after transplantation. The 49 human up-regulated transcripts recorded in transplanted hAECs belonged to tendon lineage differentiation (epithelial-mesenchymal transition, connective specific matrix components, and skeleton or muscle system development-related transcripts), as well as the in situ activation of paracrine signalling involved in inflammatory and immunomodulatory response. Altogether, these evidences support the hypothesis that hAECs are a practicable and efficient strategy for the acute treatment of tendinopathy, reinforcing the idea of a concrete use of amniotic epithelial cells towards the clinical practice.

Trypsinogen 4 boosts tumor endothelial cells migration through proteolysis of tissue factor pathway inhibitor-2

Proteases contribute to cancer in many ways, including tumor vascularization and metastasis, and their pharmacological inhibition is a potential anticancer strategy. We report that human endothelial cells (EC) express the trypsinogen 4 isoform of the serine protease 3 (PRSS3), and lack both PRSS2 and PRSS1. Trypsinogen 4 expression was upregulated by the combined action of VEGF-A, FGF-2 and EGF, angiogenic factors representative of the tumor microenvironment. Suppression of trypsinogen 4 expression by siRNA inhibited the angiogenic milieu-induced migration of EC from cancer specimens (tumor-EC), but did not affect EC from normal tissues. We identified tissue factor pathway inhibitor-2 (TFPI-2), a matrix associated inhibitor of cell motility, as the functional target of trypsinogen 4, which cleaved TFPI-2 and removed it from the matrix put down by tumor-EC. Silencing tumor-EC for trypsinogen 4 accumulated TFPI2 in the matrix. Showing that angiogenic factors stimulate trypsinogen 4 expression, which hydrolyses TFPI-2 favoring a pro-migratory situation, our study suggests a new pathway linking tumor microenvironment signals to endothelial cell migration, which is essential for angiogenesis and blood vessel remodeling. Abolishing trypsinogen 4 functions might be an exploitable strategy as anticancer, particularly anti-vascular, therapy.

Human amnion favours tissue repair by inducing the M1-to-M2 switch and enhancing M2 macrophage features

Human amniotic mesenchymal cells (hAMTCs) possess interesting immunomodulatory properties, making them attractive candidates for regenerative medicine applications. Recent in vivo reports argue in favour of an important role for macrophages as targets of hAMTC‐mediated suppression of inflammation and the enhancement of tissue repair. However, a comprehensive study of the effects of hAMTCs and their conditioned medium (CM) on human macrophage differentiation and function is unavailable. In the present study we found that hAMTCs and CM induce the differentiation of myeloid cells (U937 and monocytes) towards macrophages. We then investigated their effects on monocytes differentiated toward pro‐inflammatory M1 and anti‐inflammatory M2 macrophages. Monocytes treated under M1 conditions in the presence of hAMTCs or CMs shifted towards M2‐like macrophages, which expressed CD14, CD209, CD23, CD163 and PM‐2 K, possessed higher phagocytic activity and produced higher IL‐10 and lower pro‐inflammatory cytokines. They were also poor T cell stimulators and Th1 inducers, while they were able to increase activated and naïve suppressive Treg subsets. We show that prostaglandins, and not IL‐6, play a role in determining the M2 activation status. Instead, monocytes treated under M2 conditions in the presence of hAMTCs or CM retained M2‐like features, but with an enhanced anti‐inflammatory profile, having a reduced expression of the co‐stimulatory molecule CD80, reduced phagocytosis activity and decreased the secretion of inflammatory chemokines. Importantly, we provide evidence that macrophages re‐educated by CM improve tissue regeneration/repair in wound‐healing models. In conclusion, we identified new cell targets of hAMTCs and their bioactive factors and here provide insight into the beneficial effects observed when these cells are used in therapeutic approaches in vivo. © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd.

Internalization of nanopolymeric tracers does not alter characteristics of placental cells

In the cell therapy scenario, efficient tracing of transplanted cells is essential for investigating cell migration and interactions with host tissues. This is fundamental to provide mechanistic insights which altogether allow for the understanding of the translational potential of placental cell therapy in the clinical setting. Mesenchymal stem/stromal cells (MSC) from human placenta are increasingly being investigated for their potential in treating patients with a variety of diseases. In this study, we investigated the feasibility of using poly (methyl methacrylate) nanoparticles (PMMA‐NPs) to trace placental MSC, namely those from the amniotic membrane (hAMSC) and early chorionic villi (hCV‐MSC). We report that PMMP‐NPs are efficiently internalized and retained in both populations, and do not alter cell morphofunctional parameters. We observed that PMMP‐NP incorporation does not alter in vitro immune modulatory capability of placental MSC, a characteristic central to their reparative/therapeutic effects in vitro. We also show that in vitro, PMMP‐NP uptake is not affected by hypoxia. Interestingly, after in vivo brain ischaemia and reperfusion injury achieved by transient middle cerebral artery occlusion (tMCAo) in mice, iv hAMSC treatment resulted in significant improvement in cognitive function compared to PBS‐treated tMCAo mice. Our study provides evidence that tracing placental MSC with PMMP‐NPs does not alter their in vitro and in vivo functions. These observations are grounds for the use of PMMP‐NPs as tools to investigate the therapeutic mechanisms of hAMSC and hCV‐MSC in preclinical models of inflammatory‐driven diseases.

Amniotic membrane mesenchymal cells-derived factors skew T cell polarization toward Treg and downregulate Th1 and Th17 cells subsets

We previously demonstrated that cells derived from the mesenchymal layer of the human amniotic membrane (hAMSC) and their conditioned medium (CM-hAMSC) modulate lymphocyte proliferation in a dose-dependent manner. In order to understand the mechanisms involved in immune regulation exerted by hAMSC, we analyzed the effects of CM-hAMSC on T-cell polarization towards Th1, Th2, Th17, and T-regulatory (Treg) subsets. We show that CM-hAMSC equally suppresses the proliferation of both CD4⁺ T-helper (Th) and CD8⁺ cytotoxic T-lymphocytes. Moreover, we prove that the CM-hAMSC inhibitory ability affects both central (CD45RO⁺CD62L⁺) and effector memory (CD45RO⁺CD62L⁻) subsets. We evaluated the phenotype of CD4⁺ cells in the MLR setting and showed that CM-hAMSC significantly reduced the expression of markers associated to the Th1 (T-bet⁺CD119⁺) and Th17 (RORγt⁺CD161⁺) populations, while having no effect on the Th2 population (GATA3⁺CD193⁺/GATA3⁺CD294⁺cells). T-cell subset modulation was substantiated through the analysis of cytokine release for 6 days during co-culture with alloreactive T-cells, whereby we observed a decrease in specific subset-related cytokines, such as a decrease in pro-inflammatory, Th1-related (TNFα, IFNγ, IL-1β), Th2 (IL-5, IL-6), Th9 (IL-9), and Th17 (IL-17A, IL-22). Furthermore, CM-hAMSC significantly induced the Treg compartment, as shown by an induction of proliferating CD4⁺FoxP3⁺ cells, and an increase of CD25⁺FoxP3⁺ and CD39⁺FoxP3⁺ Treg in the CD4⁺ population. Induction of Treg cells was corroborated by the increased secretion of TGF-β. Taken together, these data strengthen the findings regarding the immunomodulatory properties of CM-hAMSC derived from human amniotic membrane MSC, and in particular provide insights into their effect on regulation of T cell polarization.

Isolation, Culture, and Phenotypic Characterization of Mesenchymal Stromal Cells from the Amniotic Membrane of the Human Term Placenta

During the past several years, the human placenta and in particular the amniotic fetal membrane have attracted much attention as a possible source of cells to be used in cell therapy approaches due to its putative stem cell potential associated with its early embryonic origin and its immunomodulatory potential associated with its role in fetomaternal tolerance.Within the human amniotic membrane, it is possible to isolate two main cell populations: amniotic epithelial cells (from the epithelial layer of the amniotic membrane) and amniotic mesenchymal cells (from the mesenchymal layer of the amniotic membrane). In this chapter, we will describe a method for the isolation of mesenchymal stromal cells (hAMSCs). We will also describe their optimal culture conditions and the phenotypic characterization of cells after passaging.

Amniotic mesenchymal cells from pre-eclamptic placentae maintain immunomodulatory features as healthy controls

Pre‐eclampsia (PE) is one of the most severe syndromes in human pregnancy, and the underlying mechanisms of PE have yet to be determined. Pre‐eclampsia is characterized by the alteration of the immune system's activation status, an increase in inflammatory Th1/Th17/APC cells, and a decrease in Th2/Treg subsets/cytokines. Moreover, inflammatory infiltrates have been detected in the amniotic membranes of pre‐eclamptic placentae, and to this date limited data are available regarding the role of amniotic membrane cells in PE. Interestingly, we and others have previously shown that human amniotic mesenchymal stromal cells (hAMSC) possess anti‐inflammatory properties towards almost all immune cells described to be altered in PE. In this study we investigated whether the immunomodulatory properties of hAMSC were altered in PE. We performed a comprehensive study of cell phenotype and investigated the in vitro immunomodulatory properties of hAMSC isolated from pre‐eclamptic pregnancies (PE‐hAMSC), comparing them to hAMSC from normal pregnancies (N‐hAMSC). We demonstrate that PE‐hAMSC inhibit CD4/CD8 T‐cell proliferation, suppress Th1/Th2/Th17 polarization, induce Treg and block dendritic cells and M1 differentiation switching them to M2 cells. Notably, PE‐hAMSC generated a more prominent induction of Treg and higher suppression of interferon‐γ when compared to N‐hAMSC, and this was associated with higher transforming growth factor‐β1 secretion and PD‐L2/PD‐L1 expression in PE‐hAMSC. In conclusion, for the first time we demonstrate that there is no intrinsic impairment of the immunomodulatory features of PE‐hAMSC. Our results suggest that amniotic mesenchymal stromal cells do not contribute to the disease, but conversely, could participate in offsetting the inflammatory environment which characterizes PE.

Human amniotic mesenchymal stromal cells (hAMSCs) as potential vehicles for drug delivery in cancer therapy: an in vitro study

INTRODUCTION

In the context of drug delivery, mesenchymal stromal cells (MSCs) from bone marrow and adipose tissue have emerged as interesting candidates due to their homing abilities and capacity to carry toxic loads, while at the same time being highly resistant to the toxic effects. Amongst the many sources of MSCs which have been identified, the human term placenta has attracted particular interest due to its unique, tissue-related characteristics, including its high cell yield and virtually absent expression of human leukocyte antigens and co-stimulatory molecules. Under basal, non-stimulatory conditions, placental MSCs also possess basic characteristics common to MSCs from other sources. These include the ability to secrete factors which promote cell growth and tissue repair, as well as immunomodulatory properties. The aim of this study was to investigate MSCs isolated from the amniotic membrane of human term placenta (hAMSCs) as candidates for drug delivery in vitro.

METHODS

We primed hAMSCs from seven different donors with paclitaxel (PTX) and investigated their ability to resist the cytotoxic effects of PTX, to upload the drug, and to release it over time. We then analyzed whether the uptake and release of PTX was sufficient to inhibit proliferation of CFPAC-1, a pancreatic tumor cell line sensitive to PTX.

RESULTS

For the first time, our study shows that hAMSCs are highly resistant to PTX and are not only able to uptake the drug, but also release it over time. Moreover, we show that PTX is released from hAMSCs in a sufficient amount to inhibit tumor cell proliferation, whilst some of the PTX is also retained within the cells.

CONCLUSION

Taken together, for the first time our results show that placental stem cells can be used as vehicles for the delivery of cytotoxic agents.

In vivo tracking of human placenta derived mesenchymal stem cells in nude mice via ¹⁴C-TdR labeling

Background

In order to shed light on the regenerative mechanism of mesenchymal stem cells (MSCs) in vivo, the bio-distribution profile of implanted cells using a stable and long-term tracking method is needed. We herein investigated the bio-distribution of human placental deciduas basalis derived MSCs (termed as PDB-MSCs) in nude mice after intravenous injection by carbon radioisotope labeling thymidine (¹⁴C-TdR), which is able to incorporate into new DNA strands during cell replication.

Results

The proliferation rate and radioactive emission of human PDB-MSCs after labeled with different concentrations of ¹⁴C-TdR were measured. PDB-MSCs labeled with 1 μCi possessed high radioactivity, and the biological characteristics (i.e. morphology, colony forming ability, differentiation capabilities, karyotype and cell cycle) showed no significant changes after labeling. Thus, 1 μCi was the optimal concentration in this experimental design. In nude mice, 1 × 10⁶¹⁴C-TdR-labeled PDB-MSCs were injected intravenously and the organs were collected at days 1, 2, 3, 5, 30 and 180 after injection, respectively. Radiolabeled PDB-MSCs were found mainly in the lung, liver, spleen, stomach and left femur of the recipient nude mice at the whole observation period.

Conclusions

This work provided solid evidence that ¹⁴C-TdR labeling did not alter the biological characteristics of human placental MSCs, and that this labeling method has potential to decrease the signal from non-infused or dead cells for cell tracking. Therefore, this labeling technique can be utilized to quantify the infused cells after long-term follow-up in pre-clinical studies.

Thrombospondin-1 is part of a Slug-independent motility and metastatic program in cutaneous melanoma, in association with VEGFR-1 and FGF-2

Differently from most transformed cells, cutaneous melanoma expresses the pleiotropic factor thrombospondin-1 (TSP-1). Herein, we show that TSP-1 (RNA and protein), undetectable in four cultures of melanocytes and a RGP melanoma, was variously present in 13 cell lines from advanced melanomas or metastases. Moreover, microarray analysis of 55 human lesions showed higher TSP-1 expression in primary melanomas and metastases than in common and dysplastic nevi. In a functional enrichment analysis, the expression of TSP-1 correlated with motility-related genes. Accordingly, TSP-1 production was associated with melanoma cell motility in vitro and lung colonization potential in vivo. VEGF/VEGFR-1 and FGF-2, involved in melanoma progression, regulated TSP-1 production. These factors were coexpressed with TSP-1 and correlated negatively with Slug (SNAI2), a cell migration master gene implicated in melanoma metastasis. We conclude that TSP-1 cooperates with FGF-2 and VEGF/VEGFR-1 in determining melanoma invasion and metastasis, as part of a Slug-independent motility program.

Isolation and characterization of plant growth promoting traits of a rhizobacteria: Pantoea agglomerans lma2

The use of microbial technology in agriculture is expanding quickly with the identification of new bacterial strains which are more effective in promoting the growth of plants. The rhizobacteria that promote the growth of plants can have a positive effect on the productivity of crops especially when subjected to salt stress. A nitrogen-fixing bacterium was isolated from the wheat rhizosphere of an arid region. The strain was identified on the basis of tests API20E and 16S rRNA sequencing, as Pantoea agglomerans lma2. This strain degraded several carbon sources: sugars (fructose, ribose, dextrin, salicin...), lipids (lecithin, tributyrin and tween 80), proteins (gelatin, casein), grew on KCN and could grow from pH 4 to 8 and had an optimum at pH 7. The growth temperature showed a maximum at 30 degrees C and the bacteria could tolerate from 4 to 41 degrees C and the growth rate was higher when the NaCl concentration was between 100 and 300 mM. The performance of activities enhancing the growth of plants of P. agglomerans lma2 was significantly better in the presence of salt. Rates of Indole Acetic Acid (IAA), siderophores production and solubilization of phosphate increased between 100 and 400 mM NaCl compared to the control without salt. The maximum values were saved to 300 mM for the production of siderophores (18.32%) and solubilization of phosphate (1061.49 microg mL(-1)) and 100 mM for the production of IAA (161 microg mL(-1)). A significant correlation existed between these three activities. These results showed that P. agglomerans lma2 with its Plant Growth Promoting Rhizobacteria (PGPR) and halophilic properties could constitute a good fertilizer in arid and saline zone.

Soluble factors of amnion-derived cells in treatment of inflammatory and fibrotic pathologies

Inflammation is a complex defense mechanism characterized by leukocyte migration from the vasculature into damaged tissues and subsequent deposition of extracellular matrix resulting in tissue repair. The inflammatory process is generally categorized into an acute, rapid response, and a persistent but slowly evolving chronic condition, which may progress into inflammatory diseases. An excessive deposition of extracellular matrix leads to overgrowth, hardening, and/or scarring of tissues, defined as fibrosis. The amnion has been used as biomaterial in medicine for over 100 years and has been proven valuable for the treatment of different pathological conditions including wound healing. In light of recent reports, this article will review the effects of the amnion and its cellular components within the inflammatory-fibrotic scenario and the factors described so far that could be involved in these immunomodulatory actions. As proof of principles, we will also discuss pre-clinical and clinical applications of the amnion where advantage has been taken of its anti-inflammatory and anti-fibrotic properties. It is conceivable that the local host environment in which the amnion is placed may have a profound role in influencing the production and function of soluble factors and the shift towards different steps in triggering healing. The healing effect depends on time, dosage, and location of cytokine/growth factor production by the amnion, together with the influence of the host microenvironment. Indeed, determining the specific cascade of events that may define the role of the amnion in a given clinical situation remains a challenge.

Effect of Azotobacter vinelandii and compatible solutes on germination wheat seeds and root concentrations of sodium and potassium under salt stress

The effect of plant growth-promoting Rhizobacteria (PGPR) and exogenous application of compatible solutes on seed germination and root concentrations of sodium and potassium of two wheat varieties (Triticum durum L.) were evaluated under saline stress. In this experiment, Azotobacter vinelandii strain DSM85, glycine betaine and proline were used. Inoculated seeds for each variety were placed on Whatman paper in 9 cm Petri dishes containing 15 mL of distilled water or NaCl solutions at various concentrations (control, 100, 200, 300 mM) supplemented with or without glycine betaine (GB) or proline at 5 mM. The results indicated that addition of proline (5 mM) stimulated the production of indol acetic acid and the growth of A. vinelandii at 200 and 300 mM NaCl, respectively. The germination rate index and the germination final percentage decreased significantly (p < 0.05) with increasing salinity level. The germination was significantly diminished at 300 mM with significant variation among varieties and Waha variety had higher germination percentage than Bousselam variety. Inoculation of seeds by A. vinelandii and exogenous application of proline had significantly positive effect on the germination at this concentration of NaCl. The rate of accumulation of Na+ in roots was important at 100 mM and increased at 200 mM. The concentration of K+ decreased when salinity increased. The effect of inoculation or inoculation with proline decreased the accumulation of Na' and reduced the loss of K+ under salt stress. From the present study we can conclude that the use of A. vinelandii strain DSM85 and external application of low concentrations of proline on seeds might be considered as a strategy for the protection of plants under saline stress.

Protease-activated receptor-1 (PAR-1) promotes the motility of human melanomas and is associated to their metastatic phenotype

Protease-activated receptor-1 (PAR-1) is a unique G-protein-coupled receptor belonging to the protease-activated receptor family. Its activation leads to downstream signaling events that launch a variety of cellular responses related to tumor progression. PAR-1 expression has been associated to a variety of human cancers, and our previous studies reveal a high PAR-1 expression in melanoma specimens as compared to common nevi. In the present study, we investigated the contribution of PAR-1 to the malignant phenotype of human melanoma cell lines obtained from cutaneous primary lesions, capable of different metastatic behaviors in the patients from which they have been derived. We found that melanoma cells isolated from lesions giving rise to metastases in patients (WM115, WM278A, WM1361A, WM983A), had higher PAR-1 mRNA and protein expression, as compared to those obtained from lesions that did not develop metastatic disease (WM793, WM35). The cells isolated from metastatic primary lesions were able to colonize the lungs of immunodeficient SCID mice while those isolated from non-metastatic lesions were not. Additionally, cells expressing elevated PAR-1 had higher migratory and invasive abilities than those holding minimal PAR-1 expression. The migration and invasion capabilities of the melanoma cells expressing high PAR-1 were hampered by genetic and pharmacological interventions. The reduction of PAR-1 expression by siRNA and the inhibition of PAR-1 function by the SCH79797 specific antagonist significantly decreased the melanoma cell motility and invasiveness, down to an extent similar to that of the non-metastatic and low PAR-1 expressing cells. Our results provide strong evidence supporting the implication of PAR-1 in the malignant progression of human melanoma.

Identification of a functional role for the protease-activated receptor-1 in hypoxic breast cancer cells

Aberrant expression of the protease-activated receptor (PAR)-1 has been associated with tumour progression. Indeed, PAR-1 expression correlates with tumour invasiveness, as well as with cancer cell survival. As the tumour microenvironment is characterised by a low oxygen tension, we decided to investigate the role of PAR-1 in cancer cells exposed to a hypoxic microenvironment. In this study we show that hypoxia enhances PAR-1 expression in MDAMB231 breast cancer cells. We next provided evidence for a novel role of PAR-1 in protecting hypoxic breast cancer against cell death, since inhibition of PAR-1 by RNA interference resulted in a decreased cell survival. Finally, we found that treatment of hypoxic MDAMB231 cells with the specific PAR-1 agonist peptide (TRAP) resulted in a significant increase of cell survival and migration. The overall results identify for the first time a functional role for PAR-1 in the cellular responses of breast cancer to a hypoxic microenvironment.

Mutational analysis of human BAFF receptor TNFRSF13C (BAFF-R) in patients with common variable immunodeficiency

BAFF receptor (BAFF-R/BR3/TNFRSF13C) is a recently identified molecule that specifically binds BLyS, a protein belonging to the tumor necrosis factor (TNF) family, and is involved in survival and maturation of B cells. Recent studies have demonstrated that mice defective in BAFF-R gene exhibit an altered profile of the B cell pool, a phenotype observed in BLyS knockout mice as well. These features suggest that mutations in this gene may result in humoral immunodeficiency. To test this hypothesis, we sequenced the BAFF-R gene in 48 patients with common variable immunodeficiency (CVID) along with 57 healthy controls. We have identified three novel variants present at the heterozygous state leading to amino acid substitutions, and have also confirmed the existence of a previously reported intronic variant. The hereby described novel variants were also present in healthy controls and in the healthy patients' parents. These variants do not affect the expression of BAFF-R neither at the mRNA nor at the protein level, suggesting that these variants represent novel polymorphic variants of the BAFF-R gene.

A novel activation-induced cytidine deaminase gene mutation in a Tunisian family with hyper IgM syndrome

Mutations in activation-induced cytidine deaminase can cause an autosomal recessive form of hyper-IgM syndrome. We have examined a Tunisian family composed of six members: two healthy parents, their two healthy daughters and two affected sons. We found a homozygous transversion G to T in the two sons while heterozygosity for the mutation was found in all other family members. This alteration is localised in intron 2 at the +1 position resulting in defective splicing. Use of various intronic cryptic splice-sites led to expression of various aberrant mRNA species.

CONCLUSION

This is a novel mutation found in the gene encoding for activation-induced cytidine deaminase in a Tunisian family with hyper-IgM type 2 syndrome. This alteration leads to the use of two cryptic splicing sites causing the formation of two different mRNA species.