Multiple Sclerosis: LIFNano-CD4 for Trojan Horse Delivery of the Neuro-Protective Biologic "LIF" Into the Brain: Preclinical Proof of Concept.

Multiple sclerosis (MS) is a demyelinating autoimmune disease that attacks the brain, with year-on-year loss of brain volume, starting late teens and becoming manifest late twenties. There is no cure, and current therapies are immunosuppressive only. LIF is a vital stem cell growth factor active throughout life-and essential for health of the central nervous system (CNS), being tolerogenic, myelinogenic, and neuroprotective. Nano-formulation of LIF (LIFNano) using FDA-approved PLGA captures LIF's compound therapeutic properties, increasing potency 1,000-fold when targeted to CD4 (LIFNano-CD4). Moreover, circulating CD4+ lymphocytes are themselves regulated by LIF to express the Treg phenotype, known to release T cell-derived LIF upon engagement with cognate antigen, perpetuating antigen-specific self-tolerance. With the longer-term aim of treating inflammatory lesions of MS, we asked, does LIFNano-CD4 cross the blood-brain barrier (BBB)? We measure pK and pD using novel methodologies, demonstrate crossing of the BBB, show LIF-cargo-specific anti-inflammatory efficacy in the frontal cortex of the brain, and show safety of intravenous delivery of LIFNano-CD4 at doses known to provide efficacious concentrations of LIF cargo behind the BBB.

Delivering the power of nanomedicine to patients today.

The situation of the COVID-19 pandemic reminds us that we permanently need high-value flexible solutions to urgent clinical needs including simplified diagnostic technologies suitable for use in the field and for delivering targeted therapeutics. From our perspective nanotechnology is revealed as a vital resource for this, as a generic platform of technical solutions to tackle complex medical challenges. It is towards this perspective and focusing on nanomedicine that we take issue with Prof Park's recent editorial published in the Journal of Controlled Release. Prof. Park argued that in the last 15 years nanomedicine failed to deliver the promised innovative clinical solutions to the patients (Park, K. The beginning of the end of the nanomedicine hype. Journal of Controlled Release, 2019; 305, 221-222 [1]. We, the ETPN (European Technology Platform on Nanomedicine) [2], respectfully disagree. In fact, the more than 50 formulations currently in the market, and the recent approval of 3 key nanomedicine products (e. g. Onpattro, Hensify and Vyxeos), have demonstrated that the nanomedicine field is concretely able to design products that overcome critical barriers in conventional medicine in a unique manner, but also to deliver within the cells new drug-free therapeutic effects by using pure physical modes of action, and therefore make a difference in patients lives. Furthermore, the >400 nanomedicine formulations currently in clinical trials are expecting to bring novel clinical solutions (e.g. platforms for nucleic acid delivery), alone or in combination with other key enabling technologies to the market, including biotechnologies, microfluidics, advanced materials, biomaterials, smart systems, photonics, robotics, textiles, Big Data and ICT (information & communication technologies) more generally. However, we agree with Prof. Park that " it is time to examine the sources of difficulty in clinical translation of nanomedicine and move forward ". But for reaching this goal, the investments to support clinical translation of promising nanomedicine formulations should increase, not decrease. As recently encouraged by EMA in its roadmap to 2025, we should create more unity through a common knowledge hub linking academia, industry, healthcare providers and hopefully policy makers to reduce the current fragmentation of the standardization and regulatory body landscape. We should also promote a strategy of cross-technology innovation, support nanomedicine development as a high value and low-cost solution to answer unmet medical needs and help the most promising innovative projects of the field to get better and faster to the clinic. This global vision is the one that the ETPN chose to encourage for the last fifteen years. All actions should be taken with a clear clinical view in mind, " without any fanfare", to focus "on what matters in real life", which is the patient and his/her quality of life. This ETPN overview of achievements in nanomedicine serves to reinforce our drive towards further expanding and growing the maturity of nanomedicine for global healthcare, accelerating the pace of transformation of its great potential into tangible medical breakthroughs.

Mesenchymal stem cells and management of COVID-19 pneumonia.

Human coronavirus, hCoV-19, is highly pathogenic with severe pneumonia associated with rapid virus replication. Arising in Wuhan China December 2019, the current COVID-19 epidemic has rapidly grown with person-to-person infection expanding to become a global health emergency now on pandemic scale. Governments will not be able to minimise both deaths from COVID-19 and the economic impact of viral spread in mitigation of this current COVID-19 pandemic, according to Anderson et al. 2020 [1], Keeping mortality as low as possible will be the highest priority for individuals; hence governments must put in place measures to ameliorate the inevitable economic downturn. The current global picture shows small chains of transmission in many countries and large chains resulting in extensive spread in a few countries, such as Italy, Iran, South Korea, and Japan. Most countries are likely to have spread of COVID-19, at least in the early stages, before any mitigation measures have an impact. The scale of the problem is massive. Here I consider new approaches to improve patient's biological resistance to COVID-19 using stem cells, and how benefit might be scaled and simplified using synthetic stem cells to meet logistical needs within a short time frame.

Stereotactic Body Radiotherapy for Lung Metastases from Colorectal Cancer: Prognostic Factors for Disease Control and Survival.

OBJECTIVES: To evaluate disease control and survival after stereotactic body radiotherapy (SBRT) for lung metastases from colorectal cancer and to identify prognostic factors after treatment. METHODS: Patients with metastatic colorectal cancer to the lungs treated with SBRT from 2002 to 2013 were identified from a prospectively maintained database. Patients may have received prior systemic therapy, radiotherapy to nonthoracic sites and/or resection of thoracic and/or nonthoracic metastases. Endpoints were timed from end of SBRT and included overall survival (OS), progression-free survival, distant metastases-free survival, and local failure-free survival. Univariate and multivariate analysis using Cox proportional hazard modeling was used to identify prognostic factors. RESULTS: Sixty-five patients were identified. Before SBRT, 69.2% and 33.8% of patients received systemic therapy and lung-directed local therapy, respectively, for metastatic disease. At the time of SBRT, 64.6% had lung-only involvement. Median survivals were: OS of 20.3 months (95% confidence intervals [CI], 15.9-27.0 mo), progression-free survival of 5.7 months (95% CI, 3.2-7.0 mo), distant metastases-free survival of 5.8 months (95% CI, 3.2-7.6 mo), and local failure-free survival of 15.4 months (95% CI, 8.5-21.1 mo). Nearly all (98%) patients developed distant progression. Extra lung and liver involvement at the time of initial metastases (hazard ratios [HR] 2.10) and extra lung involvement at SBRT (HR 2.67) were the only independent predictors of OS. Net gross target volume of >14.1 mL (HR 2.49) was the only independent predictor of local failure-free survival. CONCLUSIONS: Reasonable survival and local control can be achieved with SBRT. We identified several prognostic factors testable in future prospective trials that may help improve patient selection.

Neurodegenerative Disease: A Perspective on Cell-Based Therapy in the New Era of Cell-Free Nano-Therapy.

Neurodegenerative diseases (NDD) result in irreversible loss of neurons. Dementia develops when disease-induced neuronal loss becomes sufficient to impair both memory and cognitive functioning and, globally, dementia is increasing to epidemic proportions as populations age. In the current era of regenerative medicine intense activity is asking, can loss of endogenous neurons be compensated by replacement with exogenously derived cells that have either direct, or indirect, neurogenic capacity? But, more recently, excitement is growing around an emerging alternative to the cell-based approach - here nanotechnology for targeted delivery of growth factor aims to support and expand resident central nervous system (CNS) stem cells for endogenous repair. The concept of a high volume, off-the-shelf nano-therapeutic able to rejuvenate the endogenous neuroglia of the CNS is highly attractive, providing a simple solution to the complex challenges posed by cell-based regenerative medicine. The role of inflammation as an underlying driver of NDD is also considered where anti-inflammatory approaches are candidates for therapy. Indeed, cell-based therapy and/or nanotherapy may protect against inflammation to support both immune quiescence and neuronal survival in the CNS - key targets for treating NDD with the potential to reduce or even stop the cascading pathogenesis and disease progression, possibly promoting some repair where disease is treated early. By design, nanoparticles can be formulated to cross the blood brain barrier (BBB) enabling sustained delivery of neuro-protective agents for sufficient duration to reset neuro-immune homeostasis. Proven safe and efficacious, it is now urgent to deliver nano-medicine (NanoMed) as a scalable approach to treat NDD, where key stakeholders are the patients and the global economy.

Myelin repair in vivo is increased by targeting oligodendrocyte precursor cells with nanoparticles encapsulating leukaemia inhibitory factor (LIF).

Multiple sclerosis (MS) is a progressive demyelinating disease of the central nervous system (CNS). Many nerve axons are insulated by a myelin sheath and their demyelination not only prevents saltatory electrical signal conduction along the axons but also removes their metabolic support leading to irreversible neurodegeneration, which currently is untreatable. There is much interest in potential therapeutics that promote remyelination and here we explore use of leukaemia inhibitory factor (LIF), a cytokine known to play a key regulatory role in self-tolerant immunity and recently identified as a pro-myelination factor. In this study, we tested a nanoparticle-based strategy for targeted delivery of LIF to oligodendrocyte precursor cells (OPC) to promote their differentiation into mature oligodendrocytes able to repair myelin. Poly(lactic-co-glycolic acid)-based nanoparticles of ∼120 nm diameter were constructed with LIF as cargo (LIF-NP) with surface antibodies against NG-2 chondroitin sulfate proteoglycan, expressed on OPC. In vitro, NG2-targeted LIF-NP bound to OPCs, activated pSTAT-3 signalling and induced OPC differentiation into mature oligodendrocytes. In vivo, using a model of focal CNS demyelination, we show that NG2-targeted LIF-NP increased myelin repair, both at the level of increased number of myelinated axons, and increased thickness of myelin per axon. Potency was high: a single NP dose delivering picomolar quantities of LIF is sufficient to increase remyelination. Impact statement Nanotherapy-based delivery of leukaemia inhibitory factor (LIF) directly to OPCs proved to be highly potent in promoting myelin repair in vivo: this delivery strategy introduces a novel approach to delivering drugs or biologics targeted to myelin repair in diseases such as MS.

Multiple Sclerosis and the LIF/IL-6 Axis: Use of Nanotechnology to Harness the Tolerogenic and Reparative Properties of LIF.

Leukaemia inhibitory factor (LIF) plays a critical role in "stemness" versus "differentiation", a property that underpins the core value of LIF as a therapeutic for both the treatment of autoimmune disease and for promoting tissue repair. This value can be realized using nano-engineering technology, where a new generation of tools can, with unprecedented ability, manipulate biological functions. One striking example is the treatment of multiple sclerosis (MS). The underpinning biology is the newly identified LIF/IL-6 axis in T lymphocytes, which can tilt the behaviour between immune tolerance versus immune attack. This LIF/IL-6 axis is ideally suited to nanotherapeutic manipulation, given its inherent mechanistic simplicity of two mutually opposing feed-forward loops that determine either tolerogenic (LIF) or inflammatory (IL-6) immunity. Using LIF that is formulated in biodegradable nanoparticles (LIF-NP) and targeted to CD4+ T cells, the axis is harnessed towards immune tolerance. This has implications for the treatment of autoimmune diseases, where the clinical burden is immense. It encompasses more than 100 diseases and, in the USA alone, costs more than $100 billion in direct health care costs annually. Other properties of LIF include the promotion of healthy neuro-glial interactions within the central nervous system (CNS), where, in addition to MS, LIF-NP therapy is relevant to inflammatory neurodegenerative diseases that represent a large and increasing need within aging populations. Thirdly, LIF is a reparative growth factor that can maintain genomic plasticity. LIF-NP supports the use of stem cell-based therapies in regenerative medicine plus augment therapeutic benefits within the patient. These core properties of LIF are greatly amplified in value by the advantage of being formulated as nanoparticles, namely (i) targeted delivery, (ii) exploitation of endogenous regulatory pathways and (iii) creation of surrogate micro-stromal niches. We discuss LIF-NP as a means to harness endogenous pathways for the treatment of MS, both to reset immune self-tolerance and to promote repair of myelin that is required to support health within the nervous system.

Modelling of a targeted nanotherapeutic 'stroma' to deliver the cytokine LIF, or XAV939, a potent inhibitor of Wnt-ß-catenin signalling, for use in human fetal dopaminergic grafts in Parkinson's disease.

The endogenous reparative capacity of the adult human brain is low, and chronic neurodegenerative disorders of the central nervous system represent one of the greatest areas of unmet clinical need in the developing world. Novel therapeutic strategies to treat them include: (i) growth factor delivery to boost endogenous repair and (ii) replacement cell therapy, including replacing dopaminergic neurons to treat Parkinson's disease (PD). However, these approaches are restricted not only by rapid degradation of growth factors, but also by the limited availability of cells for transplant and the poor survival of implanted cells that lack the necessary stromal support. We therefore hypothesised that provision of a transient artificial stroma for paracrine delivery of pro-survival factors could overcome both of these issues. Using leukaemia inhibitory factor (LIF) - a proneural, reparative cytokine - formulated as target-specific poly(lactic-co-glycolic acid) (PLGA) nano-particles (LIF-nano-stroma), we discovered that attachment of LIF-nano-stroma to freshly isolated fetal dopaminergic cells improved their survival fourfold: furthermore, in vivo, the number of surviving human fetal dopaminergic cells tended to be higher at 3 months after grafting into the striatum of nude rats, compared with controls treated with empty nanoparticles. In addition, we also analysed the effect of a novel nano-stroma incorporating XAV939 (XAV), a potent inhibitor of the developmentally important Wnt-ß-catenin signalling pathway, to investigate whether it could also promote the survival and differentiation of human fetal dopaminergic precursors; we found that the numbers of both tyrosine-hydroxylase-positive neurons (a marker of dopaminergic neurons) and total neurons were increased. This is the first demonstration that LIF-nano-stroma and XAV-nano-stroma each have pro-survival effects on human dopaminergic neurons, with potential value for target-specific modulation of neurogenic fate in cell-based therapies for PD.