Nanomedicine for respiratory diseases

The clinical path to deliver encapsulated phages and lysins

The global emergence of multidrug-resistant pathogens is shaping the current dogma regarding the use of antibiotherapy. Many bacteria have evolved to become resistant to conventional antibiotherapy, representing a health and economic burden for those afflicted. The search for alternative and complementary therapeutic approaches has intensified and revived phage therapy. In recent decades, the exogenous use of lysins, encoded in phage genomes, has shown encouraging effectiveness. These two antimicrobial agents reduce bacterial populations; however, many barriers challenge their prompt delivery at the infection site. Encapsulation in delivery vehicles provides targeted therapy with a controlled compound delivery, surpassing chemical, physical and immunological barriers that can inactivate and eliminate them. This review explores phages and lysins' current use to resolve bacterial infections in the respiratory, digestive, and integumentary systems. We also highlight the different challenges they face in each of the three systems and discuss the advances towards a more expansive use of delivery vehicles.

Iron-Based Core-Shell Nanowires for Combinatorial Drug Delivery and Photothermal and Magnetic Therapy

Combining different therapies into a single nanomaterial platform is a promising approach for achieving more efficient, less invasive, and personalized treatments. Here, we report on the development of such a platform by utilizing nanowires with an iron core and iron oxide shell as drug carriers and exploiting their optical and magnetic properties. The iron core has a large magnetization, which provides the foundation for low-power magnetic manipulation and magnetomechanical treatment. The iron oxide shell enables functionalization with doxorubicin through a pH-sensitive linker, providing selective intracellular drug delivery. Combined, the core-shell nanostructure features an enhanced light-matter interaction in the near-infrared region, resulting in a high photothermal conversion efficiency of >80% for effective photothermal treatment. Applied to cancer cells, the collective effect of the three modalities results in an extremely efficient treatment with nearly complete cell death (∼90%). In combination with the possibility of guidance and detection, this platform provides powerful tools for the development of advanced treatments.

Nanomedicine for drug delivery in South Africa: a protocol for systematic review

BACKGROUND

The emergence of nanomedicine in the past decade has changed the landscape of disease diagnosis and treatment. Nanomedicine makes use of nanostructures for applications in different fields of medicine, including drug delivery, biosensors, neuro-electronic interfaces, in vivo imaging, and cell-specific molecular interactions. Despite its relative infancy, nanomedicine has generated a significant body of research as evidenced by peer reviewed literature and several patents. This proposed systematic review will focus specifically on drug delivery systems in which nanoparticles are used to enhance the pharmacological and therapeutic properties of drugs. The strength of nanoparticulate drug delivery systems is their ability to alter the pharmacokinetics and bio-distribution of drugs. Globally, the discourse on nanomedicine is dominated by research being done in the developed countries of Europe and in the United States of America. Less attention has been given to the applications of nanomedicine in developing countries, particularly Africa. There is dearth of information on the applications of nanomedicine in terms of drug delivery with particular reference to which diseases are being targeted generally in Africa. The review will describe the specific diseases that are being targeted and the progress being made in South Africa, with a view to determining whether the applications of nanomedicine are being appropriated to address the context-specific challenges in this country or if they mimic what is being done globally.

METHODS

Keywords related to nanomedicine and drug delivery will be combined to build a search strategy for each of the following databases: PubMed, Cochrane Library (including Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews, Cochrane Methodology Register), Google Scholar, NHS Health Technology Assessment Database and Web of Science. We will also check reference lists of included studies for other eligible reports and search unpublished data. To ensure that the search is comprehensive, grey literature will be searched extensively. Literature to be included will have nanomedicine in drug delivery as the primary application and report on the specific diseases that are targeted in South Africa. Two authors will independently screen the search output, select studies and extract data; discrepancies will be resolved by consensus and discussion. When no consensus is reached, the third author will be consulted DISCUSSION: The systematic review will inform the government, policy-makers, investors, health professionals, scientists, and engineers about the applications of nanomedicine in drug delivery. In particular, it will identify the diseases targeted by the application of nanomedicine for drug delivery and the progress being made in South Africa as the disease burden of this country differs from that of developed countries where nanomedicine has been widely used for drug delivery.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017057388.

Cytokine-Induced Killer Cells As Pharmacological Tools for Cancer Immunotherapy

Cytokine-induced killer (CIK) cells are a heterogeneous population of effector CD3⁺CD56⁺ natural killer T cells, which can be easily expanded in vitro from peripheral blood mononuclear cells. CIK cells work as pharmacological tools for cancer immunotherapy as they exhibit MHC-unrestricted, safe, and effective antitumor activity. Much effort has been made to improve CIK cells cytotoxicity and treatments of CIK cells combined with other antitumor therapies are applied. This review summarizes some strategies, including the combination of CIK with additional cytokines, dendritic cells, check point inhibitors, antibodies, chemotherapeutic agents, nanomedicines, and engineering CIK cells with a chimeric antigen receptor. Furthermore, we briefly sum up the clinical trials on CIK cells and compare the effect of clinical CIK therapy with other immunotherapies. Finally, further research is needed to clarify the pharmacological mechanism of CIK and provide evidence to formulate uniform culturing criteria for CIK expansion.

Functionalized magnetic nanowires for chemical and magneto-mechanical induction of cancer cell death

Exploiting and combining different properties of nanomaterials is considered a potential route for next generation cancer therapies. Magnetic nanowires (NWs) have shown good biocompatibility and a high level of cellular internalization. We induced cancer cell death by combining the chemotherapeutic effect of doxorubicin (DOX)-functionalized iron NWs with the mechanical disturbance under a low frequency alternating magnetic field. (3-aminopropyl)triethoxysilane (APTES) and bovine serum albumin (BSA) were separately used for coating NWs allowing further functionalization with DOX. Internalization was assessed for both formulations by confocal reflection microscopy and inductively coupled plasma-mass spectrometry. From confocal analysis, BSA formulations demonstrated higher internalization and less agglomeration. The functionalized NWs generated a comparable cytotoxic effect in breast cancer cells in a DOX concentration-dependent manner, (~60% at the highest concentration tested) that was significantly different from the effect produced by free DOX and non-functionalized NWs formulations. A synergistic cytotoxic effect is obtained when a magnetic field (1 mT, 10 Hz) is applied to cells treated with DOX-functionalized BSA or APTES-coated NWs, (~70% at the highest concentration). In summary, a bimodal method for cancer cell destruction was developed by the conjugation of the magneto-mechanical properties of iron NWs with the effect of DOX producing better results than the individual effects.

Carbon Nanomaterials Interfacing with Neurons: An In vivo Perspective

Developing new tools that outperform current state of the art technologies for imaging, drug delivery or electrical sensing in neuronal tissues is one of the great challenges in neurosciences. Investigations into the potential use of carbon nanomaterials for such applications started about two decades ago. Since then, numerous in vitro studies have examined interactions between these nanomaterials and neurons, either by evaluating their compatibility, as vectors for drug delivery, or for their potential use in electric activity sensing and manipulation. The results obtained indicate that carbon nanomaterials may be suitable for medical therapies. However, a relatively small number of in vivo studies have been carried out to date. In order to facilitate the transformation of carbon nanomaterial into practical neurobiomedical applications, it is essential to identify and highlight in the existing literature the strengths and weakness that different carbon nanomaterials have displayed when probed in vivo. Unfortunately the current literature is sometimes sparse and confusing. To offer a clearer picture of the in vivo studies on carbon nanomaterials in the central nervous system, we provide a systematic and critical review. Hereby we identify properties and behavior of carbon nanomaterials in vivo inside the neural tissues, and we examine key achievements and potentially problematic toxicological issues.

Nanomedicine: Past, present and future - A global perspective

Nanomedicine is an emerging and rapidly evolving field and includes the use of nanoparticles for diagnosis and therapy of a variety of diseases, as well as in regenerative medicine. In this mini-review, leaders in the field from around the globe provide a personal perspective on the development of nanomedicine. The focus lies on the translation from research to development and the innovation supply chain, as well as the current status of nanomedicine in industry. The role of academic professional societies and the importance of government funding are discussed. Nanomedicine to combat infectious diseases of poverty is highlighted along with other pertinent examples of recent breakthroughs in nanomedicine. Taken together, this review provides a unique and global perspective on the emerging field of nanomedicine.

Dual-function theranostic nanoparticles for drug delivery and medical imaging contrast: perspectives and challenges for use in lung diseases

Theranostic nanoparticles with both therapeutic and imaging abilities have the promise to revolutionize diagnosis, therapy, and prognosis. Early and accurate detection along with swift treatment are the most important steps in the successful treatment of any disease. Over the last decade, a variety of nanotechnology-based platforms have been created in the hope of improving the treatment and diagnosis of a wide variety of diseases. However, significant hurdles still remain before theranostic nanoparticles can bring clinical solutions to the fight against chronic respiratory diseases. Some fundamental issues such as long-term toxicity, a precise understanding of the accumulation, degradation and clearance of these particles, and the correlation between basic physicochemical properties of these nanoparticles and their in vivo behavior have to be fully understood before they can be used clinically. To date, very little theranostic nanoparticle research has focused on the treatment and diagnosis of chronic respiratory illnesses. Nanomedicine approaches incorporating these theranostic nanoparticles could potentially be translated into clinical advances to improve diagnosis and treatment of these chronic respiratory diseases and enhance quality of life for the patients.

Nanoparticles labeled with positron emitting nuclides: advantages, methods, and applications

Over the past decade, positron emitter labeled nanoparticles have been widely used in and substantially improved for a range of diagnostic biomedical research. However, given growing interest in personalized medicine and translational research, a major challenge in the field will be to develop disease-specific nanoprobes with facile and robust radiolabeling strategies and that provide imaging stability, enhanced sensitivity for disease early stage detection, optimized in vivo pharmacokinetics for reduced nonspecific organ uptake, and improved targeting for elevated efficacy. This review briefly summarizes the major applications of nanoparticles labeled with positron emitters for cardiovascular imaging, lung diagnosis, and tumor theranostics.

Magnetic nanoparticles: an update of application for drug delivery and possible toxic effects

Magnetic nanoparticles (MNPs) represent a subclass within the overall category of nanomaterials and are widely used in many applications, particularly in the biomedical sciences such as targeted delivery of drugs or genes, in magnetic resonance imaging, and in hyperthermia (treating tumors with heat). Although the potential benefits of MNPs are considerable, there is a distinct need to identify any potential toxicity associated with these MNPs. The potential of MNPs in drug delivery stems from the intrinsic properties of the magnetic core combined with their drug loading capability and the biomedical properties of MNPs generated by different surface coatings. These surface modifications alter the particokinetics and toxicity of MNPs by changing protein-MNP or cell-MNP interactions. This review contains current advances in MNPs for drug delivery and their possible organ toxicities associated with disturbance in body iron homeostasis. The importance of protein-MNP interactions and various safety considerations relating to MNP exposure are also addressed.

Antileishmanial effect of silver nanoparticles and their enhanced antiparasitic activity under ultraviolet light

Leishmaniasis is a protozoan vector-borne disease and is one of the biggest health problems of the world. Antileishmanial drugs have disadvantages such as toxicity and the recent development of resistance. One of the best-known mechanisms of the antibacterial effects of silver nanoparticles (Ag-NPs) is the production of reactive oxygen species to which Leishmania parasites are very sensitive. So far no information about the effects of Ag-NPs on Leishmania tropica parasites, the causative agent of leishmaniasis, exists in the literature. The aim of this study was to investigate the effects of Ag-NPs on biological parameters of L. tropica such as morphology, metabolic activity, proliferation, infectivity, and survival in host cells, in vitro. Consequently, parasite morphology and infectivity were impaired in comparison with the control. Also, enhanced effects of Ag-NPs were demonstrated on the morphology and infectivity of parasites under ultraviolet (UV) light. Ag-NPs demonstrated significant antileishmanial effects by inhibiting the proliferation and metabolic activity of promastigotes by 1.5- to threefold, respectively, in the dark, and 2- to 6.5-fold, respectively, under UV light. Of note, Ag-NPs inhibited the survival of amastigotes in host cells, and this effect was more significant in the presence of UV light. Thus, for the first time the antileishmanial effects of Ag-NPs on L. tropica parasites were demonstrated along with the enhanced antimicrobial activity of Ag-NPs under UV light. Determination of the antileishmanial effects of Ag-NPs is very important for the further development of new compounds containing nanoparticles in leishmaniasis treatment.

Informatics and standards for nanomedicine technology

There are several issues to be addressed concerning the management and effective use of information (or data), generated from nanotechnology studies in biomedical research and medicine. These data are large in volume, diverse in content, and are beset with gaps and ambiguities in the description and characterization of nanomaterials. In this work, we have reviewed three areas of nanomedicine informatics: information resources; taxonomies, controlled vocabularies, and ontologies; and information standards. Informatics methods and standards in each of these areas are critical for enabling collaboration; data sharing; unambiguous representation and interpretation of data; semantic (meaningful) search and integration of data; and for ensuring data quality, reliability, and reproducibility. In particular, we have considered four types of information standards in this article, which are standard characterization protocols, common terminology standards, minimum information standards, and standard data communication (exchange) formats. Currently, because of gaps and ambiguities in the data, it is also difficult to apply computational methods and machine learning techniques to analyze, interpret, and recognize patterns in data that are high dimensional in nature, and also to relate variations in nanomaterial properties to variations in their chemical composition, synthesis, characterization protocols, and so on. Progress toward resolving the issues of information management in nanomedicine using informatics methods and standards discussed in this article will be essential to the rapidly growing field of nanomedicine informatics.

Simulated environmental risk estimation of engineered nanomaterials: A case of cosmetics in Johannesburg City

This paper attempts to quantify the potential risks posed by engineered nanomaterials (ENMs) to the aquatic and terrestrial ecosystems from cosmetic-based nanoproducts. The predicted environmental concentrations (PEC) were modelled for the silver (nAg) and titanium dioxide (nTiO2) nanoparticles embedded in cosmetic nanoproducts. The Johannesburg Metropolitan City (JHB City), in South Africa, was used as the reference study area. A mathematical model was applied to compute the quantities of ENMs flows from the cosmetic nanoproducts into the JHB City aquatic and terrestrial ecosystems. The risk quotient (RQ) of the nanoscale materials were evaluated as a ratio of PEC to the predicted no effect concentrations (PNEC). RQ values showed wide variance due to factors like; the quantities of ENMs, the fate and pathways of ENMs in the aquatic and terrestrial ecosystems, efficiency of the wastewater treatment plants (WWTP) as well as the economic and demographic data for South Africa and Switzerland. For the aquatic environment, the PEC values of nAg ranged from 2.80 × 10−3 to 6.19 × 10−1 μg L−1 whereas for nTiO2 the values ranged from 2.7 0 × 10−3 to 2.70 × 10−1 μg L−1 under the realistic dilution factor of 1 with the WWTP functioning at high removal efficiency regime. The RQ values in the aquatic ecosystems were mostly >1, indicating the potential risk of both nAg and nTiO2 but <<<1 in the terrestrial ecosystems. Our results provide the first quantification of ENMs potential risk into the environment Johannesburg City in a developing country’s natural and technical settings.

Human primary bronchial lung cell constructs: the new respiratory models

Scientists routinely work within the three R's principles of 'Reduction, Refinement and Replacement' of animal experiments. Accordingly, viable alternatives are regularly developed, and in the specific case of the human lung, in vitro models for inhalation toxicology that mimic in vivo toxic events that may occur in the human lung, are welcomed. This is especially warranted given the new EU regulations (i.e. REACH) coming into force for the handling of chemicals and the advent of nanotoxicology. Furthermore, recent advances in human tissue-engineering has made it feasible and cost effective to construct human tissue equivalents of the respiratory epithelia, as in-house models derived from primary cells. There is an urgent need for engineered tissue equivalents of the lung given the increase in pharmaceutically valuable drugs, toxicity testing of environmental pollutants and the advent of nanotoxicology. Given the well-known problems with 2-dimensional (2-D) cell cultures as test beds, more realistic 3-D tissue constructs are required, especially for preclinical stages of cell- and tissue-based, high-throughput screening in drug discovery. The generation of high-fidelity engineered tissue constructs is based on the targeted interactions of organ-specific cells and intelligent biomimetic scaffolds which emulate the natural environment of their native extracellular matrix, in which the cells develop, differentiate and function. The proximal region of the human respiratory system is a critical zone to recapitulate for use as in vitro alternatives to in vivo inhalation toxicology. Undifferentiated normal human bronchial epithelia cells can be obtained from surgical procedures or purchased from commercial sources and used to establish 3-D, differentiated, organo-typic cell cultures for pulmonary research.