Pulmonary challenge with carbon nanoparticles induces a dose-dependent increase in circulating leukocytes in healthy males

Immunomodulatory and immune-toxicological role of nanoparticles: Potential therapeutic applications

Nowadays, Nanoparticle-based immunotherapeutic research has invoked global interest due to their unique properties. The immune system is a shielding structure that defends living things from external threats. Before the use of any materials in drug design, it is essential to study the immunological response to avoid triggering undesirable immune responses in the body. This review tries to summarize the properties, various applications, and immunotherapeutic aspects of NP-induced immunomodulation relating to therapeutic development and toxicity in human health. The role of NPs in the immune system and their modulatory functions, resulting in immunosuppression or immunostimulation, exerts benefits or dangers depending on their compositions, sizes, surface chemistry, and so forth. After NPs enter into the body, they can interact with body fluid exposing, them to different body proteins to form protein corona particles and other bio-molecules (DNA, RNA, sugars, etc.), which may alter their bioactivity. Phagocytes are the first immune cells that can interact with foreign materials including nanoparticles. Immunostimulation and immunosuppression operate in two distinct manners. Overall, functionalized nanocarriers optimized various therapeutic implications by stimulating the host immune system and regulating the tranquility of the host immune system. Among others, toxicity and bio-clearance of nanomaterials are always prime concerns at the preclinical and clinical stages before final approval. The interaction of nanoparticles with immune cells causes direct cell damage via apoptosis and necroses as well as immune signaling pathways also become influenced.

Carbon nanoparticles adversely affect CFTR expression and toxicologically relevant pathways

Cystic fibrosis is an autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) that can lead to terminal respiratory failure. Ultrafine carbonaceous particles, which are ubiquitous in ambient urban and indoor air, are increasingly considered as major contributors to the global health burden of air pollution. However, their effects on the expression of CFTR and associated genes in lung epithelial cells have not yet been investigated. We therefore evaluated the effects of carbon nanoparticles (CNP), generated by spark-ablation, on the human bronchial epithelial cell line 16HBE14o- at air-liquid interface (ALI) culture conditions. The ALI-cultured cells exhibited epithelial barrier integrity and increased CFTR expression. Following a 4-h exposure to CNP, the cells exhibited a decreased barrier integrity, as well as decreased expression of CFTR transcript and protein levels. Furthermore, transcriptomic analysis revealed that the CNP-exposed cells showed signs of oxidative stress, apoptosis and DNA damage. In conclusion, this study describes spark-ablated carbon nanoparticles in a realistic exposure of aerosols to decrease CFTR expression accompanied by transcriptomic signs of oxidative stress, apoptosis and DNA damage.

Immunotoxicity of Carbon-Based Nanomaterials, Starring Phagocytes

In the field of science, technology and medicine, carbon-based nanomaterials and nanoparticles (CNMs) are becoming attractive nanomaterials that are increasingly used. However, it is important to acknowledge the risk of nanotoxicity that comes with the widespread use of CNMs. CNMs can enter the body via inhalation, ingestion, intravenously or by any other route, spread through the bloodstream and penetrate tissues where (in both compartments) they interact with components of the immune system. Like invading pathogens, CNMs can be recognized by large numbers of receptors that are present on the surface of innate immune cells, notably monocytes and macrophages. Depending on the physicochemical properties of CNMs, i.e., shape, size, or adsorbed contamination, phagocytes try to engulf and process CNMs, which might induce pro/anti-inflammatory response or lead to modulation and disruption of basic immune activity. This review focuses on existing data on the immunotoxic potential of CNMs, particularly in professional phagocytes, as they play a central role in processing and eliminating foreign particles. The results of immunotoxic studies are also described in the context of the entry routes, impacts of contamination and means of possible elimination. Mechanisms of proinflammatory effect depending on endocytosis and intracellular distribution of CNMs are highlighted as well.

Concentration-dependent health effects of air pollution in controlled human exposures

BACKGROUND

Air pollution is a leading contributor to premature mortality worldwide and is often represented by particulate matter (PM), a key contributor to its harmful health effects. Concentration-response relationships are useful for quantifying the effects of air pollution in relevant populations and in considering potential effect thresholds. Controlled human exposures can provide data on acute effects and concentration-response relationships that complement epidemiological studies.

OBJECTIVES

We examined PM concentration-responses after controlled human air pollution exposures to examine exposure-response markers, assess effect modifiers, and identify potential effect thresholds.

METHODS

We reviewed primary research from published controlled human exposure studies where responses were reported at multiple target PM concentrations or summarized per unit change in PM to identify concentration-dependent effects.

RESULTS

Of the 191 publications identified through PubMed and supplementary searches, 31 were eligible. Eligible studies collectively represented four pollutant models: concentrated ambient particles, engineered carbon nanoparticles, diesel exhaust, and woodsmoke. We identified concentration-dependent effects on oxidative stress markers, inflammation, and cardiovascular function that overlapped across different pollutants. Metabolic syndrome and glutathione s-transferase mu 1 genotype were identified as potential effect modifiers.

DISCUSSION

Improved understanding of concentration-response relationships is integral to biomonitoring and mitigation of health effects through impact assessment and policy. Although we identified potential concentration-response markers, thresholds, and modifiers, our conclusions on these relationships were limited by a dearth of eligible publications, considerable variability in methodology, and inconsistent reporting standards between studies. More research is required to validate these observations. We recommend that future studies harmonize estimate reporting to facilitate the identification of robust response markers across research and applied settings.