The preclinical safety assessment of novel nanotechnology-based drug products frequently relies on in vitro assays, especially during the early stages of product development, due to the limited quantities of nanomaterials available for such studies. The majority of immunological tests require donor blood. To enable such tests one has to prevent the blood from coagulating, which is usually achieved by the addition of an anticoagulant into blood collection tubes.
View Article and Find Full Text PDFAutophagy is a catabolic process involved in the degradation and recycling of long-lived proteins and damaged organelles for maintenance of cellular homeostasis, and it has also been proposed as a type II cell death pathway. The cytoplasmic components targeted for catabolism are enclosed in a double-membrane autophagosome that merges with lysosomes, to form autophagosomes, and are finally degraded by lysosomal enzymes. There is substantial evidence that several nanomaterials can cause autophagy and lysosomal dysfunction, either by prevention of autophagolysosome formation, biopersistence or inhibition of lysosomal enzymes.
View Article and Find Full Text PDFCytokines, chemokines, and interferons are released by the immune cells in response to cellular stress, damage and/or pathogens, and are widely used as biomarkers of inflammation. Certain levels of cytokines are needed to stimulate an immune response in applications such as vaccines or immunotherapy where immune stimulation is desired. However, undesirable elevation of cytokine levels, as may occur in response to a drug or a device, may lead to severe side effects such as systemic inflammatory response syndrome or cytokine storm.
View Article and Find Full Text PDFThis chapter provides a protocol for analysis of nanoparticle effects on the function of phagocytic cells. The protocol relies on luminol chemiluminescence to detect zymosan uptake. Zymosan is an yeast particle which is typically eliminated by phagocytic cells via the complement receptor pathway.
View Article and Find Full Text PDFBlood clotting is a complex process which involves both cellular and biochemical components. The key cellular players in the blood clotting process are thrombocytes or platelets. Other cells, including leukocytes and endothelial cells, contribute to clotting by expressing the so-called pro-coagulant activity (PCA) complex on their surface.
View Article and Find Full Text PDFTriazine and PAMAM dendrimers of similar size and number of cationic surface groups were compared for their ability to promote platelet aggregation. Triazine dendrimers (G3, G5 and G7) varied in molecular weight from 8 kDa-130 kDa and in surface groups 16-256. PAMAM dendrimers selected for comparison included G3 (7 kDa, 32 surface groups) and G6 (58 kDa, 256 surface groups).
View Article and Find Full Text PDFAutophagy, a catabolic survival pathway, is gaining attention as a potential target in cancer. In human liver and colon cancer cells, treatment with an autophagy inducer, nanoliposomal C6-ceramide, in combination with the autophagy maturation inhibitor, vinblastine, synergistically enhanced apoptotic cell death. Combination treatment resulted in a marked increase in autophagic vacuole accumulation and decreased autophagy maturation, without diminution of the autophagy flux protein P62.
View Article and Find Full Text PDFAims: Thrombogenicity associated with the induction of leukocyte procoagulant activity (PCA) is a common complication in sepsis and cancer. Since nanoparticles are increasingly used for drug delivery, their interaction with coagulation systems is an important part of the safety assessment. The purpose of this study was to investigate the effects of nanoparticle physicochemical properties on leukocyte PCA, and to get insight into the mechanism of PCA induction.
View Article and Find Full Text PDFLysosomal dysfunction is a recognized toxic mechanism for xenobiotics, which can result in various pathological states. There is concern that nanoparticles, in particular, may cause lysosomal pathologies, since they are likely to accumulate within lysosomes. Dysregulation of the autophagy-lysosomal degradation pathway is an example of lysosomal dysfunction associated with exposure to some nanomaterials.
View Article and Find Full Text PDFThe assessment of psychological morbidity in patients with ALS has centered around depression, hopelessness, and anxiety. The Brief Symptom Inventory (BSI) offers an opportunity to explore psychological morbidity more broadly. We administered this instrument to 111 patients with ALS as part of a larger study of quality of life.
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