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Metal-Based Nanoparticles and the Immune System: Activation, Inflammation, and Potential Applications
Published in Raj Bawa, János Szebeni, Thomas J. Webster, Gerald F. Audette, Immune Aspects of Biopharmaceuticals and Nanomedicines, 2019
Yueh-Hsia Luo, Louis W. Chang, Pinpin Lin
Mast cells contain many granules in histamine and heparin and have important roles of allergy and anaphylaxis. When activated, mast cells rapidly release histamine and heparin from their granules to dilate blood vessels and recruit neutrophils and macrophages. Chen et al. demonstrated that TiO2 nanoparticles not only dose-dependently increased histamine secretion, but also increased cytosolic Ca2+ concentration in rat mast cells [93]. Their results suggest that systemic circulation of nanoparticles may prompt histamine release without prior allergen sensitization, causing abnormal inflammatory diseases or potential exacerbating manifestations of multiple allergic responses. It was recently reported that the granules of mast cells are powerful enhancers of adaptive immunity when they are released at sites of infection or vaccine administration. John et al. engineered nanoparticles consisting of mast cell granules to augment immunity during vaccination [94]. It is believed that other metal-based nanoparticles also have the possibility of developing this efficient vaccination system.
Cellular and Molecular Basis of Human Biology
Published in Lawrence S. Chan, William C. Tang, Engineering-Medicine, 2019
Mast Cells. Clearly identified by its basophilic cytoplasmic granules, mast cells are local residents on the skin. They possess a special antibody receptor on their surface that accept immunoglobulin E (IgE). The binding of IgE to IgE receptor on mast cells will trigger release of histamines and other inflammatory cytokines. The presence of large amount of mast cells indicate an allergic type of reaction.
Homo Sapiens (“Us”): Strengths and Weaknesses
Published in Michael Hehenberger, Zhi Xia, Huanming Yang, Our Animal Connection, 2020
Michael Hehenberger, Zhi Xia, Huanming Yang
Neurotransmitters are chemical messengers that transmit signals across a synapse, such as a neuromuscular junction, from one neuron to another “target” neuron, muscle cell, or gland cell of the endocrine system. Examples of neurotransmitters are listed below: Glutamate is used at the great majority of fast synapses in the brain and spinal cord. Excessive glutamate release can overstimulate the brain and lead to excitotoxicity causing cell death resulting in seizures or strokes. Excitotoxicity has been implicated in certain chronic diseases, including ischemic stroke, epilepsy, amyotrophic lateral sclerosis, Alzheimer’s disease, Huntington disease, and Parkinson’s disease.46GABA (γ-aminobutyric acid) is used at the great majority of fast inhibitory synapses in virtually every part of the brain. Many sedative/tranquilizing drugs act by enhancing the effects of GABA.Acetylcholine was the first neurotransmitter discovered in the peripheral and central nervous systems. It is distinguished as the transmitter at the neuromuscular junction connecting motor nerves to muscles.Dopamine is playing a number of important functions in the brain. Dopamine regulates motor behavior and is related to pleasure as well as motivation. It plays a critical role in the reward system.Serotonin is a monoamine neurotransmitter. It is an interesting fact that 90% of serotonin is produced by, and found in the intestine. Serotonin also plays important roles in central nervous system neurons, regulating appetite, sleep, memory and learning, temperature, mood, behavior, muscle contraction, and function of the cardiovascular system and endocrine system. It may also play a role in depression.Norepinephrine is synthesized (from tyrosine) in the central nervous system and modulates the responses of the autonomic nervous system, the sleep patterns, focus and alertness.Epinephrine is also synthesized from tyrosine and released in the adrenal glands and the brainstem. It plays a role in sleep, influences the ability to be and stay alert, and the “fight-or-flight” response.Histamine works with the central nervous system (CNS), specifically the hypothalamus and CNS mast cells. Mast cells are a type of white blood cell, best known for their role in allergy and in important protective roles such as wound healing, angiogenesis (formation of new blood vessels), immune tolerance, and defense against pathogens.
Prednisolone-loaded coatable polyvinyl alcohol/alginate hydrogel for the treatment of atopic dermatitis
Published in Journal of Biomaterials Science, Polymer Edition, 2018
Hye Ri Lee, Tae Ho Kim, Se Heang Oh, Jin Ho Lee
To examine mast cell infiltration in the skin, the skin tissue sections of each group were also stained with Toluidine blue (Figure 8(a)) and the number of mast cells were counted (Figure 8(b)). Histamine is a major constituent of mast cells and its release from the mast cells is closely related with increased tissue erythema and various allergic reactions [37]. The skin of the Control group showed that the infiltrated mast cells markedly increased compared with the Normal group, but the number of mast cells in the PS sol’n and PS-loaded hydrogel groups notably decreased than the Control group. The number of infiltrated mast cell in the skin is as follows: Control (97.8 ± 20.1 cells/mm2) > PS-free hydrogel (81.0 ± 6.5 cells/mm2) > PS sol’n (60.0 ± 4.6 cells/mm2) > PS-loaded hydrogel (42.5 ± 4.0 cells/mm2) > normal (14.3 ± 3.5 cells/mm2). On the basis of our findings, we can suggest that the PS-loaded PVA/ALG hydrogel may be a promising candidate for the treatment of the AD.
Correlation between mast cell-mediated allergic inflammation and length of perfluorinated compounds
Published in Journal of Toxicology and Environmental Health, Part A, 2018
Allergic inflammation is an abnormal reaction of the body evidenced as over-reaction of the immune system (Hainsworth 2003). Mast cells are known to play a key role in allergic inflammation, and release various inflammatory mediators, including histamine, cytokines, chemokines, and proteases (Amin 2012). Histamine is released by the degranulation of mast cells and is one of the predominant mediators leading to immediate-type hypersensitivity (Amin 2012). Mast cell degranulation is induced by calcium (Ca) mobilization through granule membrane fusion (Nishida et al. 2005). Subsequently, this induces activation of transcription factor nuclear factor (NF)-κB and release of inflammatory cytokines and chemokines (Liu et al. 2017). NF-κB regulates expression of pro-inflammatory cytokines and chemokines known to produce increased vascular permeability, inflammation, and tissue remodeling (Kempe et al. 2005).