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Osteoimmunomodulation with Biomaterials
Published in Nihal Engin Vrana, Biomaterials and Immune Response, 2018
Bengü Aktaş, Bora Garipcan, Zehra Betül Ahi, Kadriye Tuzlakoğlu, Emre Ergene, Pınar Yılgör Huri
All of these immune cells have distinct precursors and very specific roles in the inflammatory reaction. For example, monocytes are cells formed by precursor cells, called monoblasts, present in the bone marrow. These cells circulate via the bloodstream. During inflammation, monocytes leave the bloodstream and migrate to the tissues. Then, they differentiate into macrophages or dendritic cells under the influence of various growth factors and cytokines within tissues. Tissue macrophages are the first line of the body’s defence mechanism and their primary action is to perform phagocytosis to digest any foreign substance to the body [18]. Granulocytes are a group of white blood cells with small granules in their cytoplasm. There are three different types of granulocytes: neutrophils, eosinophils and basophils. Neutrophils kill the invaders in three different ways: phagocytosis, secretion of soluble antimicrobials and neutrophil extracellular traps (NETs). Eosinophils are very important for fighting against parasitic infections as their granules contain cathepsin, which is a unique toxic protein. Basophils are responsible for immune response during the formation of acute and chronic allergic diseases [19].
Inorganic Chemical Pollutants
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
William J. Rea, Kalpana D. Patel
Inflammatory professionals: Neutrophils, mast cells, and platelets are detectable in lesions and may influence atherosclerosis and its complications in important ways. Neutrophils, the inflammatory granulocytes, circulate in large numbers and accumulate early on at sites of injury or infection. Neutrophils also contain large quantities of myeloperoxidase, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and lipoxygenases, which contribute to oxidative stress, a major determinant of endothelial cell dysfunction, lesion growth, and instability. Mast cells, best known for their role in allergy and anaphylaxis, promote atherosclerosis by releasing the contents of their protease-cytokine-autacoid-rich granules.268 Platelets play an essential, dual role. During atherosclerosis, they adhere to the endothelium and help monocytes enter lesions.269 During plaque rupture, they form the thrombus that causes ischemia of downstream tissue.237 Thus, neutrophils, mast cells, and platelets all promote atherosclerosis by intensifying inflammation.
In Vitro Testing
Published in Julián Blasco, Ilaria Corsi, Ecotoxicology of Nanoparticles in Aquatic Systems, 2019
Alberto Katsumiti, Miren P. Cajaraville
Haemocytes or immunocytes comprise the internal defence system in bivalve molluscs. Haemocytes are also involved in digestion, shell repair, respiration, osmoregulation, transportand excretion (Cheng 1981). In mussels, two main types of haemocytes have been described: granulocytes and agranulocytes or hyalinocytes (Cheng 1981, Cajaraville and Pal 1995, Carballal et al. 1997, 1998). Granulocytes are large cells (10–20 µm in diameter) with a small nucleus, characterised by containing numerous cytoplasmic granules, most of which are lysosomes (Cajaraville and Pal 1995). Granulocytes are the main haemocyte type involved in phagocytosis, intracellular digestion and immune defence (Carballal et al. 1997). Hyalinocytes are agranular small cells (4–6 µm in diameter) that present characteristics of undifferentiated cells: a small volume of cytoplasm that contains few organelles, abundant free ribosomes, and a central large nucleus (Cajaraville and Pal 1995). Although less active than granulocytes, these cells are also involved in phagocytosis, intracellular digestion and immune defence (Cajaraville and Pal 1995, Carballal et al. 1997). Hyalinocytes are probably intermediate forms that give rise to granulocytes, since they seem to have an important role in protein synthesis and the granules contain abundant enzymes (Carballal et al. 1997). Gill cells are epithelial cells responsible for uptake and transport of nutrients, gas exchange and ionic osmoregulation (Owen 1974, 1978, Owen and McCrae 1976). Gill cells are the first target and uptake site of many contaminants in the aquatic environment (Livingstone and Pipe 1992, Gómez-Mendikute et al. 2005).
Computer-aided system for Leukocyte nucleus segmentation and Leukocyte classification based on nucleus characteristics
Published in International Journal of Computers and Applications, 2020
White Blood Cells (WBCs), also termed as Leukocytes provide immunity against diseases and also help in protecting the body against infections. They are produced by the hematopoietic stem cells in the bone marrow. The WBCs are distinguishable from Platelets and Erythrocytes due to the presence of Nucleus. WBCs are broadly classified into Granulocytes and Agranulocytes based on their structure. The broader categories can be further divided into five types namely, Basophil, Neutrophil, Eosinophil, Monocyte, and Lymphocyte. Characterization of WBCs is shown in Table 1.