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Microfluidic Techniques for High-Throughput Cell Analysis
Published in Hyun Jung Kim, Biomimetic Microengineering, 2020
Dongwei Chen, Juanli Yun, Yuxin Qiao, Jian Wang, Ran Hu, Beiyu Hu, Wenbin Du
Saadi et al. (2007) presented a “Ladder Chamber”, which uses a two-compartment diffusion system to generate steady-state gradients (Figure 7.4a). The chamber consists of two main channels and an array of microchannels that bridge them. Concentration gradients are obtained by diffusion of soluble molecules through collagen gel filled in the microchannels, which provides a 3D environment for cells. Neutrophil migration under chemoattractant (interleukin-8) gradients was observed in the chamber. Mosadegh et al. (2007) further evolved the ladder chamber by changing the geometries of gradient-generating region (Figure 7.4b). Aizel et al. (2017) developed a tunable microfluidic system for chemotaxis studies in a 3D collagen matrix. This microsystem can generate either homogeneous gradients by pure diffusion or spatially evolving gradients by convection diffusion. A stable gradient can be maintained over days for long-duration chemotaxis experiments. Cancer cells migrating along chemokine gradients was observed in this device. Agarose gels are also used as the matrix for mammalian cell chemotaxis in a 3D μFCD (Figure 7.4). In summary, by introducing biomatrices into microfluidic devices to mimic extracellular matrix, these studies which provides more physiologically compatible microenvironments than two-dimensional diffusion chambers for mammalian cell chemotaxis. However, the matrices employed in these studies are far from reflecting in vivo microenvironments, and further innovations are needed to enable more flexible and controllable gradient generation.
Chitosan: A Versatile Biomaterial for the 21st Century
Published in Shakeel Ahmed, Aisverya Soundararajan, Marine Polysaccharides, 2018
A. Shajahan, V. Kaviyarasan, V. Narayanan, S. Ignacimuthu
Healing restores the integrity of the injured tissue and prevents organisms from deregulation of homeostasis. The treatment of wounds has evolved from ancient times. Initially, application of dressing material was aimed at inhibition of bleeding and protection of the wound from environmental irritants as well as water and electrolyte disturbances [240]. Chitin and its derivative, chitosan, are biocompatible, biodegradable, non-toxic, antimicrobial and hydrating agents; they provide good biocompatibility and positive effects on wound healing. Previous studies have shown that chitin-based dressings can accelerate repair of different tissues, facilitate contraction of wounds and regulate secretion of the inflammatory mediators such as interleukin 8, prostaglandin E, interleukin 1 β and others [241]. Chitosan provides a non-protein matrix for 3D tissue growth and activates macrophages for tumouricidal activity. It stimulates cell proliferation and histoarchitectural tissue organisation. Chitosan is a haemostat, which helps in natural blood clotting and blocks nerve endings reducing pain. Chitosan will gradually depolymerise to release N-acetyl-β-D-glucosamine, which initiates fibroblast proliferation, helps in ordered collagen deposition and stimulates increased level of natural hyaluronic acid synthesis at the wound site. It helps in faster wound healing and scar prevention [242].
A bilayer scaffold prepared from collagen and carboxymethyl cellulose for skin tissue engineering applications
Published in Journal of Biomaterials Science, Polymer Edition, 2018
Cemile Kilic Bektas, Ilgin Kimiz, Aylin Sendemir, Vasif Hasirci, Nesrin Hasirci
Human interleukin-8 (IL-8) is an alpha subfamily member of the chemokines (C-X-C) promoting phagocytosis and angiogenesis expressed at the first stages of the inflammations by monocytes, macrophages, T-cells, neutrophils and fibroblasts [60]. Keratinocytes increase secretion of IL-8 during wound healing [61], while fibroblasts secrete 100–1000 times more IL-8 compared to keratinocytes [62]. Many studies pointed out that IL-8 is one of the most important regulators in the skin during wound healing, epithelial regeneration and angiogenesis [63,64]. The results of the present study showed that IL-8 expression of the cells on BLColl increased continuously and reached 1300 pg/mL on Day 7, while on BLCollCS scaffolds IL-8 expression showed a peak on day 4, followed by a decrease (Figure 7). Similar to bFGF expression, increased growth rate of keratinocytes and confluency on whole surface on Day 4 may cause a decrease in IL-8 expression in the following days of culture.
Evaluation of the carcinogenicity of carbon tetrachloride
Published in Journal of Toxicology and Environmental Health, Part B, 2023
Samuel M. Cohen, Christopher Bevan, Bhaskar Gollapudi, James E. Klaunig
Holden et al. (2000) examined gene expression in CCl4-treated cultured hepatoma cells using DNA microarrays. Holden et al. (2000) reported that 47 different genes were either upregulated or downregulated by more than 2-fold after CCl4 treatment. Of note was the upregulation of proinflammatory cytokine interleukin-8 (IL-8), which was elevated over 7-fold compared with control. IL-8 protein levels were also measured and treatment with CCl4 produced a time-dependent rise in IL-8 protein expression which followed the increase in IL-8 gene expression. The IL-8 gene expression correlated with decrease in cell viability as evidenced by LDH release.
Association among blood BPDE-DNA adduct, serum interleukin-8 (IL-8) and DNA strand breaks for children with pulmonary diseases
Published in International Journal of Environmental Health Research, 2021
Hongxuan Kuang, Yanyan Dai, Xiang Ding, Yonghong Li, Caihui Cha, Wenhui Jiang, Haibin Zhang, Wenji Zhou, Yingwei Zeng, Qihua Pang, Ruifang Fan
IL-8 is an important biomarker of respiratory inflammation. Concentration of IL-8 in serum was determined by sandwich ELISA using a Human Interleukin 8 ELISA Kit (Boster Biological Technology, Wuhan, China). Each sample was analyzed in triplicate and the mean value was used as the final concentration. The detection limit of IL-8 was 2 pg/mL. The inter-day precisions of this assay ranged from 5.86% to 16.7%. All results were expressed as picograms of IL-8 per milliliter of serum (pg/mL).