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Advancement in Gene Delivery
Published in Rishabha Malviya, Pramod Kumar Sharma, Sonali Sundram, Rajesh Kumar Dhanaraj, Balamurugan Balusamy, Bioinformatics Tools and Big Data Analytics for Patient Care, 2023
Shilpa Rawat, Akash Chauhan, Rishabha Malviya, Md. Aftab Alam, Swati Verma, Shivkanya Fuloria
The human immune system contains two types of pathways that recognize an antigen from a foreign gene. One of the initial pathways for antibody release by B cells, lymphocytes begin their lives in the bone marrow. This is related to the immunoglobulin activity of the B cell receptor–antigen interrelationship. Immunoglobulins are hydrophilic proteins that travel through the bloodstream to reach the target antigen. The second pathway responds to antibodies generated by T cells, which go to the thymus gland and result in the development of T-lymphocytes. T cells are classified into two categories. The first contains T helper cells, which have a higher affinity for T cells or phagocytes, and the second contains killer cells (cytotoxic T-lymphocytes), which act by identifying a little bit of the virus on the extracellular region of the infected cells, resulting in lysis of the discovered infectious cells. As a result, preclinical investigations rapidly reveal that the recipient’s immune technique plays a crucial role in gene expression following gene delivery.
Wrong Resemblance? Role of the Immune System in the Biocompatibility of Nanostructured Materials
Published in Dan Peer, Handbook of Harnessing Biomaterials in Nanomedicine, 2021
Antibodies belong to immunoglobulin (Ig) superfamily of proteins and are exclusively synthesized by B cells in the lymph nodes or by plasma cells, a more differentiated state of B cells, which is able to produce approximately 3200 secreted Ig molecules per cell per second [3]. The ability of B cells to bind antigens is regulated by the B cell receptor, which is a membrane-bound form of antibody. During the maturation of B cell, the gene encoding the B cell receptor is rearranged and mutated in a random fashion, which leads to expression of a receptor with a unique ligand, i.e., antigen, recognizing potential. It is estimated that the resulting repertoire of unique B cell receptors are in the order of 1011, which is further expanded during B cell division by a high frequency of mutations in the antigen-recognizing part of the receptor [1]. This explains the astonishing ability of the immune system to produce antibodies to nearly any antigen introduced in the body. Before secreted antibody to protein antigens is produced, B cell maturation is required, which involves another subset of human immune cells, the T cells. The T cell is an important, albeit not the only, source of soluble factors (“cytokines”) that regulate the function of B cells and other leukocytes.
The Human Immune System Seen from a Biomedical Engineering Viewpoint
Published in Robert B. Northrop, Endogenous and Exogenous Regulation and Control of Physiological Systems, 2020
The antigen-presenting B-cells have B-cell receptor (BCR) proteins bound on their outer surfaces. The BCRs are surface-bound IgG antibodies; they, too, have enormous variability in their affinities for epitopes. When a certain BCR has a strong affinity to an epitope, it binds to that epitope, and then is internalized where the Ag protein is broken down, and pieces of it are bound to MHC II proteins, which are then externalized on the B-cell. If a Th has a TCR protein with affinity to the peptide epitope nestled in the B-cell’s MHC II protein, it binds to the antigen-presenting B-cell. A CD4 molecule on the Th must also bind to the side of the MHC II molecule to activate the Th, which secretes cytokines that cause the antigen-presenting B-cell to reproduce clonally with its BCRs that are specific for the Ag in question. This process is shown schematically in Figure 10.2. The clone of plasma cells grows identical BCRs with the affinity to the presented epitope. These BCRs are ultimately released as free antibodies. Since the original BCR bound to this epitope, the antibodies released are also specific for it and contribute to an amplified, humoral, immune defense.
The expression of microRNAs and exposure to environmental contaminants related to human health: a review
Published in International Journal of Environmental Health Research, 2022
Maria Rosaria Tumolo, Alessandra Panico, Antonella De Donno, Pierpaolo Mincarone, Carlo Giacomo Leo, Roberto Guarino, Francesco Bagordo, Francesca Serio, Adele Idolo, Tiziana Grassi, Saverio Sabina
In utero exposures to As can harm the developing fetus, increase the risk of spontaneous abortions, and lead to deleterious health outcomes (Farzan et al. 2013). Rager et al. conducted a study in which 40 cord blood samples were selected from mother-newborns pairs from a pregnancy cohort exposed to As. Microarray analysis revealed an increased expression of 12 miRNAs (miR-16-5p, miR-17-5p, miR-20a-5p, miR-20b-5p, miR-26b-5p, miR-96-5p, miR-98-5p, miR-107, miR-126-3p, miR-195-5p, miR-454-3p, let-7a-5p) associated with As exposure. Then, qRT-PCR was performed, considering only those miRNAs highly involved in disease-associated signalling network, namely miR-107 and miR-26b-5p. The analysis conducted on a subcohort of 10 subjects confirmed the microarray results. The 12 analyzed miRNAs, in line with bioinformatic analysis, were linked to immune response signalling pathways, such as triggering receptor expressed on myeloid cells 1 (TREM1), TLR, interferon signalling, protein kinase C theta (PRKCQ) signalling in T lymphocytes and B cell receptor signalling (Rager et al. 2014). Some of these miRNAs also have As-related health outcomes including cancer (let-7a-5p, miR-16-5p, and miR-20b-5p) (Lui et al. 2007; Cascio et al. 2010) and diabetes mellitus (miR-107, miR-126-3p) (Guay et al. 2011).
A complete immunoglobulin-based artificial immune system algorithm for two-stage assembly flowshop scheduling problem with part splitting and distinct due windows
Published in International Journal of Production Research, 2019
Three versions of Immunoglobulin-based Artificial Immune System (IAIS) algorithms are proposed by Chung and Liao (2013), Liu and Chung (2017) and Chung, Sun, and Liao (2017). The common point of the three algorithms is that they all focus on the effect or mechanism of B cells by the process before/after encounter with antigens. The differences between the three algorithms are as follows. The basic IAIS algorithm is first proposed by Chung and Liao (2013) for solving a hybrid flowshop problem. Liu and Chung (2017) based on Chung and Liao (2013) propose an immune-based algorithm for a two-stage supply chain scheduling problem by considering a special secondary immune response of memory B cells in addition. Chung, Sun, and Liao (2017) address a two-stage hybrid flowshop problem by IAIS algorithm with different encoding and decoding methods. It has been proved that the three IAIS algorithms are quite stable and efficient for hybrid flowshop, two-stage supply chain and two-stage hybrid flowshop problem. However, in the proposed problem with part splitting and distinct due window, the above IAIS-based algorithms may not be efficient. It is necessary to propose a revised algorithm with faster and deeper search ability. According to the book by Parham (2014), the lymphocytes, B cells and T cells, recognise by their receptors and destroy the pathogens that invade the human body in the natural adaptive immunity. While T cell is never considered in the above algorithms, the function of T cell is taken into account in this paper to build a strong IAIS algorithm. Each T cell with a receptor identifies the pathogens which have been captured by B-cell receptor and help B cell to destroy the pathogens. The proposed algorithm is named Complete Immunoglobulin-based Artificial Immune System (C-IAIS) algorithm.
Nonlinear dynamics of membrane skeleton in osteocyte
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2023
Zhuang Han, Lian-Wen Sun, Xin-Tong Wu, Xiao Yang, Yu-Bo Fan
The membrane skeleton exists in a wide variety of cells, and plays an important role in mechanotransduction and structural supporting, which mainly consists of spectrin and located under the cell phospholipid bilayer membrane (Bennett and Baines 2001; He et al. 2016). The membrane skeleton is first found in red blood cells and the elasticity of membrane skeleton can affect their shapes, adhesion, and signal transduction. The interactions between membrane skeleton and myosin IIA can control the red blood cell membrane curvature and deformability and blood rheology (Smith et al. 2018). The dynamic structure of membrane skeleton can change the function and membrane stability of red blood cells all along the cell’s circulatory life (Gokhin and Fowler 2016; Minetti et al. 2018). Then the membrane skeleton is found in nerve cells and it is a dynamically regulated platform for mechanical reception (Unsain et al. 2018; Zhou et al. 2019). The membrane skeleton influences axonal diameter and signal transduction by regulating the relative position and activation state of non-muscle myosin II and actin rings (Costa et al. 2020). The disassembly of the actin-spectrin-based membrane skeleton causes the actin destabilization and then induces the trophic deprivation of neuronal axon and leads to the axonal degeneration (Jia et al. 2020). What’s more, the rearrangement of the membrane skeleton caused by mechanical compression injury leads to the disruption of ionic equilibrium and eventually triggers the apoptosis and necrosis of dorsal root ganglion neurons (Quan et al. 2014). Besides these, the membrane skeleton also influences other cells. For example, the changes of membrane skeleton can affect the intraflagellar transport, which breaks the formation of microtubules and then prevents the cilium formation of Caenorhabditis elegans cells (Jia et al. 2019). The polymerization of membrane skeleton maintains the invaginated membrane system maturation in murine megakaryocytes (Patel-Hett et al. 2011), and controls the diffusion dynamics and signaling of B cell receptor through Igβ (Treanor et al. 2010).