Ⅴ-Immune Regulation, Host Defense Guards are Varied

Author : Rota

Update time : 2023-04-24 15:45:50

Immune Regulation, Host Defense Guards are Varied
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Multifunctional cationic host Defense Peptides and Their Clinical Application consists of 12 chapters. The selected sections of this article is Chapter 5 --Immune regulation, Host defense guards are varied

In fact, almost all cationic peptides can exert direct antimicrobial effects under appropriate in vitro conditions, especially when the peptide concentration is high or diluted in culture medium. However, in the host body, the direct antimicrobial activity of many cations-HDPs is inhibited due to their low concentration in the body or their antagonism with physiological concentrations of monovalent and divalent cations, serum and negative macromolecules (glucosamine glucosamine). Thus, several in vitro studies have demonstrated that peptides with direct antimicrobial activity do not exert fundamental resistance in the host. For example, the exogenous addition of human antimicrobial peptide LL-37 to mice is resistant to G+ bacteria infection, but in the presence of saline, even a high concentration - 100 μg/ml can not reduce the adhesion of bacteria in tissue culture medium . In contrast, at physiological concentrations, LL-37 can exhibit a series of additional biological functions, not directly targeting pathogens but selectively enhancing host defense mechanisms against microbial infections. The immunomodulatory activities of HDPs are diverse and include direct stimulation of chemotaxis and/or production of chemokines, inhibition of bacterial pro-inflammatory cytokine production, modulation of neutrophil and epithelial cell apoptosis, modulation of intracellular differentiation pathways, Regulates dendritic cell activation and differentiation and promotes angiogenesis and wound healing.

Selective enhancement of innate immunity through HDPs is a new anti-infection method that directly supplies bactericidal components. Although the bactericidal activity of HDPs is inhibited in the host, it can still exert its immunomodulatory effect. Potential concerns regarding direct cytotoxicity and hemolytic activity of HDPs in mammals can be minimized by reducing membrane hemolytic activity. The combination of anti-infective and anti-inflammatory activities of HDPs can reduce the risk of excessive inflammation, in contrast to the risk of tissue pro-inflammatory often seen with other immunomodulatory treatments. More importantly, since the basic target of immunomodulatory peptides is the host, it mainly affects pathogens by stimulating and increasing host immunity, so the selective pressure on pathogen resistance drugs is very small.

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Next : Ⅳ-Fighting Cancer Cells, Host Defense Guards Have Potential

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There are twelve chapters in Multifunctional Cationic Host Defense Peptides and Their Clinical Applications This article is serialized as an excerpt: Chapter 3 The Body's Defense Guards - Host Defense Proteins

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There are twelve chapters in Multifunctional Cationic Host Defense Peptides and Their Clinical Applications This article is serialized as an excerpt: Chapter 1 The Body's Defense Guards - Host Defense Proteins