Process Of Inflammation Slideshare
Contents
What are the processes of inflammation?
INTRODUCTION – Inflammation is the immune system’s response to harmful stimuli, such as pathogens, damaged cells, toxic compounds, or irradiation, and acts by removing injurious stimuli and initiating the healing process, Inflammation is therefore a defense mechanism that is vital to health,
Usually, during acute inflammatory responses, cellular and molecular events and interactions efficiently minimize impending injury or infection. This mitigation process contributes to restoration of tissue homeostasis and resolution of the acute inflammation. However, uncontrolled acute inflammation may become chronic, contributing to a variety of chronic inflammatory diseases,
At the tissue level, inflammation is characterized by redness, swelling, heat, pain, and loss of tissue function, which result from local immune, vascular and inflammatory cell responses to infection or injury, Important microcirculatory events that occur during the inflammatory process include vascular permeability changes, leukocyte recruitment and accumulation, and inflammatory mediator release,
Various pathogenic factors, such as infection, tissue injury, or cardiac infarction, can induce inflammation by causing tissue damage. The etiologies of inflammation can be infectious or non-infectious (Table 1 ). In response to tissue injury, the body initiates a chemical signaling cascade that stimulates responses aimed at healing affected tissues.
These signals activate leukocyte chemotaxis from the general circulation to sites of damage. These activated leukocytes produce cytokines that induce inflammatory responses,
Steps of the inflammatory response:- (1) Recognition of the injurious agent, (2) Recruitment of leukocytes, (3) Removal of the agent, (4) Regulation (control) of the response, and (5) Resolution (repair).
What is the process of inflammatory phase?
Inflammatory Phase – Inflammation is the second stage of wound healing and begins right after the injury when the injured blood vessels leak transudate (made of water, salt, and protein) causing localized swelling. Inflammation both controls bleeding and prevents infection.
The fluid engorgement allows healing and repair cells to move to the site of the wound. During the inflammatory phase, damaged cells, pathogens, and bacteria are removed from the wound area. These white blood cells, growth factors, nutrients and enzymes create the swelling, heat, pain and redness commonly seen during this stage of wound healing.
Inflammation is a natural part of the wound healing process and only problematic if prolonged or excessive.
What is the process of inflammation and repair?
Introduction – Wound healing is a complex process involving soluble mediators, blood cells, extracellular matrix, and parenchymal cells ( Singer and Clark, 1999 ; Bullers et al., 2012 ; Pesce et al., 2013 ). The process from inflammation to the wound healing is divided into three phases: (1) inflammation process, (2) tissue formation, and (3) tissue remodeling (Figure 1 ; Eming et al., 2007 ).
The inflammatory phase is marked by platelet accumulation, coagulation, and leukocyte migration. The tissue formation is characterized by re-epithelialization, angiogenesis, fibroplasia, and wound contraction. Finally, the remodeling phase takes place over a period of months, during which the dermis responds to injury with the production of collagen and matrix proteins and then returns to its pre-injury phenotype ( Kirsner and Eaglstein, 1993 ; Castillo-Briceno et al., 2011 ; Bainbridge, 2013 ).
The normal healing response begins the moment the tissue is injured. Peripheral blood components filtrated into the site of injury, the platelets contact with exposed collagen and other elements of the extracellular matrix through the process from inflammation to wound healing ( Diegelmann and Evans, 2004 ).
This contact triggers the platelets to release clotting factors as well as essential growth factors and cytokines such as platelet-derived growth factor (PDGF), such as stimulation of DNA synthesis and chemotaxis of fibroblasts moreover smooth muscle cells to induce the production of collagen, glycosaminoglycan, and collagenase by fibroblasts through the wound healing process ( Lynch et al., 1987 ; Price et al., 2004 ; Tettamanti et al., 2004 ).
Furthermore, PDGF appears to transduce its signal through wound macrophages and may trigger the activation of feedback loops and synthesis of endogenous wound PDGF and other growth factors, thereby enhancing the cascade of tissue repair processes required for a fully healed wound ( Pierce et al., 1991 ).
In a normal response to injury, platelet aggregation and degranulation of the earliest events in an inflammatory response trigger the release of numerous inflammatory mediators including transforming growth factor-β (TGF-β) from the granules ( Wahl et al., 1989 ; Tatler and Jenkins, 2012 ; Christmann et al., 2013 ).
TGF-β is implicated in pathogenic fibrotic conditions in kidney, liver, and lung disease, and in scarring of skin wounds as well ( Martin, 1997 ; Sgonc and Gruber, 2013 ). Accumulating evidence indicates that TGF-β affects integrin-mediated cell adhesion and migration by regulating the expression of integrins, their ligands and integrin-associated proteins ( Margadant and Sonnenberg, 2010 ). FIGURE 1. The process from inflammation to the wound healing is divided into three phases: (1) Inflammation process, (2) tissue formation, and (3) tissue remodeling. The important question, “what is the key linkage between the tissue formation and inflammation?”
What is inflammation pathophysiology?
Abstract – Inflammation results from activation of the immune system in response to a broad range of different stimuli. The immune system is a highly complex and evolutionary optimized defense system with cellular and humoral components. The course of an inflammatory response is influenced by the immune condition of the host, the virulence e.g.
- Of an infectious agent, and the fine tuning of the local tissue reaction, which may be influenced by individual genetic factors.
- Immunity is a compromise between insufficient (immunodeficiency) or exaggerated (autoimmunity) immune reactions.
- The dynamic balance between these two extremes is achieved through stringent T- and B-cell selection in the bone marrow and thymus on the one hand and through “checkpoint control” in peripheral lymphatic tissues.
Many tumors have ways to suppress local immune responses and to escape destruction through the immune system (one of the so-called “hallmarks of cancer”). In recent years, different approaches have successfully been able to reverse this local immunosuppression.
