Cell-adhesion molecules, their role in leukocyte extravasation during acute inflammation

Leukocyte extravasation is the process of movement of leukocytes out of the blood vessels into tissue spaces. Normally leukocytes circulate in blood vessels and come out of the vessels randomly into tissue spaces, scanning the tissues for foreign substances before returning to blood vessels. From the tissue spaces, leukocytes drain into lymph and travel in […]

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Inflammatory mediators II

Plasma-derived inflammatory mediators Plasma contains two important interconnected systems that produce inflammatory mediators. The systems are: Kinin system Complement system Upon tissue damage which could result from infection, these systems Most components of these systems circulate in plasma in functionally inactive form, upon tissue damage, which could result from infection; these components of these systems […]

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Histamine, prostaglandins, and leukotrienes in acute inflammation

One significant thing about inflammation is that whatever the trigger may be, the tissue changes that occur during inflammation are the same. In other words, inflammation may occur resulting from injury, trauma, infection, burns or radiation, but irrespective of what might trigger an acute inflammation, the ongoing local tissue inflammation follows a certain pattern. The […]

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Inflammation – causes, events, significance, and consequences

Acute inflammation Inflammation is a complex series of events that occurs in vascularized living tissues in response to local injury or tissue damage. Inflammation is a programmed local tissue response that is peculiar to vascularized living tissues.In other words, inflammation is the response of vascularized tissues to local disturbances. The trigger for inflammation is tissue […]

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Antigen-presenting cells, a class of cells essential to the immune system

Antigen-presenting cells (APCs) Antigen-presenting cells are a class of immune cells that capture antigens, process the antigens and display fragments of the antigen for recognition by T-lymphocytes. Classical antigen-presenting cells are dendritic cells, macrophages, and B-cells. Aside from the classical antigen-presenting cells listed above, a good number of cells of the immune system (e.g. monocytes) […]

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Lymphoid organs play major roles in immune response

Lymphoid organs Lymphatic cells organize into lymphoid tissues and organs of various sizes and structural complexity. These tissues and organs broadly divide into two groups: primary lymphoid organs and secondary lymphoid organs. Lymph filters through many of these lymphoid organs and structures as it travels through lymphatic vessels. The lymphoid organs that play principal roles […]

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