4)Inflammation Flashcards
Briefly describe the acute inflammatory response.
Acute inflammatory response is the immediate response to an injury or infection within the first minutes or hours. It involves both the vascular response (redness, swelling, pain and heat) and a cellular response (neutrophils and macrophages).
Describe the cellular component of the inflammatory response showing the role of neutrophils and monocytes.
Neutrophils migrate from the blood and carry out phagocytosis. Monocytes migrate from blood to tissue and mature into macrophages, which also carry out phagocytosis. Phagocytosis uses digestive enzymes from lysosomes and oxygen free radicles to engulf a cell.
What is the role of histamine in the inflammatory response?
Histamine triggers the relaxation of the smooth muscle cells, causing vasodilation (dilation of blood vessels). Histamine causes the concentration of endothelial cells, causing gaps to form between them. This increases vascular permeability to allow neutrophils and monocytes to squeeze through the gaps by diapedesis.
Describe the main stages of phagocytosis.
After attachment the phagocyte internalises the microbes into a phagosome, it then fuses with a lysosome to create a phagolysosome. Inside the phagosome there is a high concentration of free oxygen radicals and digestive enzymes that destroy the pathogen.
Describe, two vascular changes observed in response to inflammation and briefly explain the reason for each one. (4 marks)
1) Vasodilation- Occurs due the the relaxation of smooth muscle cells in the tunica media/ muscle layer caused by histamine or cytokines released from mast cells.
2) Increased permeability- Occurs due to concentration of endothelial cells lining the blood vessels caused by histamine or cytokines from mast cells.
Describe, two cellular changes observed in response to inflammation and briefly explain the reason for each one. (4 marks)
1) Neutrophils moves from blood into tissues then carry out phagocytosis.
2) Monocytes move from blood into tissues and differentiate into macrophages then carry out phagocytosis or release growth factors of cytokines IL-1 or TNF alpha.
What is involved in the chronic inflammatory response?
Any prolonged inflammation that does not heal on its own this can last for years. Mediated by macrophages and lymphocytes. More tissue destruction that acute inflammation. Damaged celled are replaced by fibroblasts causes by fibrosis and scarring. Entire area is often permeated by newly formed blood vessels due to vasodilation.
State the names of four types of white blood cells involved in the innate immune response. (4 marks)
Neutrophils, monocytes, macrophages & mast cells.
Define systemic inflammation and state three characteristic signs of this inflammatory state. (4 marks).
Systemic inflammation is inflammation throughout the whole body. Signs include: Fever, Sweating, Tachycardia which is high heart rate over 90 BPM, Tachypnoea which is high respiratory rate over 20 Breaths PM.
Explain the roles of pro-inflammatory cytokines in the inflammatory response (4 marks).
pro-inflammatory cytokines are released from macrophages. They are IL-1 & TNF- alpha. They promote inflammation by acting on the hypothalamus to cause fever, stimulate, chemotaxis from leukocytes and stimulate leukocytosis.
