Immunopathology - Week 2 - Learning Objectives Flashcards
What is cell injury?
INJURY is a pathological process in the tissue as
a result of any stress upon it.
What are the factors that influence how cells respond to stressors?
- The type of injury
- The duration of injury
- The severity of injury
- The current status of the tissue
- The adaptability of the tissue
Explain the process of Necrosis (Type III cell death)
Necrosis is an uncontrolled, often pathological cell death triggered by external factors, characterized by cell swelling, membrane rupture, and release of cellular contents, leading to inflammation and tissue damage.
Explain the relationship between ischaemia,
hypoxaemia, hypoxia, anoxia, necrosis and infarction
ISCHAEMIA: This refers to inadequate blood flow to tissues.
This lack of tissue
oxygen causes HYPOXIA which is defined as a decrease in tissue oxygenation. Low / poor levels of oxygen in the blood is called HYPOXAEMIA.
ANOXIA is defined as the absence of tissue oxygenation and may be due to
either ischaemia or a number of other causes.
When tissues die as a result of ischaemia, they become necrotic. NECROSIS
occurring as a consequence of ischaemia is called INFARCTION.
Describe the process of Apoptosis.
Apoptosis is a physiological process of cell death,
programmed into cells developing at a certain stage in
their life cycle
* It is a highly organized process, responsible for the
decrease in size of organs when this is needed
* Surrounding, surviving parenchymal cells then
phagocytose the cell fragments, and degrade them
using the components as nutrients
* The cell is shrinkage. There are no inflammatory or
other degenerative changes.
Describe the process of Autophagy.
Autophagy is a recycling process that makes the most of a cell’s already-existing energy resources. The process ramps up when your body has to make the most of these resources because your cells aren’t getting them from an outside source. With autophagy, a cell essentially eats itself to survive, and maintain homeostasis.
Physiological roles:
* In the development, cell proliferation,
remodelling, cardiovascular homeostasis,
ageing and the inflammatory process.
Pathological roles:
* In the disease processes such as metabolic
disease, neurodegenerative disorders,
infective processes etc
What are some examples of substances which may be accumulated:
Water -> Oncosis
Fat -> Steatosis
Glycogen -> Glycogen storage disease
Carbohydrates and Lipids -> Lysosmal storage disease
Proteins -> neurofibrillary tangles of Alzheimer’s disease
What are the type of cells/tissues being injured.
Labile cells:
Have constant ability to divide.
Stable cells:
Have the ability to divide occasionally.
Permanent cells:
Have lost the ability to survive.
