cell injury and inflammation - group 4 sdca

Cell injury & inflammation Cell injury & inflammation

Cell Adaptation Cell Adaptation


CAUSES OF CELL INJURY:

•Hypoxia •Physical agents (heat, cold, radiation, trauma)•Chemical agents and drugs•Microbiologic agents •Immunologic reactions•Genetic defects•Nutritional imbalances



Normal Cell

[ homeostasis]

Normal Cell

[ homeostasis]

Adaptation Adaptation

Stress.increased demand

Cell injuryCell deathCell injuryCell death

Injurious stimulus

Inability to adapt



ATROPHY:

•Acquired shrinkage in the size of the cell.

HYPERTROPHY :

•An increase in the size of the cells and thus an increase in the size of the tissue or organ

•The end result is to lessen the amount of increased work that each individual cell must perform in response to the stimulation or stress



Cell injury & inflammation Cell injury & inflammation

HYPERPLASIA :•An increase in the number of cells in an organ or tissue

DYSPLASIA :• change in the appearance of cells after they have been subjected to chronic irritation.

METAPLASIA :•transformation of one adult cell type to another (reversible)

Body Defense Body Defense Body Defense Body Defense


IMMUNE SYSTEM

•Protects us against billions of bacteria, viruses and other parasites.

TWO CATEGORYa.Innate Immunity (Non-specific mechanism

Mechanical MechanismChemical MediatorsCellInflammatory Response


b. Adaptive Immunity (Specific Defense Mechanism)

Humoral Immune System (B cell)

Cell-mediated Immune System (T cell)


STAGES OF IMMUNE RESPONSE:

1.Recognition stage – antigen are recognize by circulating lymphocytes and macrophages.

2.Proliferation stage – stimulation of dormant’s lymphocytes.

3.Plasma cell = Anti-bodies = Cytotoxic cell = Release in blood stream

4.Effectors stage – Destroy by the Antibiotics.


INNATE IMMUNITY

It protects you against all antigens involves barriers that keep harmful materials from

entering your body the first line of defense in the immune response

a) MECHANICAL MECHANISM prevent the entry of microorganisms and

chemical into the body in two ways (1.) the skin and mucous membrane forms barrier that prevents their entry.

(2.) tears, saliva and urine act to wash them from the surfaces of the body.

b) CHEMICAL MEDIATORS – molecules responsible for many aspects of innate immunity

Interferons proteins that are produced when a cell is infected by a virus


Complement the operation is similar to that of clotting proteinsOnce activated certain complement proteins promote inflammation and phagocytosis and can directly lyse (rupture) bacterial cells.


c. CELL – white blood cells and the cells derived from white blood cells are the most important cellular components of immunity

Phagocytic Cellso Neutrophils – small phagocytic cells that are usually the first cells to enter infected tissue. o Macrophages – usually appear in the infected tissues after neutrophils & responsible for most of the phagocytic activity.


Cells of Inflammationo Basophils – could leave the blood and enter infected tissue.

o Mast Cells – nonmotile cells in connective tissue, especially near capillaries.

o Eosinophils – produce enzymes that break down chemicals released by basophils and mast cells.


Natural Killer Cells – recognizes classes of cells, such as tumor cells or virus-infected cells in general. Release chemical that damage cell membranes causing cell to lyse.

d. Inflammatory Response


ADAPTIVE IMMUNITY

only component of the immune system that confers any immunity against pathogens. It also enhances some effects of the innate immune system, such as inflammation and complement protein responses.


a. B cells produce antibodies. Antibodies attach to a

specific antigen and make it easier for the immune cells to destroy the antigen.

b. T cells attack antigens directly and help control of the

immune response. They also release chemicals, known as interleukins, which control the entire immune response.


Inflammatory Response


Inflammatory Response Inflammatory Response




“In-flame” – to set fire. (red, hot, pain)

Inflammation

“dynamic response of vascularised tissue to injury.”

It is physiologic, protective response.

Serves to bring defense & healing mechanisms to the site of injury.




CARDINAL SIGNS OF INFLAMMATION

Rubor (redness) • caused by hyperemia

Calor (heat)•caused by vasodilation

Tumor (swelling) •caused by fluid exudation

Dolor (pain) •caused by pressure of fluid exudates and chemical irritation of nerve endings

Loss of function •caused by swelling and pain




SYSTEMIC REACTIONS IN INFLAMMATION

1. fever2. increased WBC3. increased erythrocyte sedimentation

rate (ESR)




INFLAMMATION - MECHANISM

1. Vaso dilatation

2. Exudation - Edema

3. Emigration of cells

4. Chemotaxis

5. Phagocytosis




CLASSIFICATION OF INFLAMMATION

According to characteristic type of exudates:•Serous – clear; easily reabsorbed without damage•Fibrinous – filled with large amount of fibrinogen•Sanguinous or hemorrhagic – large amount of blood from vascular damage




•Purulent or suppurative – results from bacterial infection

•Catarrhal – mucinous secretion and results from viral infection of respiratory tract





According to position that inflamed area occupies within involved tissue:

•Abscess – localized collection of pus caused by suppuration in tissue, organ and confined space•Sinus – infection forming abscess develops suppurating channel and ruptures onto the surface or into a body cavity




•Fistula – infection forms a tube-like passage from an epithelium-lined organ or normal body cavity to the surface of another organ or cavity

•Cellulitis – inflammatory process poorly defined and diffused with tendency to spread; involves cellular or connective tissue

•Ulcer – superficial defect on surface of organ or tissue caused by sloughing of necrotic tissues





According to duration or length of time•Acute

Lasts less than 2 weeks; response is immediate; healing takes place with return of normal structure and function




•Chronic Lasts from several weeks to years; debilitating and produces long lasting effect; proliferative cell multiplication, cellular filtration, necrosis, fibrosis or scarring; with periods of

Remission – disease is present but the person does not experience symptoms

Exacerbation – acute phase, signs and symptoms are back

Altered Immune Response Altered Immune Response

Altered Immune Response





IMMUNE SYSTEM DISORDERS occur when the immune response is inappropriate, excessive, or lacking.

Complications related to altered immune responses include:

Allergy or hypersensitivityAnaphylaxis Autoimmune disorders




Blood transfusion reaction

Disease development

Graft versus host disease

Immunodeficiency disorders

Serum sickness

Transplant rejection

Thank You !!!

cell injury and inflammation - group 4 sdca

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