Cardinal Signs of Inflammation
- Pain
- Heat
- Redness
- Swelling
- Loss of function

Duration and Complications of Inflammation
- Acute inflammation lasts a few days
- Chronic inflammation can last months or years
- Complications of inflammation include asthma, pneumonia, and autoimmune diseases

Causes of Inflammation
- Infection
- Physical injury
- Autoimmune disorders

Classification of Inflammation
- Acute inflammation is the initial response to harmful stimuli
- Chronic inflammation involves a shift in cell types and simultaneous tissue destruction and healing
- Inflammation can also be classified as Type 1 or Type 2 based on cytokines and helper T cells involved

Inflammation and Infection
- Inflammation is the body's immunovascular response to harmful stimuli
- Infection refers to microbial invasion and the body's inflammatory response
- Inflammation can also be caused by non-infectious factors such as atherosclerosis and autoimmune diseases

Acute Inflammation
- Acute inflammation is the first line of defense against injury.
- Inflammatory mediators are short-lived and quickly degraded in the tissue.
- Acute inflammation ceases once the stimulus is removed.
- The inflammatory response involves the migration of leukocytes, mainly neutrophils and macrophages, to the site of injury.
- Acellular biochemical cascade systems, such as the complement system and coagulation system, also contribute to the inflammatory response.

Chronic Inflammation
- Chronic inflammation lasts for months or years.
- Macrophages, lymphocytes, and plasma cells predominate in chronic inflammation.
- Chronic inflammation is associated with diseases like diabetes, cardiovascular disease, allergies, and COPD.
- Factors like obesity, smoking, stress, and insufficient diet can promote chronic inflammation.
- A 2014 study reported that 60% of Americans had at least one chronic inflammatory condition.

Cardinal Signs of Chronic Inflammation
- Common signs and symptoms of chronic inflammation include body pain, arthralgia, and myalgia.
- Chronic inflammation can cause chronic fatigue, insomnia, depression, anxiety, and mood disorders.
- Gastrointestinal complications like constipation, diarrhea, and acid reflux can occur.
- Weight gain or loss may be observed in chronic inflammation.
- Frequent infections can be a result of chronic inflammation.

Vascular Component of Acute Inflammation
- Acute inflammation involves vasodilation and increased permeability of blood vessels.
- Vasoactive amines like histamine and serotonin, as well as eicosanoids like prostaglandin E2 and leukotriene B4, contribute to vasodilation.
- Nitric oxide released by macrophages and endothelial cells also contributes to vasodilation.
- Increased permeability allows plasma fluid, containing important proteins, to move into the inflamed tissue.
- The collection of fluid in the tissue causes swelling (edema) and facilitates antimicrobial actions.

Plasma Cascade Systems
- The complement system promotes opsonization, chemotaxis, and agglutination.
- The kinin system generates proteins that sustain vasodilation and other physical inflammatory effects.
- The coagulation system forms a protective protein mesh over injury sites.
- The fibrinolysis system counterbalances clotting and generates inflammatory mediators.
- These plasma cascade systems play a crucial role in the inflammatory response.

Cellular Component
- Leukocytes reside in the blood and move into inflamed tissue via extravasation.
- Some leukocytes act as phagocytes, ingesting bacteria, viruses, and cellular debris.
- Leukocytes release enzymatic granules that damage pathogenic invaders.
- Leukocytes release inflammatory mediators that develop and maintain the inflammatory response.
- Acute inflammation is mediated by granulocytes, while chronic inflammation is mediated by mononuclear cells.

Leukocyte Extravasation
- Neutrophils migrate from blood vessels to infected tissue via chemotaxis.
- Neutrophils remove pathogens through phagocytosis and degranulation.
- Inflammation is a protective immune response against foreign organisms.
- In autoimmune diseases, the immune system triggers an inflammatory response against normal tissues.
- Leukocyte extravasation involves leukocyte margination, endothelial adhesion, transmigration, and movement within the tissue via chemotaxis.

Phagocytosis
- Extravasated neutrophils come into contact with microbes at the inflamed tissue.
- Phagocytes express endocytic pattern recognition receptors (PRRs) that bind to non-specific microbe-associated molecular patterns (PAMPs).
- Actin-myosin cytoskeletal rearrangement occurs to endocytose the plasma membrane containing the PRR-PAMP complex and the microbe.
- Phagosome is trafficked to intracellular lysosomes, forming a phagolysosome that kills microbes.
- Opsonization enhances phagocytic efficacy by binding complement C3b and antibodies to microbial antigens.

Cell-Derived Mediators
- Lysosome granules in granulocytes contain enzymes that act as inflammatory mediators.
- GM-CSF, produced by macrophages, monocytes, T-cells, B-cells, and tissue-resident cells, contributes to inflammation in various conditions.
- Histamine, stored in mast cells and basophils, causes arteriole dilation, increased permeability, and organ-specific effects.
- IFN-γ, produced by T-cells and NK cells, has antiviral, immunoregulatory, and anti-tumor properties.
- Cell-derived mediators play important roles in inflammation and its associated effects.

Other Factors
- Inflammatory cytokines IL-1 and TNFα induce the expression of adhesion molecules on endothelial cells.