Immunology and Pathophysiology Quiz

Innate Immunity

• Types of immunity include innate resistance (natural barriers and inflammatory response) and adaptive (acquired) immunity.
• Lines of defense:
  • First line: Includes natural barriers like skin, low pH of skin, the linings of the gastrointestinal, genitourinary, and respiratory tracts, sloughing off of cells, coughing, sneezing, vomiting, urinating, mucus, and cilia.
  • Second line: Inflammation; characterized by rapid initiation, no memory cells, cardinal signs (redness, heat, swelling, pain, loss of function), and vascular responses (blood vessel dilation, increased permeability, and WBC adherence).
  • Third line: Adaptive (acquired) immunity.
• Biochemical barriers consist of antibacterial peptides present in mucus, perspiration, saliva, tears, and earwax.

Second Line of Defense: Inflammation

• Causes: Infection, mechanical damage, ischemia, nutrient deprivation, extreme temperatures, and radiation.
• Functions: Preventing and limiting infection, controlling inflammatory processes, and preparing the area for healing.
• Characteristics: Rapid initiation and no memory cells; characterized by cardinal signs of inflammation (redness, heat, swelling, pain, loss of function).
  • Vascular response: Blood vessel dilation and increased permeability, leading to WBC adherence and migration through vessels.
• Plasma Protein Systems in Inflammation: Complement system destroys pathogens (directly targets antibodies & antigens); clotting system forms a mesh to stop bleeding and prevent infection spread; kinin system.

Cellular Mediators in Inflammation

• Mast cells
• Granulocytes (neutrophils, eosinophils, basophils)
• Monocytes, macrophages
• Natural killer cells, lymphocytes
• Cellular fragments (platelets)
• Biochemical Mediators: Released from destroyed cells as well as from other cells to regulate inflammatory responses.

Cellular Receptors

• Pattern Recognition Receptors (PRRs): Recognize pathogen-associated molecular patterns (e.g., toll-like receptors, complement receptors, scavenger receptors).
• They initiate an inflammatory response in response to tissue injury.

Phagocytosis

• Key cells (e.g., neutrophils, macrophages) ingest and dispose foreign materials.

Manifestations of Inflammation

• Local signs: Heat, redness, swelling, pain, loss of function.
• Systemic signs: Fever, leukocytosis (increase in white blood cells), increased plasma protein synthesis.
• Exudate types: Serous (watery), fibrinous (thick, clotted), purulent (pus), hemorrhagic (contains blood). A type of exudate is a fluid that leaks from damaged cells.

Chronic Inflammation

• Lasts 2 weeks or longer
• Characterized by dense infiltration of macrophages and lymphocytes; granuloma formation.
• Causes: Unsuccessful acute inflammatory response, microorganisms, toxins, or irritants,

Wound Healing Stages

• Inflammation (cleanses the wound).
• Reconstruction (begins 3-4 days post-injury; lasts 2 weeks)
• Remodeling (scar formation over several weeks to years)
• Types Primary intention (minimal tissue loss) & Secondary intention (significant tissue replacement; scar formation).

Adaptive Immunity

• Characteristics: Recognizes foreign substances, provides long-term protection, and has memory.
• Key components involve T and B cells and antibodies (immunoglobulins).
  • Different classes of antibodies include IgG, IgA, IgM, and IgE.

Hypersensitivity Reactions

• Type I: IgE-mediated (e.g., allergies, anaphylaxis).
• Type II: Tissue-specific (e.g., Graves' disease).
• Type III: Immune complex-mediated (e.g., lupus).
• Type IV: T-cell-mediated (e.g., contact dermatitis).

Autoimmunity and Alloimmunity

• Autoimmunity: Immune system attacks self-antigens.
• Alloimmunity: Reaction against beneficial foreign tissues (e.g., transplants).

Immune Deficiencies

• Primary (congenital): Genetic defects in immune system components.
• Secondary (acquired): Caused by other diseases or conditions (e.g., HIV, malnutrition).

Chronic Inflammation

- Occurs when acute inflammation is unsuccessful.
- Characterized by dense infiltration of macrophages and lymphocytes leading to granuloma formation.

Test Review Questions

- What is often found in chronic inflammation?
- What are the functions of acute inflammation?
- What causes delayed wound healing?

Active vs. Passive Immunity

• Active (acquired): Body produces antibodies after exposure or vaccination; long-lasting.
• Passive (temporary): Antibodies from another source (e.g., mother's milk) are transferred; short-lasting.

Types of Antibodies and their roles

• IgE: Allergies and parasitic infections.
• IgM: First responder in infections.
• IgG: Provides long-term immunity; crosses placenta.
• IgA: Found in secretions (e.g., saliva, tears, breast milk).

Antigen Presentation

• APCs (e.g., dendritic cells, macrophages, B lymphocytes): Process and present antigens to T-helper cells to initiate immune responses.

Hypersensitivity Types and examples

• Type I: IgE-mediated (e.g., anaphylactic reactions)
• Type II: Tissue-specific (e.g., hemolytic anemia)
• Type III: Immune complex-mediated (e.g., lupus)
• Type IV: T-cell mediated (e.g., contact dermatitis)

Diseases and Clinical Signs of Imbalances

• Magnesium: Hypomagnesemia-neuromuscular irritability, tetany; Hypermagnesemia—muscle weakness, hypotension.
• Calcium -Hypocalcemia -muscle spasms; Hypercalcemia-decreased neuromuscular excitability, weakness, kidney stones, constipation.
• Potassium -Hypokalemia-decreased neuromuscular excitability, skeletal muscle weakness, cardiac dysrhythmias; Hyperkalemia-tingling, restlessness,intestinal cramping, weakness, paralysis
• Sodium-Hyponatremia free water excess; Hypernatremia-intracellular dehydration.

Renin-Angiotensin-Aldosterone System (RAAS).

• The RAAS is a hormone system that regulates blood pressure and fluid balance and sodium and water retention by activating a cascade of events. Blood pressure/sodium levels drop, activating the system. The kidney will release renin which converts angiotensinogen to angiotensin I and II, resulting in vasoconstriction, which will increase blood pressure. Angiotensin II will also stimulate the adrenal cortex to release aldosterone. Aldosterone causes the kidneys to retain sodium and water, further increasing blood pressure.

Acid-Base Imbalances

• Respiratory acidosis or alkalosis, & Metabolic acidosis or alkalosis.

Cancer Test Review

• Benign vs. malignant tumors. (Benign tumors are slow-growing, well-differentiated, and non-invasive; malignant tumors are fast-growing, poorly differentiated, and invasive).
• Carcinoma in situ (CIS).
• Genetic mechanisms of carcinogenesis (activation of proto-oncogenes, mutation of tumor suppressor genes, and mutations preventing apoptosis).
• Inflammation's role in cancer development.
• Active vs. passive immunotherapy.

Common Cancers in Children

• Characteristics and causes.
• Genetic factors, congenital factors, and environmental factors.

Types of Epigenetic Modifications

• DNA methylation, histone modification, and microRNAs. How they influence gene expression.

Test your knowledge on key concepts of immunology and pathophysiology with this quiz. Explore topics such as hypersensitivity reactions, inflammation, immunity, and electrolyte imbalances. Perfect for students studying health sciences or related fields.