Blood Physiology: Immunity and Inflammation

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following is a characteristic of rhinitis?

Inflammation of the mucous membrane of the nose

Swelling of the mucous membrane of the nose

Runny nose

All of the above (correct)

What type of cell is heavily granulated and involved in inflammatory responses initiated by immunoglobulins IgE and IgG?

Lymphocytes

Monocytes

Mast cells (correct)

Basophils

Which of the following is NOT a common anaphylactic reaction?

Insect stings

Medications

Viral infections (correct)

Food allergies

What is the percentage range of monocytes in the total white blood cell count?

2-6% (D) Signup and view all the answers

Which of the following cells are responsible for humoral immunity?

B Cells (C) Signup and view all the answers

What is the primary function of tissue macrophages?

Destroy bacteria and other pathogens (D) Signup and view all the answers

Which of the following is NOT a type of tissue macrophage?

Neutrophils in the blood (A) Signup and view all the answers

Where are most lymphocytes located in the body?

Lymphoid organs (B) Signup and view all the answers

Which of these is NOT a systemic response to inflammation or injury?

Platelet aggregation (C) Signup and view all the answers

What is the primary function of fibroblasts during wound healing?

Producing collagen fibers (D) Signup and view all the answers

What is the role of thrombin in wound healing?

Promoting platelet aggregation (D) Signup and view all the answers

How do antibodies contribute to autoimmune diseases?

By attacking and destroying healthy cells and tissues (D) Signup and view all the answers

In type 1 diabetes mellitus, which cells are targeted by antibodies?

Pancreatic islet B cells (D) Signup and view all the answers

Which of these autoimmune diseases involves antibodies targeting acetylcholine receptors?

Myasthenia gravis (C) Signup and view all the answers

What is the general strategy behind therapeutic interventions for autoimmune disorders?

Replacing or restoring damaged function, reducing inflammation, and suppressing immunity (A) Signup and view all the answers

How does vaccination contribute to active immunity?

By stimulating the immune system to produce antibodies and memory cells (B) Signup and view all the answers

What is the primary function of B cells in the immune response?

Produce antibodies to neutralize pathogens (B) Signup and view all the answers

Which of the following can lead to leukocytosis?

Infection (A) Signup and view all the answers

What is considered a normal white blood cell count range?

4,000 - 11,000 per/mm3 (C) Signup and view all the answers

What is leukemia characterized by?

High numbers of abnormal blood cells (D) Signup and view all the answers

Which type of leukocytosis is considered the most common?

Neutrophilia (C) Signup and view all the answers

What is leukopenia associated with?

Reduction in white blood cell count (D) Signup and view all the answers

How do acute leukemias differ from chronic leukemias?

Acute leukemias have less differentiated cells (D) Signup and view all the answers

What can excessive exercise lead to in terms of leukocyte levels?

Neutrophilia (C) Signup and view all the answers

What is the primary function of neutrophils in the inflammatory response?

Engulf bacteria and debris (C) Signup and view all the answers

What process involves attracting neutrophils to an infection site?

Chemotaxis (A) Signup and view all the answers

Which immunoglobulin is primarily involved in the opsonization of bacteria?

IgG (D) Signup and view all the answers

What percentage of white blood cells do eosinophils typically account for?

1-4% (C) Signup and view all the answers

In which part of the body are eosinophils especially abundant?

Respiratory tract (A) Signup and view all the answers

What role do basophils play in allergic reactions?

Release of heparin and histamine (A) Signup and view all the answers

What is a common symptom associated with hives caused by allergic reactions?

Burning or stinging (B) Signup and view all the answers

Which condition is most closely associated with high levels of eosinophils?

Allergic diseases (C) Signup and view all the answers

What is one of the main functions of the lymphatic system?

Accessory return route to blood for surplus liquid (A) Signup and view all the answers

Which of the following is NOT a component of lymph?

Red blood cells (D) Signup and view all the answers

Which of the following is NOT an activity of immunity?

Transportation of oxygen (A) Signup and view all the answers

Which type of immune cells are derived from circulating monocytes?

Mast cells (B) Signup and view all the answers

What percentage of all leukocytes are neutrophils?

50-70% (A) Signup and view all the answers

What are the primary lymphoid organs responsible for?

Generating lymphocytes from progenitor cells (A) Signup and view all the answers

Which component is part of the immune system's physical barriers?

Skin (D) Signup and view all the answers

Which structure is involved in the production and maturation of lymphocytes?

Thymus gland (C) Signup and view all the answers

Which granulocyte is most abundant in the bloodstream?

Neutrophils (A) Signup and view all the answers

What is the purpose of the lymphatic system?

Drain excess interstitial fluid (C) Signup and view all the answers

How much blood plasma is reabsorbed into the blood vessels daily?

17 liters (B) Signup and view all the answers

Which of the following is a physical barrier in the immune system?

Skin (D) Signup and view all the answers

What is the average half-life of a neutrophil in circulation?

6 hours (C) Signup and view all the answers

Which organ is involved in making complement proteins?

Liver (B) Signup and view all the answers

Which of the following is an inappropriate immune response?

Autoimmune diseases (C) Signup and view all the answers

What fluid do lymphatic vessels carry?

Lymph (A) Signup and view all the answers

Study Notes

Blood Physiology: Immunity, Infection, and Inflammation

Immunity is the body's ability to resist or eliminate potentially harmful foreign materials or abnormal cells. These materials include viruses, toxins, carcinogens, fungi, pollution, bacteria, germs, and parasites.
Immunity involves various activities, including defense against invading pathogens (like viruses and bacteria), removal of worn-out cells and tissue debris, identifying and destroying abnormal or mutated cells, and rejection of foreign cells (like in organ transplants). Inappropriate responses like allergies and autoimmune diseases are also part of the immune system.
The immune system is a complex, functional system, not an organ system. Its components include the skin (a physical barrier), lining of mucus membranes, secretions (like tears and mucus – antimicrobial), blood cells and vasculature (WBCs), bone marrow, the liver (complement proteins), resident immune cells in most tissues, the lymphatic system, and lymphoid organs.

The Lymphatic System

The lymphatic system is part of the circulatory system and crucial for immunity. It's a network of lymphatic vessels, lymphoid organs, lymphoid tissues, and circulating lymph.
Lymphatic vessels carry clear fluid (lymph) directionally towards the heart.
Unlike the cardiovascular system, the lymphatic system isn't a closed system.

Lymphoid Organs

Primary lymphoid organs generate immature lymphocytes from progenitor cells and include the thymus and bone marrow.
Secondary lymphoid organs (like lymph nodes and the spleen) maintain mature lymphocytes and initiate adaptive immune responses. These organs are crucial for the production and maturation of some types of lymphocytes. Several lymph nodes, such as cervical, axillary, thoracic, etc. are part of the lymphatic system for bodily functions.

Relationship Between Cardiovascular and Lymphatic Systems

The heart pumps blood, roughly 5 liters per minute, with 7200 liters passing per day.
About 20 liters of plasma from blood pass into the interstitial space daily through capillary filtration.
Roughly 17 liters of filtered plasma are reabsorbed into the blood vessels; the remaining 3 liters stay in interstitial fluid.
The lymphatic system is a major drain of excess interstitial fluid that does not directly re-enter the blood vessels. This excess fluid is then filtered and drained via the lymphatic system.

Cellular Elements of Blood

Blood consists of plasma (55%), red blood cells (4%), white blood cells and platelets (<1%).
Key cell types include red blood cells, white blood cells, and platelets.

Phagocytosis

Phagocytosis is a cellular process.

Immune Effector Cells: Granulocytes and Agranulocytes

Granulocytes (polymorphonuclear leukocytes) include neutrophils, eosinophils, and basophils. These cells have cytoplasmic granules containing substances involved in inflammatory and allergic reactions.
Neutrophils are the most abundant white blood cells, with a lifespan of 6 hours and are crucial for inflammatory responses, particularly infections. They are phagocytes.
Eosinophils are involved with parasitic worms and allergic reactions; they are a less abundant type of white blood cell.
Basophils release histamine and heparin and are crucial in allergic reactions.
Agranulocytes include lymphocytes and monocytes.
Monocytes (macrophages) are involved with tissue-based immunity and releasing toxins including reactive oxygen species. They are part of the initial innate immune response.
Lymphocytes are key for adaptive immune responses, including B cells producing antibodies, and T cells directly destroying virus-invaded cells and cancer cells.

Examples of Cytokines

Interferons (IFNs) are secreted proteins that interfere with viral replication.
Interleukins (ILs) are signalling molecules affecting various aspects of the immune system and promote T and B lymphocyte development and differentiation.
Tumor necrosis factor (TNF) is a cytokine produced in response to tissue injury.

Complement Proteins

Complement proteins are plasma proteins that react with each other, essential for innate immunity, and enhancing adaptive immune responses.

Innate vs. Acquired Immunity

Innate immunity is the body's first line of defense, fast and non-specific, with no memory.
Acquired immunity is the body's second line of defense, slower, and specific, with memory.

Anatomical Barriers to Infection

Mechanical factors like skin, mucous membranes, and secretions (saliva, tears) help protect the body from foreign organisms.
Chemical factors like the acidic environment of the stomach, or antimicrobial peptides in sweat also help prevent infection.
Biological factors, like normal flora, compete with pathogens for nutrients and space.

Inflammation

Inflammation is a complex localized response to foreign agents (bacteria) or internally produced substances, initiating reactions including cytokines, neutrophils, adhesion molecules, complement proteins, and immunoglobulin G (IgG). It is often a key component of the body's innate immune response. Monocytes and lymphocytes are also involved later.
Increased capillary permeability, vasodilation, and swelling are associated with inflammation.
Inflammation has a key role in pathogen removal, limiting infection spread, stimulating an adaptive immune response, and initiating tissue repair.
Inflammation can be acute (short-term) or chronic (long-term). Chronic inflammation is often associated with tissue damage.

Wound Healing

When tissue is damaged, platelets bind to collagen and laminin.
Blood coagulation produces thrombin; it encourages platelet aggregation and the release of granules, initiating an inflammatory response.
Cytokines are released from white blood cells. Fibroblasts produce collagen fibers for scar-wound tissue formation.

Autoimmunity

In some situations, immune responses target self-antigens, leading to autoimmune disorders.
Examples include type 1 diabetes (pancreatic islet B cells), myasthenia gravis, and multiple sclerosis. Treatments focus on replacing damaged functions and reducing inflammation.

Vaccination (Active Immunity)

Active immunity develops when encountering a foreign organism; antibodies and T cells are activated, and the body develops immunological memory. Vaccines stimulate this process using dead or weakened microorganisms or toxins
Memory cells are crucial in forming this acquired immunity via vaccination

Passive Immunity

Temporary immunity occurs when antibodies or T-cells from another source (person, animal) are introduced to an individual.
This is often seen as antibody therapy

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers key concepts of blood physiology specifically focusing on immunity, infection, and inflammation. Explore how the immune system works to defend the body against pathogens and the mechanisms involved in response to foreign materials. Test your understanding of this vital aspect of human health.