I Can't Live Without You
The immune system includes these components
The most abundant WBCs, act as the first responders to injury or infection by engulfing & destroying bacteria
Neutrophils
Enlargement of the lymph nodes in the neck in conjunction with a sore throat
A key adaptive phase where activated T and B cells rapidly multiply to produce many effector cells for a specific immune response
Proliferation Stage
Programmed cell death without inflammation
Apoptosis (maintains homeostasis, aids development, and prevents cancer by destroying cells with mutated DNA)
What are the main purposes of the immune system?
Maintain homeostasis & phagocytosis (to destroy FBs and toxins)
A type of WBC, these engulf bacteria, foreign particles, and dying cells to protect the body. They bind to pathogens and internalize them, which acidifies and fuses with lysosomes to destroy the contents
Phagocytes
COVID-19, Measles, Influenza
Examples of disease processes, chronic conditions, and environmental exposures can activate, boost, or train the natural (innate) immune system to respond more effectively
Following recognition and proliferation, activated T and B lymphocytes perform specific cellular or humoral functions to eliminate pathogens
Response Stage
Large proteins that bind with specific antigens and serve to defend against foreign invaders
Antibodies
A single "hematopoietic stem cell" in the bone marrow gives rise to all different types of cells (lymphoblasts, immune system cells...further maturation occurs in organs and bone marrow (T cells and B cells)
These cells function to detect pathogens, toxins, and allergens, triggering immune responses through the release of mediators like histamine, protease, and cytokines
Mast cells
Antibodies received from another source, like mother's breast milk or rabies immunoglobulin (RIG)
Passive Immunity
Immune responses start when the body identifies foreign antigens. Lymphocytes and lymph nodes constantly survey the body, using microbial sensors to detect invaders and trigger their destruction.
Recognition Stage
Age-related changes in the immune system
A rapid, protective local response to injury, infection, or toxins that removes the cause, clears dead cells, and starts repair.
The Inflammatory Response
These cells are recruited to the site of inflammation after neutrophils
Monocytes, Lymphocytes, Mast cells
Develops due to prior exposure to an antigen via illness or immunization (vaccination); defends against disease upon re-exposure
Acquired (Adaptive) Immunity
An antibody-mediated, adaptive immune response occurring in bodily fluids (“humors”) that targets extracellular pathogens; B cells bind to antigens after receiving signals from helper T cells.
Effector Stage (or "Humoral")
Proteins produced by the cells of the immune system that determine the actions of the immune system cells
Antibodies
What are stem cells?
Special cells that migrate from bone marrow to the thymus gland that self-renew (divide via mitosis to create 2 identical cells or 1 new stem cell and 1 differentiated cell); found in almost all tissues of the body. No other cell in the body can do this.
These process antigens and present them to T cells, serving as a link between the innate and adaptive immune systems
Dendritic Cells
Present at birth, this first-line defense provides broad protection against infection. Examples include physical barriers (skin), chemical barriers (stomach acid, tears), white blood cells, and responses like inflammation and fever.
Natural (Innate) Immunity
Process by which T cells help tell B cells what a pathogen looks like, then B cells make antibodies to fight it. Some B cells also “remember” the germ, so if it returns, the body can fight it faster.
Antigen Recognition
Produced mostly by the liver, these proteins help the immune system by enhancing the ability to clear microbes and damaged cells
Complement (these "complement" the immune system)