Patho Ex 2 Summer 26

Immune system function

Defense Against Pathogens

Remove Old/Damaged Cells

Cancer Surveillance

Maintain Homeostasis

Define antigen

Substance the immune system identifies as foreign

What type of antigens are most common

Proteins and glycoproteins

What are found in bacteria and blood type groups (antigens)

Polysaccharides/carbohydrates

What are natural boundaries we have against antigens?

Skin; mucous membrane; microbiome

What are the two types of immunity?

Innate and Adaptive

These are all types of …:

Present at birth

Rapid

General / nonspecific

Barriers: Skin, MM, microbiome

WBCs: Neutrophils, monocytes, macrophages, eosinophils, basophils, dendritic, NK

Innate immunity

These are all types of …:

Develop in response to exposure

Slower to develop

Specific

Antibodies

WBCs: T cells, B cells, plasma cells

Adaptive immunity

Innate is …; Adaptive is …

Passive; Active

Major immune system organs: … ; … ; …

Make; Train; Filter

Major immune system organs control the make, train and filter (global factors) while the minor component is more so …

Battleground sites (day-to-day)

What are the major immune system organs?

Bone marrow; Thymus; Lymph Nodes; Spleen

How does the bone marrow contribute to global immune system control?

Makes immune cells and matures B cells

How does the thymus contribute to global immune system control?

Trains and matures T cells

How does the lymph nodes contribute to global immune system control?

Filters lymph and activates immune responses

How does the spleen contribute to global immune system control?

Filters blood and fights blood-borne infections

Tonsils, a minor immune system organ, does what?

Monitor pathogens entering through the mouth and nose

Adenoids, a minor immune system organ, does what?

Help protect the upper respiratory tract

Peyer’s Patches, a minor immune system organ, does what?

Monitor pathogens in the small intestine

Appendix, a minor immune system organ, does what?

Supports gut immunity and beneficial bacteria

Mucosa Associated Lymphoid Tissue (MALT), a minor immune system organ, does what?

Protects mucosal surfaces throughout the body

Skin, a minor immune system organ, does what?

Provides a physical barrier against pathogens

Lymphatic Vessels, a minor immune system organ, does what?

Transport immune cells, antigens, and lymph

Mucous Membranes, a minor immune system organ, does what?

Trap and help remove pathogens from body surfaces

Dendritic cells, macrophages, and NK cells act as …

rapid responders to detect, engulf, and destroy pathogens

Dendritic has … with …

innate abilities; adaptive potential

The following cells are all …:

Neutrophils, monocytes, Macrophages, Dendritic, NK, Eosinophils, Basophils, Mast

Innate Immunity WBCs

Action of Neutrophil cells

Rapidly attacked bacteria/fungi; major cell in acute inflammation

First arriving to infection

Action of Monocyte cells

Circulate in blood; Become macrophages in tissues

Traveling clean-up crew

Action of Macrophage cells

Engulf pathogens, present antigens, release cytokines

Engulf invaders

Action of Dendritic cells

APC’s; Detect invades and alert system

Action of NK cells

Kill abnormal or infected cells without prior training

Destroy invaders

Action of Eosinophil cells

Fight parasites; Contribute to allergy/asthma inflammation

Parasite and allergy responders

Action of basophil cells

Release histamine and other mediators in allergic inflammation

Allergy alarm cells in blood

Action of Mast cells

Release histamine/cytokines in Type I hypersensitivity

Allergy alarm cells in tissue

B—lymphocytes, plasma and T—helper cells are types of …

Adaptive immunity WBCs

B—Lymphocyte action

Plasma cell progenitors; Support antibody production

Antibody-making factory builders

Plasma action

Produce antibodies/immunoglobulins

Antibody-making factories

T—Helper action

Coordinate immune response with cytokines; activate other cells

Immune commanders

Complement, Cytokines/interleukins/interferons, antibodies, histamine, prostaglandins/leukotrienes/TNF/IL-1, and proteases/collagenases are all …

Immune System Aids

Complement, immune system aid action

Helps antibodies remove or destroy targets

Cytokines / interleukins / interferons, immune system aid action

Coordinate, amplify, and recruit immune cells

Antibodies, immune system aid action

Recognize and target specific antigens

Histamine, immune system aid action

Drives immediate allergic-type reactions

Prostaglandins / leukotrienes / TNF / IL-1, immune system aid action

Promote inflammation, pain, and tissue effects

Proteases / collagenases, immune system aid action

Contribute to tissue destruction, especially in RA

Cytokines include … and …

Interleukins (IL’s) and Tumor Necrosis Factors (TNF’s)

Interferons (IFN’s) enhance … against viruses

First line defense

Yellow is …; Blue is …

Antibody; Antigen

What is an antibody?

Protein generated by plasma/B cells in response to antigen recognition

Custom adaptation to specific antigen

The … to a … is the basis of acquired immunity.

Generation of antibodies; foreign antigen

What are the 5 types of antibodies?

IgA; IgD; IgE; IgG; IgM

The IgA Antibody contributes to

Mucosal Protection

The IgD Antibody contributes to

B—cell receptor function

The IgE Antibody contributes to

Allergies and parasites

The IgG Antibody contributes to

Secondary “memory” response

The IgM Antibody contributes to

Primary “initial” response

The second rise in the IgG antibody is called …

Anamnestic response

The primary exposure is …; and during the first 10 days only … is being implemented

Infection or immunization; Innate immunity

Three goals of the antigen—antibody complex

Neutralize pathogens; Mark targets for destruction; promote removal from the body

What happens during neutralization?

Antibodies block viruses, bacteria or toxins from interacting with host cells

What happens during Opsonization?

Antibodies coat the antigen, making it easier for macrophages and neutrophils to recognize and phagocytose it.

What happens during complement activation?

IgG or IgM activates the classical complement pathway, leading to enhanced phagocytosis and sometimes direct lysis.

What happens during immune complex removal?

Antigen-antibody complexes bind complement proteins and are transported to the liver and spleen where macrophages remove them.

Erroneous … and … are the bases of autoimmune disease.

immune complex interactions; removal

Common joint autoimmune disorders

RA, Psoriatic arthritis, Ankylosing spondylitis

Common nervous system autoimmune disorders

MS, Myasthenia gravis

Common endocrine organs autoimmune disorders

Type 1 DM, Hashimoto, Graves

Common skin autoimmune disorders

Psoriasis, vitiligo

Common GI tract autoimmune disorders

Celiac disease, IBD

Common blood autoimmune disorders

Pernicious anemia, ITP

Common multiple organ autoimmune disorders

SLE

What is seen here?

Stinky; Strep throat

What is seen here?

Streptococcal pyogenes

What are the two common diseases which result from strep?

Rheumatic heart disease and Post—Strep glomerulonephritis

Example of Strep turning into Rheumatic heart disease? (image)

What is seen here?

Rheumatic heart disease

What is Post-Streptococcal Glomerulonephritis (PSGN)

Type III hypersensitivity reaction where immune complexes deposit in the kidneys' glomeruli following a strep infection, potentially leading to chronic kidney disease

What is Rheumatic Heart Disease (RHD)

Type II hypersensitivity reaction driven by molecular mimicry, where the immune system mistakenly attacks heart valves and tissue following strep pharyngitis

RA image example

Mutation Acquisition: … and … transform normal cells into tumor cells

Environmental; genetic carcinogens

Immunosurveillance: Ideally, the immune system … these cells and triggers …

identifies; DNA repair or apoptosis

Three E’s of progression?

Elimination; Equilibrium; Escape

Elimination; 3 Es

Immune system recognizes and kills tumor cells

Equilibrium; 3 Es

Poorly immunogenic tumor cell in dormant state

Escape; 3 Es

Tumor cells acquire new mutations that allow them to evade immunosurveillance, leading to malignant proliferation and clinical manifestation

Pathophysiological defect present in OA?

Defective remodeling of articular cartilage and subchondral bone

Primary underlying pathophysiology of RA?

Self—Directed autoimmune process

Initial drug of choice for OA?

Tylenol

Disease modifying anti—rheumatic drugs differ from others drugs in that DMARDs focus more on …

Treating the underlying disease process

For OA, trauma/loading increases …

cartilage/bone turnover

What do these describe:

Progressive articular cartilage deterioration

Subchondral bone thickening

Subchondral cysts

Osteophytes at joint margin

OA

What is seen here?

Hyper whitening; OA

What are the rules of common OA sites?

Large joints; weight bearing; asymmetrical

(can be found in small joints; hands/feet)

In terms of OA, inflammatory synovitis is … to joint damage and not …

secondary or byproduct; main driver

OA Tx goal

main control and maintaining activity

OA Tx; nonpharmacologic

Strengthen muscle, balance loading

Low impact, low load

Weight loss

Corrective bracing

OA Tx; pharmacologic

Tylenol (1st) — pot liver injury

Oral NSAIDs — pot kidney, GI, CV adverse effects

Topical NSAIDs — safer but less effective

How does Tylenol affect pain perception and increase hepati toxicity?

Tylenol is a central COX—3 inhibitor

— affects pain perception

— does not suppress inflammation

— less gastric irritation

— more hepatic toxicity

How do NSAIDs suppress inflammation and affect the body?

They suppress PGE2 via COX 1 inhibitor; a main source of inflammation

Increases usefulness in severe OA