micro exam 1 (from rosemary's quizlets)

What does an elevated WBC count mean?

infection

What does high C-reactive protein in the blood mean?

complement system is activated

Which is a rapid response: innate or adaptive?

innate

Which is a delayed response: innate or adaptive?

adaptive

True/False. The innate immune system has memory.

False

Is innate specific or non-specific?

non-specific

What is the cytokine-mediated fever mechanism?

1. Pathogen

2. Cytokines (IL-1, IL-6, TNF-alpha)

3. Hypothalamus

4. PGE2

5. Fever

What is the lymph node activation pathway?

1. Antigen-presenting cell

2. T-helper cell

3. B-cell activation

4. Dendritic cells migrate to nodes

5. T helper cells stimulate B cells -> antibody production

What does node swelling mean?

immune cell proliferation

What does IL-6 lead to?

fever and acute-phase proteins being activated

What is the link between innate and adaptive immunity?

It is sequential: innate -> adaptive

It is cooperative (they work together)

What makes mealses special with immunity?

It wipes out all the memory cells for every virus the pt has been exposed to before

What are the natural defense mechanisms of the oral cavity?

1. Oral mucosa

2. Nasopharynx-associated lymphoid tissues (tonsils)

3. Tongue

4. Saliva and salivary glands

5. Tooth plaque fluid and adjacent GCF

What are the two major mechanisms of innate immunity in the oral cavity?

1. Immune exclusion (inactivation, clearance of microbes from oral mucosa+enamel)

2. Inflammation (occurs when we need to remove infectious agent after mucosal penetration)

What is the difference between immune exclusion and inflammation?

- Immune exclusion is the inactivation and clearance of microbes from the oral mucosa/enamel BEFORE any mucosal penetration

-Inflammation is the next step that occurs when we need to remove the infectious agent AFTER mucosal penetration.

For the innate immunity in the oral cavity, what are ways that we use inflammation to remove the infectious agent?

1. Phagocytosis

2. Recognition of PAMPS by PRR

3. Inflammatory mediators

What do epithelial desolation, saliva flow, and mucin/agglutinins function for?

physical removal or microbes

What is the function of lysozyme?

causes cell lysis

What is lactoferrin's/ apolactoferrin function?

iron sequestration

What does the complement system function for?

activates neutrophils

What is secretory IgA's function?

prevents microbial adhesion and metabolism

What are IgG, IgA, and IgM's functions?

prevent microbial adhesion; opinions; complement activators

What parts of the oral mucosal epithelium help prevent penetration of microbes into deeper tissues?

- saliva

- keratin

- granular layer

- basement layer

What do cells in the oral mucosa express ______ for immune surveillance?

PRRs

What can some pathogens do to avoid being detected by the immune system?

- Some periodontal pathogens hide within buccal epithelial cells as a protective niche

What are some antigen-nonspecific denfense chemicals in oral secretions?

1. Calprotectin

2. Antimicrobial actions of saliva

3. Defensins

4. Gingival crevicular fluid

How can antigen-nonspecific defense chemicals in oral secretions help for an immune response?

- they can aggregate or agglutinate microbes

- they can promote or inhibit microbial adhesion

- they can directly kill or inhibit the growth of microbes

- they can contribute to microbial nutrition

How does calprotectin work?

- it is produced by nonkeratinized oral epithelial cells

- deprives microbes of essential divalent ions

- present in neutrophils, monocytes, macrophages

How does saliva act as an antigen-nonspecific defense?

- The flow of saliva and swallowing removes debris and unattached microbes

- It replenishes fluids in the oral cavity, which dilutes/clears microbes and acid from plaque

- Contains neurophils and antigen-nonspecific defense chemicals (secretory IgA, IgA, IgG) and other enzymes

How does defenses act as an antigen-nonspecific defense?

- it forms pores that cause osmotic instability and cell lysis

- It can be found in saliva

- it is active aganist fungi

- causes degranulation of mast cells

- chemotactic for neutrophils, dendritic cells, memory T cells

How does GCF act as an antigen-nonspecific defense?

- contains blood components including leukocytes are in the junctional epithelium

-

Normally, the flow of GCF is high or low?

low

What causes an increase of flow of GCF?

increases with inflammation to flush oral surfaces that are vulnerable to penetration by microbes

When does the composition of GCF change?

changes during inflammation increasing in the number of lymphocytes and neurophils

What is immune exclusion/colonization resistance?

bacteria that normally live in our oral cavity complete aganist pathogenic bacteria

What is an example of when a potential pathogens proliferate?

infection by the fungal pathogen Candida albicans after most of the commensal bacteria are killed by broad-spectrum antibiotics such as tetracycline

What is microbial antagonism?

one species harms, and can exclude, the other

What is synergism?

two species cooperate to benefit both

What is symbiosis?

one species benefit, other may be unaffected or harmed

What is commensalism?

one species benefit, the other is unaffected

What is mutualism?

both species benefit

What is parasitism?

one species benefits, the other is harmed

Where is MALT located and what is it responsible for?

MALT lies beneath the oral mucosal epithelium and contains phagocytes and APCs, which sample antigens in the oral mucosa and provide the link between innate and acquired immune response

What drives adaptive immunity?

MALT

What is found around the basement membrane to help eliminate pathogens that overcome innate immune exclusion and pass through the intact oral mucosal epithelium?

lymphoid cells

What are the extraoral lymph nodes and intraoral lymphoid tissues present in the mouth?

- palatine and lingual tonsils

- salivary gland lymphoid tissue

- gingival lymphoid tissue submucosal lympoid cells scattered in the submucosa

What and where does the lymph tissues drain from the oral cavity?

- network of lymph capillaries and lymph vessels links the oral mucosa, gingivae, and pulp to other structures, such as the tongue, and drain into the submandibular, retropharyngeal, and other lymph nodes

What are the two ways microbes can enter the lymphatic system?

1. Microbes have to overcome the innate immune system and penetrate through the oral mucosa

2. Transported to the lymphatics by phagocytes

When is an immune response elicited?

When the microbial antigens reach the lymphocytes in the MALT

What happens after the lymphocytes that have encountered an antigen is activated?

The lymphocytes leave the MALT via the efferent lymphatics and enter the circulation, after which they relocate to the lamina propria to drive the acquired immune response

What are the types of T cells in the lamina propria?

CD4 and CD8 but some intraepithelial lymphocytes (IELs

What is the most predominant T cells in the lamina propria?

CD4 and CD8 types

What are the B cells in the lamina propria associated with?

acini of the major and minor salivary glands and they synthesize IgA

What are some clinical connections to look out for in the oral cavity defense?

Reduced saliva -> xerostomia -> candidasis (easier for things to grow well in a dry environment

Neutrophil defects -> aggressive periodontitis

IgA deficiency -> recurrent infections

What is immunity?

state of protection against foreign pathogens or substances (antigens)

What is the first example of the first concept of immunity?

Thucydides 430 BC

What are some examples of when vaccinations worked?

smallpox

What is variolation?

take a pustle of someone who had the disease and scratched into the skin (early vacination)

What did Edward Jenner do for smallpox?

He used material from cowpox lesions to protect people against smallpox

What is attenuation?

When you use a weakened or aged culture that has lost its virulence to allow the body to mount a resistance but you do not get sick from it.

Who played with chickens and realized that if you used an attenuated culture then the subject didn't die?

Pasteur

When was the first human vaccination and on who?

1885 on Joseph Meister

Who made the rabies vaccination?

Pasteur

What is innate immunity?

"anatomic, physical barriers"

- mucous,

- tears,

- skin,

- cilia

- membranes

- chemicals (acid, enzymes)

- inflammation/fever

- phagocytosis

What immune cells are used in innate immunity?

Phagocytes and Natural Killer cells

What is aquired immunity?

"Physiologic and cellular barriers"

- T cells and B cells

- antibodies

- memory part of immune system

What are the defense chemicals in oral secretions?

1. Calprotectin

2. Defensins

3. Cathelicidins

4. Saliva

5. Lysozyme

6. Peroxidase

7. Histatins/Cistains

8. SLPI, PRP

9. Mucins

What is calprotectin?

starves microbes

What are defensins?

membrane pore forming peptide

What are Cathelicidins?

lysosomal antimicrobial polypeptide

What is in saliva that is used for the innate immune system?

Ig, lysozyme, lactoferrin, periodases

What is lysozyme?

aggregates microbes and amphipathic sequences

What is peroxidase?

oxidizes bacterial enzymes in glycolytic pathway

What are mucins?

aggregates bacteria, various effects

What is GCFs?

GCF: Gingival crevicular fluid

- Found in the sulcus under the gingiva (different than saliva) and is full of Igs, and other enzymes for protection

What immune cells use phagocytosis?

neutrophils, monocytes, and macrophages

What are pathogen associated molecular patterns (PAMPs)?

conserved patterns on the cells that the immune system can recognize as NOT our own (bacteria or pathogens)

What are some examples of PAMPs?

LPS, bacterial DNA, double-stranded RNA (viruses), glucans (cell wall of fungi) , flagellin

How do we recognize PAMPs?

with pattern recognition receptors (toll like receptors)

What are natural killer cells

nonphagocytic lymphocytes that kill virus infected cells, if it does not have MHC1 it kills the cell

What are the two receptors on a NK cell? How does it know when to kill a pathogen?

1. Antigen receptor

2. MHC I receptor

- If a cell does not express MHC1, the NK will kill the cell

What are acute phase proteins? What organ produces it?

serum proteins that are produced in the liver in response to tissue-damaging infections and other inflammatory stimuli

What is a C reactive protein?

acute phase protein that binds to bacteria to promote phagocytosis and activates the complement system

How does acute phase proteins work?

activates classical complement system resulting in increased clearance from a pathogen

What is the complement system?

has at least 30 components which interact in an ordered and tightly regulated manner to cause phagocytosis of target cells

What does opsonin do?

promote phagocytosis

What are the three important outcomes of activation?

1. Inflammation: anaphylatoxins promote the inflammation

2. Lysis: Membrane Attack complexes punches holes in membrane

3. Opsonin: enchange phagocytosis

What are the two lines of hematopoietic stem cells (HSC)?

myeloid line and lymphoid line

What are some characteristics of hematopoietic stem cells?

pluripotent and self-renewing

Cells from which HSC lineage are the first responders to infection?

myeloid

Cells from which HSC lineage lead to T and B cells?

lymphoid

What are the four main types of myeloid-erythroid progenitors?

granulocytes, macrophages, red blood cells, megakaryocytes (form platelets)

What are the the types of granulocytes?

neutrophils, eosinophils, basophils

What is the main circulating WBC, highly phagocytic, and usually first responder to infection?

Neutrophil

What is NETosis?

neutrophil exocytosis trap (traps microbes) that causes cell dealth without phagocytosis

What is the least abundant WBC that is a nonphagocytic cell involved with antiparasite defense and allergies?

basophil

What is similar to basophils but not found in blood only tissues, nonphagocytic?

mast cells

What cell is involved in parasitic infections and allergies, they have both phagocytic and extracellular killing?

eosinophil

What are some non granulocyte cells?

monocytes, macrophages, and dendritic cells

What do monocytes differentiate into?

Macrophages