Ch. 16 Innate Immunity

phagocytosis in the inflammatory response

A child falls and suffers a deep cut on her leg. The cut went through her skin and she is bleeding. Which of the following defense mechanisms will participate in eliminating contaminating microbes?

C3a and C5a

A microbe has the ability to inhibit complement activation of inflammation, but it cannot inhibit complement activation of opsonization and cytolysis. Therefore, the microbe has produced inhibitors of which complement protein(s)?

Antibodies

A response that is uniquely directed against pathogenic Bordetella pertussis would involve what component?

antibody synthesis.

All of the following are components of the inflammatory process EXCEPT -release of histamines and prostaglandins. -antibody synthesis. -chemotaxis. -dilation of blood vessels. -diapedesis

fever

All of the following are effects of histamine EXCEPT vasodilation. fever. redness. pain. swelling.

-production of antibodies.

All of the following are effects of kinins EXCEPT: -chemotaxis of phagocytic granulocytes. -production of antibodies. -drawing in neutrophils to infected or injure area. -vasodilation. -increased blood vessel permeability.

-they destroy infected body cells by phagocytosis.

All of the following are true regarding NK cells EXCEPT -they are found in tissues of the lymphatic system. -they are a type of lymphocyte. -they release toxic substances that cause cell lysis or apoptosis. -they destroy infected body cells by phagocytosis. -they have the ability to kill infected body cells and some tumor cells.

lysozymes

All of the following increase blood vessel permeability EXCEPT -histamine. -prostaglandins. -leukotrienes. -lysozymes. -kinins.

vasodilation

All of the following occur during inflammation. What is the first step? -margination -vasodilation -phagocyte migration -repair -diapedesis

- a jellyfish sting

An inflammatory response would result from which of the following? -a headache -a jellyfish sting -vomiting

Phagocytosis and the complement system

Antibodies directly interact with which innate defenses?

plasma cells

As mentioned previously, the second line of defense is activated when the first line of defense fails. In Part A, you identified one of these defenses as inflammation, which occurs when the body responds to a foreign antigen and increases fluid accumulation in a specific area. An added benefit of this excess fluid is that it also brings immune cells to the area to aid clearance of foreign antigens. In Julie's situation, that added fluid would bring immune cells to prevent any microbial infections that could be caused if microbes were introduced when she cut her finger. Which of the following cell types is NOT part of the second line of defense? -mast cells -basophils -plasma cells -eosinophils

1st: sebum, sweat 2nd: NK cells, fever 3rd: T lymphocytes, B lymphocytes

As you can see from this activity, the immune system is very complex and is made of many components. In this section, place each immune component in the appropriate bin (1st, 2nd, 3rd line of defense) NK cells T lymphocytes B lymphocytes sebum fever sweat

Helper T cells

B cells interact directly with __________.

the penetration and colonization by pathogens, and the diseases they cause.

Both the innate and adaptive defenses of the immune system work to prevent __________.

It is nonspecific and present at birth.

Describe innate immunity.

intact skin, tears, ciliary escalator

Describe some innate, physical defenses.

-involves binding factors F, B, and D to a pathogen

Describe the alternative pathway.

-involves phagocytes engulfing pathogens -involves secretion of waste products by phagocytes

Describe the lectin pathway.

-formation of phagolysosomes

Each of the following provides protection from phagocytic digestion EXCEPT: -M protein. -leukocidins. -biofilms. -formation of phagolysosomes

the migration of phagocytes through blood vessels to the site of tissue damage.

Emigration is __________.

They are physical barriers against invading pathogens

First line defenses have what aspect in common with each other?

Their capsules make them "slippery" to phagocytes.

How is Streptococcus pneumoniae able to avoid destruction by a phagocyte?

Protozoan phagocytosis is used for feeding; phagocytosis by immune cells is used to fight infection.

How is phagocytosis in the immune system different from protozoan phagocytosis?

a phagocyte

If a new bacterial pathogen entered a human body through an accidental needle stick, the first cell that would try to kill the pathogen would likely be __________.

The ankle is red, swollen, and warm to the touch.

If a person turns their ankle, how would one determine if damage to the tissue in the ankle has occurred?

1) Membrane attack complex will form. 2) Inflammation will be stimulated. 3) Pathogens will become opsonized.

In the Case of Classical Activation, Which Outcome Is Likely to Occur?

skin and mucous membranes

Inflammation is part of the second line of defense that is activated when the first line of defense is breached. Julie's first-line defenses were damaged when her injury occurred. Which of the following represents the first line of defense?

-production of antibody.

Innate immunity includes all of the following EXCEPT -production of antibody. -inflammation. -phagocytosis. -activation of complement. -production of interferon.

inflammation

Julie is preparing vegetables for dinner and accidentally cuts her finger. She washes it with soap and water before covering it with a bandage. A short while later, Julie notices that her finger is red, swollen, warm to the touch, and very painful. What describes the process going on in Julie's finger?

cell wall

Lysozyme and the antibiotic penicillin have similar mechanisms of action in that they both cause damage to the bacterial __________.

monocytes

Macrophages arise from which of the following?

adherence of phagocytes to the lining of blood vessels.

Margination refers to __________.

The innate immune system

Mucous membranes are a part of __________.

produce toxic oxygen products.

Neutrophils with defective lysosomes are unable to __________.

-they produce lysozyme

Normal microbiota provide protection from infection in each of the following ways EXCEPT -they compete with pathogens for nutrients. -they produce antibacterial chemicals. -they produce lysozyme. -they make the chemical environment unsuitable for nonresident bacteria. -they change the pH of the environment

1) C1 interacts with an antibody that is bound to a pathogen 2) C1 cleaves C2 and C4 3) C2a and C4b combine to form an enzyme 4) C3 is split into C3a and C3b

Once activated, the complement cascade is an ordered process. Each reaction leads to another reaction. This activity asks you to place the cascade reactions in the order they occur, starting with the C1.

-The swelling of the infected area destroys pathogens by squishing them.

One of the outcomes of complement activation is the stimulation of inflammation. Inflammation may result in redness, heat, swelling, and pain. Of the following, which is NOT a way that inflammation helps the body clear infection? -The redness is caused by more blood flowing to the infected area. -The swelling of the infected area destroys pathogens by squishing them. -Inflammation allows for more macrophages to come to the area of infection. -Inflammation causes diapedesis, which allows more neutrophils to the area of infection.

the ingestion of solid material by a eukaryotic cell.

Phagocytosis is defined as __________.

dead phagocytes.

Pus is comprised of __________.

AMPs

TLRs attach to all of the following EXCEPT flagellin. PAMPs. LPS. peptidoglycan. AMPs.

Memory cells allow subsequent immune responses against the same antigen to occur more strongly and more quickly.

The adaptive immune response, or third line of defense, is activated when the first and second lines of defense do not succeed in containing an infection. It is adaptive because the cells in this part of the immune system are capable of responding to specific pathogens. Another important feature of the third line is the ability of these cells to create memory cells. Why are memory cells an important product of an immune response?

an antibody

The classical pathway of complement activation begins with binding of __________.

chemotaxis

The process by which a phagocyte moves toward a chemical signal at the site of an infection is called __________.

opsonization C3b fragments bind to the surface of pathogens. Macrophages and neutrophils are attracted to C3 protein molecules bound to the pathogens, making them easier to phagocytize. inflammation stimulation C5a fragments recruit immune cells to the site of infection. Neutrophils are attracted to the area and arrive via diapedesis. C3a fragments act as chemotactic agents. direct cell lysis C9 is polymerized into a circular-shaped complex on the pathogen surface. Multiple transmembrane proteins are recruited to the pathogen. MAC introduces holes to the bacterial cell membrane.

There are three major outcomes of complement activation: opsonization, inflammation stimulation, and direct cell lysis. All three outcomes help the body destroy invading pathogens. In this activity, you will determine which statements are associated with opsonization, inflammation stimulation, or cell lysis. Drag each statement to the appropriate box, indicating whether the statement applies to opsonization, inflammation stimulation, or direct cell lysis.

-complement proteins found in perspiration

Unbroken skin poses a substantial barrier to microbes. All of the following contribute to this barrier except _____________. -the tightly-packed layer of dead, -keratinized cells -fatty acids within sebum -complement proteins found in perspiration -dryness of the skin

C5b

What activates the C6 complement protein?

pain, high heart rate, shivering, shortness of breath, sweaty skin, and disorientation.

What are common signs and symptoms of septic shock?

Antibodies, factor B, and mannose-binding lectin

What can activate the complement cascade in any of the three pathways?

They allow capillary walls to open and become leaky.

What direct effect do histamines and leukotrienes have on capillaries?

glycoproteins

What does the plasma membrane of a phagocyte attach to on a microorganism?

The structure that results from the fusion of a phagosome and a lysosome.

What is a phagolysosome?

To repair damaged tissue

What is the function of inflammation in response to a burn from a hot iron?

They create "handles" that make it easier for the pseudopods of phagocytes to attach to the microbe invader.

What is the role of opsonins?

The membrane attack complex (MAC)

What will a C6 deficiency prevent?

Cytotoxic T cells

Which cells directly attack abnormal cells in the body?

Coxiella burnetii

Which microorganism requires the low pH inside a phagolysosome in order to reproduce?

-mucociliary escalator - intestines

Which non-specific defense mechanism is mismatched with its associated body structure or body fluid? -very acidic pH - stomach -keratin and tightly packed cells - skin -mucociliary escalator - intestines -lysozyme - tears and saliva -cerumen and sebum - ear

antimicrobial peptides

Which of the following are best described as short chains of amino acids that are very stable and can have a variety of different antimicrobial activities, such as forming pores in bacterial plasma membranes and inhibiting cell wall synthesis?

Cells from damaged tissues and the complement pathway

Which of the following can release histamines? -Cells from damaged tissues -Invading bacterial cells -Cells from damaged tissues and the complement pathway -Wood from a splinter -The complement system

T lymphocytes

Which of the following defense systems would be involved in eliminating virally-infected cells?

-increased adherence of phagocytes to microorganisms

Which of the following is an effect of opsonization? -increased adherence of phagocytes to microorganisms -increased margination of phagocytes -increased diapedesis of phagocytes -inflammation -cytolysis

eosinophils

Which of the following is involved in resistance to parasitic helminths?

chemotaxis - chemical degradation inside a phagolysosome

Which of the following is mismatched? -pus - tissue debris and dead phagocytes in a white or yellow fluid -chemotaxis - chemical degradation inside a phagolysosome -diapedesis - movement of leukocytes between capillary walls cells out of blood and into tissue -scab - dried blood clot over injured tissue -abscess - a cavity created by tissue damage and filled with pus

-Streptococcus pyogenes

Which of the following microorganisms use M protein to avoid destruction of a phagocyte? -Haemophilus influenzae -Streptococcus pneumoniae -Coxiella burnetii -Streptococcus pyogenes

Exocytosis

Which of the following phagocytic processes occurs last in the sequence?

-Innate immunity is present at birth.

Which of the following statements about innate immunity is true? -Innate immunity is present at birth. -The innate immune response does not have a mechanism for detecting invading microorganisms. It is activated only in response to tissue damage or a signal from an infected cell. -Innate immunity involves specific recognition of microorganisms via a memory response. -It involves the activity of B and T cells.

It allows for an increased delivery of oxygen, nutrients, and phagocytes to the site of damage.

Why is vasodilation important to tissue repair?

A hole will form in the bacterium, allowing water to rush into the cell and causing lysis

You now know that once complement is activated, all outcomes occur. With respect to the membrane attack complex (MAC), which is most likely to occur once all of the C9 proteins insert into the bacterial plasma membrane?

-This pathway requires antigen-antibody complex -This pathway requires C1 to become activated -This pathway requires previous activation of the adaptive immune response

`Describe the classical pathway.