Intro to Immune System Flashcards

1
Q

What are the primary lymphoid organs and what cells do they produce?

A

Bone marrow – All cells except T-cells

Thymus – T-cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the secondary lymphoid organs?

A

Spleen
Lymph nodes
Mucosal immune tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What comprises the absolute white blood cell count?

A
Neutrophils
Basophils
Eosinophils
Monocytes
Lymphocytes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which leukocytes are mononuclear?

A

Monocyte
T-cell
B-cell
NK cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

These hematologic laboratory tests provide the complete hematologic picture of the case, and can often provide a diagnosis or diagnostic clues when interpreted by a physician.

A

CBC (complete blood count)

DIFF (differential leukocyte count)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What stain is used to observe and recognize leukocytes on a smear of peripheral blood?

A

Giemsa stain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

In a WBC (white blood count), what cells are present the least in the blood and which are the most?

A

Basophils

Neutrophils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Blood smear technique doesn’t allow differential count of B cells, T cells, and NK cells because these cells appear the same under a microscope. For this, a special technique called _______ _______ was developed using Abs recognizing specific Ags. These are selectively expressed one each type of leukocyte.

A

Cluster of differentiation (CD)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

CD molecules are cell surface markers useful for identification and characterization of leukocytes when cells can’t be differentiated based on microscopic morphology. CD Ags that are well characterized are assigned an arbitrary number (i.e., CD1, CD2). What are the CD Ag markers for the leukocytes?

A

T-Cell = CD3; CD4; CD8
B-Cell = CD19; CD20
NK Cell = CD56
Macrophage/Monocyte = CD14

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Direct (high level) and indirect (low level) ________ _______ with anti-CD Abs is used for identification of leukocytes in the specimen.

A

Fluorescent microscopy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the phagocytes?

A

Neutrophils
Macrophages

***Could also be granulocytes and DCs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The primary function of phagocytes is to ingest and destroy microbes and get rid of damaged tissues via their _______ function.

A

Scavenger

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How do phagocytes destroy microbes?

A

By ingesting them via phagocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Activated phagocytes also secrete ________ which promote and regulate immune responses.

A

Cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

If you have a lot of pus in a cut, what is largely present?

A

Neutrophils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Neutrophils mediate the earliest phases of _________ reactions.

A

Inflammatory

***Neutrophils produce inflammatory mediators – cytokines, prostaglandins, and leukotrienes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is present in the granules of neutrophils?

A

Peroxidase
Lysozyme
Degradative enzymes
Defensins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

T/F. Neutrophils are long-lasting and can function for months.

A

False. Neutrophils live for hours or a few days then die by apoptosis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

This is the term for an elevated WBC greater than 11,000 cells/mcL in non pregnant adults. It is a common sign of infection, particularly by extracellular bacteria.

A

Leukocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

This is the most common type of leukocytosis because these cells are the most abundant granulocyte in blood circulation.

A

Neutrophilia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The normal reaction of bone marrow to infection or inflammation leads to an increase in the number of WBCs, predominantly neutrophils and less mature cell forms. Termed the _________.

A

Left-Shift

***Means >5 percent immature neutrophils. The bone marrow is producing more WBCs and releasing them into blood before they are fully mature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

This is the term for the reduction in the circulating WBC count to less than 4000/mcL.

A

Leukopenia

23
Q

Leukopenia is usually characterized by _________, a reduced number of circulating neutrophils. Often caused by cancer chemotherapy or radiation therapy.

A

Neutropenia

***Suspect in people who have frequent or unusual infections.

24
Q

What are the ways a neutrophil can eliminate a pathogen intracellularly and extracellularly?

A

– Via phagocytosis and degradation by ROS or antibacterial proteins

– Antibacterial proteins are released from neutrophil into the ECM and kill

– Release of NETs (neutrophil extracellular traps) to ECM which immobilize pathogens and facilitate phagocytosis

25
Q

What are NETs composed of?

A

Core DNA element that attaches histones, proteins, and enzymes released from granules

26
Q

________ are the main “mononuclear” phagocytes in the blood, where as ________ reside in the tissues.

A

Monocytes

Macrophages

27
Q

________ lifespan can switch dramatically, from prolonged survival during inflammation to apoptosis as inflammation resolves.

A

Monocytes

28
Q

This is the term for an increased number of monocytes in the blood, and can occur in response to chronic infections, autoimmune disorders, certain cancers, and sarcoidosis (a proliferation of resident macrophages in tissues).

A

Monocytosis

29
Q

This is the term for a low number of monocytes in the blood. Can occur in people receiving chemotherapy.

A

Monocytopenia

30
Q

Tissue _______ _______ are a heterogenous population of immune cells that fulfill tissue-specific functions. They are long-lived cells derived from hematopoietic progenitors in the yolk sac.

A

Resident macrophages

***They are “residents” of specific tissues

31
Q

Monocytes migrate into tissues where they differentiate into ________ _______, especially during inflammation. They are involved in inflammatory reactions and tissue remodeling that repairs “collateral damage” produced by hypersensitivity reactions.

A

Inflammatory macrophages (monocyte-derived)

32
Q

These cells protect against helminthes (parasites) and are responsible for allergic reactions. They all have cytoplasmic granules filled with inflammatory and antimicrobial mediators.

A

Mast cells
Basophils
Eosinophils

33
Q

Mast cells are in the (BLOOD/TISSUE), while basophils are in the (BLOOD/TISSUE). Both contribute to defenses against parasites and play key roles in allergic and anaphylactic reactions.

A

Tissue

Blood

34
Q

Mast cells and basophils contain basophilic (purple-black) granules that contain…

A

Histamine
Serotonin
Heparin
Cytokines and chemokines

35
Q

These cells are the body’s “1st line of defense” because they distributed all over the tissues in locations where pathogens and allergens are frequently encountered.

A

Sentinel cells

***Mast cells; DCs; Tissue macrophages

36
Q

This is the term for a pathologic increase in mast cells within tissues.

A

Mastocytosis

37
Q

People affected by mastocytosis are susceptible to itching, hives, and anaphylactic shock, caused by the release of ________ from the abundant mast cells.

A

Histamine

38
Q

Most cases of mastocytosis are localized to skin and called cutaneous mastocytosis. ________ ________ is the most common form of cutaneous mastocytosis.

A

Urticaria pigmentosa

39
Q

The most prominent feature of the eosinophils are their large secondary granules containing four _______ _______.

A

Basic proteins (major basic protein)

40
Q

What is in the granules of eosinophils?

A

Histamine
Peroxidase
Lipase
Major basic protein

41
Q

T/F. Basic proteins of eosinophils are involved in anti-parasitic defense mechanisms as toxins directed against helminths.

A

True

42
Q

This is the term for a peripheral blood eosinophil count of >500/mcL.

A

Eosinophilia

43
Q

The most common cause of _________ in the US is allergic or atopic disorders (typically respiratory or dermatologic). Other causes are infections (typically parasitic) and certain tumors.

A

Eosinophilia

44
Q

These cells recognize and destroy a variety of target cells without any prior stimulation or immunization.

A

NK cells

45
Q

NK cells recognize Ags normally expressed on host cells. If one of those Ags is not expressed on host cells, the absence of that Ag activates NK cells. Because of this BROAD specificity for Ags, NK cell functions like a cell of _______ immunity.

A

Innate

46
Q

Where do B-cells mature?

A

Spleen

47
Q

When a (MATURE/IMMATURE) T-cell is Ag-stimulated, it gives rise to the development of cell-mediated adaptive immunity.

A

Mature

48
Q

Cell-mediated immunity mediates host defense against (EXTRACELLULAR/INTRACELLULAR) microbes, such as viruses and some bacteria, where they are inaccessible to circulating Abs. It is the killing of infected host cells that eliminates the reservoirs of infection.

A

Intracellular

49
Q

Some T lymphocytes, called _______ _______ also help B cells to make high affinity Abs and thereby contributing to the eradication of extracellular microbes.

A

T helper cells

50
Q

In cell-mediated immunity, T helper cells activate _________ to kill phagocytized microbes, or ________ ________ to directly destroy infected cells.

A

Macrophages

Cytotoxic T lymphocytes (CTLs)

51
Q

This is the term for the hypothesis that explains the specific nature of the immune response in which the diversity among various cells for the recognition of specific Ags exists prior to their exposure to the Ag. An exposure to a particular Ag causes the proliferation of the appropriate Ag-specific cell.

A

Clonal selection/expansion

52
Q

All immunocompetent individuals have many distinct lymphocytes, each of which is specific for a different ______.

A

Ag

53
Q

When Ag is introduced into an individual, lymphocytes with receptors for this Ag seek out and bind Ag and are triggered to proliferate and differentiate giving rise to _______ of cells specific for the Ag.

A

Clones

54
Q

The cells from the clones or their products specifically react with the Ag to neutralize or eliminate Ag. Some Ag-specific cells late in the immune response is responsible for the ________ involved in adaptive immunity.

A

Memory