Chapter 1 - Overview of the immune system

Question 1

What do you call the the immune response directed towards one’s own cells?

Answer 1

autoimmunity.

Question 2

What do you call the immune reactions to substances that are not invasive or pathologic?

Answer 2

allergic or hypersensitivity rections.

Question 3

What are the two main fixed organs for immune activity?

Answer 3

lymph nodes and spleen.

Question 4

Name 3 cell mediators that can release proteins to mediate inflammation in cells and the destruction of agents?

Answer 4

Interferons, Interleukin, and immunoglobulins.

Question 5

What are the two main branches in the immune system?

What is the 3rd branch?

Answer 5

Mains:

1. innate immune system- responds to immediate foreign material
2. adaptive immune system- exposure to agent and trigger protective response.
3. Natural Killer (NK) cells- act on their own to recognize damage cells (cancer). Can act in presence of viruses, and kill cells by enveloping them.

Question 6

when is the innate immune system activated?

what are its components?

Answer 6

at birth- first line of defence.

physical barriers, WBC, and complement system

Question 7

What are the physical barriers of the body?

Answer 7

1. epithelial layer of cells (skin)
2. mucous layers (resp/GI system- use of cilia)
3. acid (stomach)

Question 8

Name the white blood cells of the innate immune system that are seen in a CBC differential, and describe them.

Answer 8

1. Monocytes- blood circulators, migrate into tissue and mature into macrophages.
2. Granulocytes- most abundant WBC, circulate blood and concentrate at sites of infection signalled by macrophages.

Question 9

Granulocytes counted in a CBC differential include which kind of specialized white blood cells? Describe them.

Answer 9

1. neutrophils- most abundant. They clear intruders via phagocytosis. Neutrophils are associated with intense inflammation
2. eosinophils- fight parasitic infections by releasing cytotoxic granule. They also release histamines.
3. basophils- release cytotoxic granules towards parasites. They contain histamines. These mediators cause edema and itching which contribute to typical allergy sxs

Question 10

Describe the complement system,

Answer 10

Consist of proteins that are made in the liver that have the functional role of complementing the actions of the immune cells.
these proteins are triggered by foreign molecular structures and start a cascade of complement reactions that result in molecular products that assist the actions of other WBCs.

Question 11

What are cytokines?

Answer 11

Cytokines are a broad and loose category of small proteins (Interlukings (asthma), interferons (viral infections/hep), tumour necrosis (R.A)) that are important in cell singling. Cytokines are peptides, which are secreted by certain cells of the immune system and have an activating effect on other cells. They cannot cross the lipid bilayer of cells to enter the cytoplasm but instead attach to cell receptors.

> > target for new medication to regulate self-destructive immune activity

Question 12

When and how does adaptive immunity develop?

Answer 12

After birth. cells/molecules from mediators of the adaptive system and work in conjunction with the innate immune system to amplify the strength of the response to an infectious organism.
- produces memory cells.

Question 13

what immunity system is represented by immunization?

How? (give an example)

Answer 13

Adaptive

a vaccine is an inactive component that allow the system to create antibodies in preparation for possible future invasion.

Question 14

What cells are included in the adaptive immune system? (2)

Answer 14

1. B-Lymphocytes

2. Immunoglobins / antibodies-

Question 15

Where do B-lymphocytes come from and what do they do?

Answer 15

B-lymphocytes mature in bone marrow- then in the plasma as a person ages.
They produce a unique immunoglobulin protein called an antibody that directs against a single antigen.

Question 16

What is an antigen?

Answer 16

molecular structure, such as a bacterium, that causes antibody generation or production of a specific antibody.
they can have more than one site recognized by the immune system.

Question 17

What are the 5 classes of immunoglobulin (Ig)?

What is their order of activation following an infection

Answer 17

IgM- first
IgG- second
IgA
IgD
IgE

Question 18

What is the basic functions of antibodies?

Answer 18

attach to infectious microorganism via the target antigen on the microorganism’s cell surface.

Question 19

What are the two types of T-Lymphocytes?

Answer 19

1. Helper T-Cells

2. Cytotoxic T-cells

Question 20

What can Cytotoxic T-lymphocytes do? (2)

Answer 20

1. recognize foreign antigens within host cells, and eliminate the infected sells.
2. recognize altered cells that have become malignant.

Question 21

What do Helper T-cells do?

Answer 21

regulate lymphocytes, other T-cells, and other immune cells.
they produce cytokines that regulate interleukins, interferons and tumour necrosis factor.

They help activate both other T-cells and B-lymphocytes

Question 22

What are Human Leukocyte antigens (HLA)?

Answer 22

Class of surface proteins found in nearly all human cells. These are the components of MCHs.
These components are different from person to person, and need to be reviewed for transplantation between donners.

Question 23

What are the two major gene classes of MHC, and what are their subclasses of HLA molecules?

Answer 23

1. MCH class 1: HLA-A, HLA-B, and HLA-C are proteins present on the surface of all human nucleated cells and on platelets.
2. MCH class 2: HLA-D, HLA-DR and HLA-DQ are present on the surface of immune cells like lymphocytes and monocytes.

Question 24

Which Screening Assays help with monitoring someone’s immune activity (2)?

Answer 24

1. CBC and differential count [WBC/RBC/Platelets]
2. Serum immunoglobulin levels.
   * use these tests comparatively or alone to inquire about further investigations.

Question 25

What are the normal limits of the following WBCs in a CBC report?

a) WBC
b) Neutrophils
c) lymphocytes
d) monocytes
e) Eosinophils
f) basophils

Name the disorder likely associated with abN readings of each WBC above.

Answer 25

WBC > 3,500;

neutrophils: 50%, >1,500 granulocytes, ^^^ during infection

Lymphocytes: 40-45%, >1,500, drop during viral infection,

Monocytes: <1,000, <10%, ^ during infection

Eosinophils: fights parasites, regulates histamines, ^ asthma/allergic reaction

Basophils: rarely ^ , histamine releasing cells. ^ levels= bone-marrow disorder.

Question 26

What is Eosinophilia?

Answer 26

When eosinophil count >500 cells/mm.

Question 27

How do you measure/assess serum immunoglobin levels?

Answer 27

serum globulin measurement&raquo_space; Use SPEP to see peaks.
work-up looks at IgG, IgA, and IgM.

a) increased serum globulin = acute immune response, chronic hep, connective tissue disease, chronic inflammatory.
b) Low serum globulin: needs a immunoglobulin electrophoresis to be done to show deficiency in a single class of immunoglobulin, like IgG .

Question 28

What is an SPEP?

Answer 28

a immunoglobulin electrophoresis. There are two results:

1. polyclonal gammopahty - wide low peak- represents the diffuse activation of B cells and is usually related to inflammation or immune-related diseases
2. monoclonal gammopathy- which a narrow peak (spike) not caused by immune response but multiple myeloma (plasma cancer).

Question 29

How does immunotherapy work?

Answer 29

uses the immune system and focuses treatments to target specific pathogens or target cells.

Question 30

What is immunosuppression and what causes it?

Answer 30

the partial or complete suppression of the immune response of an individual. This can be caused by corticosteroids, immunosuppressive medications, and medical disorders.

Question 31

How does Cancer Immunotherapy work?

Answer 31

Treatment that uses Monoclonal antibodies that target specific receptors on cancer cells that can be produced in labs.

Question 32

What do you call the antigens that cause hypersensitivity reactions or allergic reactions?

Answer 32

Allergens,

IgE immunoglobulins, are specific to an allergen, attaches to the surface of basophils.

Question 33

How does immunotherapy work in the tx of allergies?

Answer 33

attempts to desensitize individuals by exposing them to small amounts of the identified allergen extracts.
The purpose is to induce controlled tolerance.