Exam 1: Immune/Inflammatory response Flashcards Preview

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Flashcards in Exam 1: Immune/Inflammatory response Deck (34):
1

What is the purpose of the immune system?

• Neutralize, eliminate, or destroy microorganisms that invade the body
• To recognize and eliminate aberrant cells (i.e. cancer)

2

Differentiate self vs non self—why is this important?

• Immune system cells only mount a response against cells determined to be “non-self”
o Cells different from a person’s own healthy cells
• Self-tolerance: the ability of cells to recognize self vs non-self

3

What are the main cells of the immune system?

• Leukocytes (WBCs)
o Neutrophils, Eosinophils, Basophils, Macrophages & Monocytes, Dendritic cells, NK cells, T cells, Cytokines, B cells, Complement

4

What factors influence the immune system?

• Nutritional status
• Environmental conditions
• Medications
• Presence of diseases
• Age

5

What are the three processes involved in immunity? Which are specific vs nonspecific

• Nonspecific
o Inflammation

• Specific
o Antibody-mediated (humoral) immunity
o Cell-mediated immunity

6

What are the components of the immune system

• Skin and mucous membranes
• Mononuclear phagocyte system
• Lymphoid system
o Spleen, thymus gland, and lymph nodes
• Bone marrow

7

Identify the cells of the immune system: lymphoid


B cells
• Major cells of antibody-mediated immunity
• Able to produce antibodies
• Require help from T helper cells to respond
T cells
• Major cells of cell-mediated immunity
• T-helper cells (CD4+)
• Interact with antigens
• Secrete cytokines that stimulate B-cell proliferation and antibody production
NK cells
• Innate immune cells
• Can kill tumor cells and virally infected cells without previous exposure

8

Identify the cells of the immune system: myeloid

RBCs
• Erythrocytes, deliver oxygen to the tissues, iron rich hemoglobin binds to oxygen
Monocyte
• Immature macrophages
• Circulate in the blood stream for about 3 days prior to entering tissue and becoming macrophage
• Macrophages
o Called different cells in different tissue
o Life span from months to years
o Functions
 Phagocytosis
 Repair of injured tissue
 Antigen processing (CD4+)
 Secretion of cytokines to help control the immune system
Granulocytes
• Neutrophils
o 60-80% total
o Stem cells – mature in bone marrow
o Mature: segmented neutrophils (segs)
o Immature: (bands)
o 1st responder to infection
o No energy reserve (6 hour life span)
o Only mature form (segs) capable of phagocytosis
o Produce potent chemical mediators that enable them to destroy microorganisms
• Eosinophils
o Allergic reactions and infection by intestinal parasites
o Release inflammatory chemicals in areas of inflammation
o Primary function to kill parasitic helminths (worms)
• Basophils
o Release vasoactive substances (heparin, histamine) during inflammation
o Also involved in wound healing

9

Why are neutrophils important?

1st responders to infection

10

What are macrophages and why are they important?

• Carry out phagocytosis to destroy foreign invaders

11

What is complement?

• 20 plasma proteins that interact in a cascade fashion to produce important mediators of inflammation and immunity
• Can be activated by microbial agents (alternative pathway) or by antigen-antibody complexes (classical pathway)

12

What is the process of inflammation?

LOOK AT PACKET

13

What are the clinical manifestations; local and systemic

• Systemic
o Fever
o Neutrophilia (increased WBC)
o Lethargy
o Malaise
o Increased acute phase proteins (CRP)
o Increased erythrocyte sedimentation rate (ESR or sed rate)
• Local
o Redness, swelling, heat, pain

14

What cells are important to the process?

• Neutrophils, eosinophils, NK cells, macrophages

15

Identify nonspecific vs specific components of the immune system

• Specific adaptive immunity
o Acquired through previous exposure to infectious and other foreign agents
o Destroy specific foreign agents based on their distinct antigenic properties
o Recognizing foreign invaders, destroying them, and retaining a memory of the encounter such that an even more effective defense (adaptive) will be achieved upon subsequent exposure
o B and T lymphocytes are mediators
o B cells “humoral” immunity because the antibodies they produce are found in body fluids
o T cells produce cell mediated because they recognize antigens
• Nonspecific innate immunity
o Cellular and biochemical defenses that are in place before an encounter with an infectious agent
o Provide rapid protection
o Able to distinguish between self and non-self but not specific agents
o Major components
 Epithelial cells: block entry and secrete antimicrobial enzymes
o Phagocytic neutrophils and macrophages
 Engulf and digest microbes
o Dendritic cells (DCs)
o NK cells
 Kill intracellular microbes and foreign agents
o Complement system
 Amplifies the inflammatory response

16

Where do B and T cells mature?

• B cells – bone marrow and lymph tissues
• T cells – thymus

17

What is the MHC?

• Cluster of genes on chromosome 6
• Also known as human leukocyte antigen (HLA) complex
• Proteins made by these genes are displayed on the surface of body cells and mark them as “self”

18

Describe the process of antibody mediated immunity listing the main cells involved

• Memory B cells
o Contain antigen receptors and function in manner similar to memory T
o When exposed to the same type of antigen, respond rapidly with antibodies
• Plasma cells
o Short-lived antibody producing factories
o Have receptors on their surfaces that can bind antigens
o Each B cell binds only one particular antigen
• Long lasting immunity possible

19

What happens during and antibody-antigen interaction?

• Antibodies are proteins that specifically bind a particular antigen
• Antibodies have several functions
o Precipitation
o Agglutination: form large insoluble complex
o Neutralization: toxins bound or inactivated before they can interact with cells
o Opsonization: foreign antigen is coated making it more recognizable to phagocytic cells (happens in the spleen)
o Complement activation

20

How is immunity achieved?

• B and T cell functions are interdependent
• T cells cannot respond to soluble antigens
• On first exposure, B cells are minimally activated by antigen unless they are stimulated by cytokines from T cells
• Immunity = state of resistance against infection from a particular pathogen
• Provided primarily by adequate levels of circulating antibodies

21

What are the 5 immunoglobulins and where are they found

• IgG
o Most common
o Complement, crosses placenta
• IgM
o Activates complement
o ABO incompatibility (blood typing)
• IgA
o Secretions (mucus, saliva, tears, breast milk)
• IgD
o Stimulates B cells to multiply and mature
• IgE
o Parasites and respiratory infections
o Hypersensitivity reactions

22

What is innate vs adaptive immunity?

• Innate (natural) – in place before encounter, not specific
• Adaptive (acquired) – through previous exposure, specific

23

What is Active vs passive immunity?

• Active
o Acquired through actually having the disease
o Antigen enters the body and antibodies are created against it
o Natural active
 Person has disease
 Most effective and longest lasting
o Artificial active
 Small amount of antigen introduced
 Vaccinations, may require boosters
• Passive
o Temporary type transferred (in utero, breast milk)
o Antibodies introduced into the body
o Natural passive
 Mother to fetus across placenta
o Artificial passive
 Antibodies injected
 When person is exposed to a serious disease and has no known actively acquired immunity
 Rabies, snake bite, tetanus

24

Define this alteration in immune function: autoimmunity

• Inappropriate immune response; lack of differentiation of self
• Body attacks own tissue
o Recognizes self-cells as foreign and mounts an immune response that injures self-tissue
• Polygenic and multifactorial

25

Define this alteration in immune function: hypersensitivity

• Exaggerated or inappropriate response to specific antigens; overresponsiveness

26

•Define this alteration in immune function: immunodeficiency

• Lack of a response by a component of the immune system
• Due to missing component, damaged component, or missing step in parts of the immune system

27

Define this alteration in immune function: malignancy of WBC's

• Cancer of WBCs (Leukemia, lymphoma, plasma cell myeloma)

28

Know the four types of hypersensitivities, patho and examples

LOOK AT PACKET

29

Primary immunodeficiencies patho
IGA disorder

• Most common
• Familial, resulting in no circulating or secretory levels of IgA
• May be acquired, caused by medications or various diseases
• Chronic infections of the sino-pulmonary tract, GI tract, and GU tract
• Treatment: treat infections w/ antibiotics

30

Primary immunodeficiencies patho: Bruton X-Linked

• Males, females are the carriers
• Immature B-cells unable to produce antibodies
• Decreased IgG, IgM, and IgA
• No apparent health problems until 4-5 months (protected by IgG from mother)
• Recurrent infections: ear infections, dermatitis, pharyngitis, bronchitis, pneumonia, etc
• Treatment: Antibiotics (chronic, low-dose), IV Ig (passive immunity w/ antibodies

31

Primary immunodeficiencies patho: DeGeorge's syndrome

• Lack of development of thymus gland’ aplastic (doesn’t work) or hypoplastic (reduced function)
• T cells can’t mature
• Congenital (random mutational event)
• Associated with other developmental disorders: heart defects, hypoparathyroidism  hypocalcemia (tetany)
• Severe recurrent infections: viral, fungal, protozoan, and bacterial
• B-cell levels may be normal, but may have abnormal antibody response due to decreased helper T cells
• Treatment: antibiotics/anti-infectives

32

Chronic Mucocutaneous Candidiasis

• Autosomal recessive causing selective T-cell response
o Normal T-cell response to non-fungal pathogens
o Cannot respond to Candida
• Normal antibody responses
• Accompanied by endocrine dysfunction, parathyroid and adrenal glands

33

SCID

• Severe Combined Immune Deficiency Syndrome
• Inherited X-linked
• No immune system: lack B and T cells
• Severe recurrent infections and/or neoplasms
• Cannot live outside sterile environment
• Treatment: bone marrow transplant or gene therapy

34

Define HIV, what is the patho, and define the cells primarily infected

• Human immunodeficiency virus
• AIDS = Acquired immunodeficiency syndrome
• Defective cell-mediated immunity, especially decrease of CD4 or helper T cells
• Caused by retrovirus
• Retroviruses infect human cell and reverse transcriptase (enzyme) forces human DNA to use viral RNA
• This new DNA is incorporated into the human cell’s DNA and is now template for viral replication
• HIV attaches to and infects helper T cells and macrophages
• At risk for opportunistic infections and tumor formation
• Found in all body fluids, transmitted through blood, semen, vaginal/cervical secretions, amniotic fluid, and breast milk
• Classification based on CD4 counts
o >500 ul
o 200-400 ul
o