Chapter 19: Flashcards
What is the difference between hypersensitivity and autoimmunity?
hypersensitivity - immune system is functioning and targeting normally but is giving an undesirable response (excessive)
autoimmunity - Immune system is functioning normally but is targeting abnormally (ends up attacking “self” cells and tissues)
Is the immune system functioning normally during hypersensitivity?
yes functioning and targeting normally but just excessive
Is the immune system functioning normally during autoimmunity?
no, self cells are mistakenly being attacked
what are the four types of hypersensitivity?
Type 1: anaphylactic hypersensitivity
Type 2: cytotoxic hypersensitivity
Type 3: Immune complex hypersensitivity
Type 4: delayed hypersensitivity
what are occurs in the body when hypersensitivity type 1 occurs? how? after how long?
localized anaphylaxis
caused by: asthma/ infection/ pollen/ slight food allergy
systemically anaphylaxis: anaphylactic shock
caused by: bee stings/ major food allergy
less than 30 minutes after exposure
what occurs within the body when hypersensitivity type 2 occurs? examples? after how long?
IgG and IgM cause membrane attack complex through complement
Rh Factor + thrombocytopenic purpura
5-8 hours after exposure
what occurs within the body when hypersensitivity type 3 occurs? examples? after how long?
antibody-antigen complex
serum sickness
2-8 hours after exposure
what occurs withing the body when hypersensitivity type 4 occurs? examples? after how long?
T cell response causing cell lysis
poison oak, poison ivy, cheap metals in jewelry
1-3 days
what are the four types of autoimmunity are there?
Type 1: cytotoxic reaction
Type 2: cytotoxic reaction
Type 3: immune complex autoimmunity
Type 4: cell-mediated autoimmunity
what occurs within the body when type 1 autoimmunity occurs? examples?
antibodies cause cell death
autoimmune hemolytic anemia
what occurs within the body when type 2 autoimmunity occurs? examples?
antibodies alter cell function
Graves’ disease
what occurs within the body when type 3 autoimmunity occurs? examples?
self antigens cause complex deposits
rheumatoid arthritis
what occurs within the body when type 4 autoimmunity occurs? examples?
CD8+ T cells react to “self” cells
type 1 diabetes, multiple sclerosis, psoriasis
What types of hypersensitivity requires B cell activity?
types 1-3
How does the body normally respond to an injected antigen during a type I hypersensitivity?
systemically anaphylaxis: anaphylactic shock
can be caused by: bee stings
What were some examples of type II hypersensitivity given in class?
Rh Factor + thrombocytopenic purpura
Which types of hypersensitivity can be linked specifically to IgG?
Type 2 and 3
Which type of hypersensitivity is dependent only on T cell activation?
Type 4
Which type of hypersensitivity has the shortest wait time for the onset of a reaction after exposure?
Type 1
How are TH17 CD 4+ T cells related to the autoimmunity?
Characterized by excessive inflammation within type 3 of autoimmunity (rheumatoid arthritis)
What are a few of the suspected causes of hypersensitivity and autoimmunity?
industrial pollutants
consequences of being too clean (hygiene hypothesis)
How does the hygiene hypothesis connect with H & A’s?
being too clean can cause lack of training of the immune system in order to fight off pathogens
Is the immune system functioning normally during immunodeficiency?
no, some or all of immune system is not functioning properly
What are the two most common causes of immunodeficiencies?
congenital - disorders are inherited
acquired - caused by cancer/virus
What does the abbreviation SCID stand for? how rare is this?
severe combined immunodeficiency
(1 in 100,000)
Is SCID a serious condition? How does SCID affect the immune system?
yes, it is the lack of adaptive immune system (no B or T cells)
What are the structural characteristics of HIV?
contains gp41 (aids in fusion)
contains gp120 (binds with CD4 T cell receptor CCR5 or CXCR4)
contains reverse transcriptase (allows for reproduction of virus and mutations)
Which type of HIV is common in North America, for the United States and Mexico?
HIV 1, group M: clade B
What allows HIV to change over the course of an infection?
reverse transcriptase creates mutations of new variants fairly often
What are the human host cell receptor and coreceptors that allow HIV to infect?
CD4 receptor
CCR5 or CXCR4 coreceptor
Which specific immune cell types are infected by HIV?
macrophages
dendritic cells
CD4+ T cells
How is the life cycle of HIV distinct from other viral families? Technically, this is review from lecture exam #2.
reverse transcriptase allows for virus to enter cell and remain latent or replicate its DNA
Which body organ becomes infested with large amounts of HIV?
lymph nodes
How is HIV most likely to be transmitted?
blood transmission would be most likely
sexual transmission would be second likely
You should know the names and descriptions of each phase of HIV infection.
Phase 1: asymptomatic phase: generally no significant symptoms besides occasional flu-like symptoms caused by ARS
Phase 2: Symptomatic phase: opportunistic pathogens cause infections (early indication of immune system failure)
Phase 3: AIDS: zero adaptive immune system
How does T cell number relate to disease progression? (You should know specific values). What is the normal value, before disease starts to affect the body?
T cell count goes down as disease progresses
Normal value: 800-1200
Phase 1: 1000-800 CD4 T cell/microliter of blood
Phase 2: 800-200 CD4 T cell/microliter of blood
Phase 3: 200 or less CD4 T cell/microliter of blood
What does the abbreviation ARS stand for? During which phase of HIV infection would ARS occur?
Acute Retroviral Syndrome: flu-like symptoms
during phase 1
What is a noticeable indicator that HIV infection has progressed to phase 2?
more frequent to secondary infections caused by opportunistic pathogens
What does the abbreviation HAART stand for? Why is treatment with HAART a challenge in developing countries?
Highly active antiretroviral therapy
-it is costly at 1,000 - 3,000$ per month
Which state has the most new HIV infections?
Florida
Which state contains the greatest number of people living with HIV infections?
New York
In the US, who is most at risk for becoming infected with HIV?
African-American homosexual males
Globally, who is most at risk for becoming infected with HIV?
women
explain the difference between a person that is HIV positive and a person who has AIDS.
HIV + = disease is latent but infection is present
AIDS = disease is active/ no adaptive immune system
true/false: in a vaccine preparation, the term attenuated means that the agent does not replicate?
false
true/false: immunological immunity is important for killing a recurring pathogen
true
what is the name of the sterol that is targeted in the cell wall of fungi
ergosterol
which of these is most known for being a topical antibiotic?
polymyxin b
protein synthesis inhibitors are stopping what process?
translation
