Immunity Flashcards
(22 cards)
What’s autoimmunity?
When self tissue is perceived as foreign or dangerous
What are some examples of microbes?
bacteria, viruses, etc
What are Antigens?
large molecules (usually proteins or polysaccharides) that elicit specific responses from hosts
What’s an Epitope?
(antigen determinant): a specific discrete component of an antigen that attracts immune responses
What are the primary cells of adaptive immunity and what do they do?
- B- and T- lymphocytes (B- and T-cells)
- act as regulator cells, which assit in controlling and orchestrating the immune resopnse (e.g. by activating other cells) -also act as effector cell by killing/eliminating the microbe or antigen
There is always a large number of immune cells and other immune materials (like antibodies) circulating in the blood and lymph. This is known as ___ ___
humoral immunity
What’s an antigen?
any substance that causes an immune system to produce antibodies against it
What’s the aka for antibodies?
immunoglobulins
Which lymphocytes can become memory cells?
b-cells
Where do b- and t- cells mature?
b in bone marrow
t in thymus
What are the characteristics of IgG antibodies?
- 70 to 80% of antibodies are IgG
- the only Ig to cross the placenta (protects neonates)
- diffuses readily out of the vascular zone into the tissues
- antiviral, antitoxin, antibacterial actions
- activates killer cels
- activates the compliment system
What are the characteristics of IgA antibodies?
- predominant in saliva, tears, nasal and respiratory secretions
- also in breast milk (again, this will protect neonates)
- blocks entry of organisms to the eyes, gut, repiratory and urinary tracts
- protects mucosa
What are the characteristics of IgM antibodies?
- doesn’t leave the blood or lymph
- early responder
- first Ig formed after immunization
- activates complement system
- forms natural ABO blood antibodies
What are the characteristics of IgD antibodies?
- present in small amounts
- needed for B-cell maturation
What are the characteristics of IgE antibodies?
-tint amounts in plasma
-binds to mast cells (innate system) and liberates histamine and other inflammatory substances
-attracts eosinophils
-responds to parasites
IgE overreaction involved in allergic/hypersensitivity reactions, asthma, etc
-can be a genetic predisposition to produce excess IgE
What do antigen presenting cells do?
present antigens to T-cells and sometimes to phagocytes
Infections acquired in hospital are ___ while those acquired outside of healthcare settings are ___.
nosocomial infections; community acquired infections
Portal of Entry defined by: disruption in the integrity of the body’s surface barrier (kin or mucous membrane) as a site for invasion by infectious disease
penetration
Portal of Entry defined by: pathogens are transmitted directly from infected tissue or secretions to exposed, intact mucous membranes.
direct contact
Portal of Entry defined by: entry of infectious agent occurs through oral cavity and/or GI tract
ingestion
Portal of Entry defined by: entry of infectious agents through respiratory tract
inhalation
What is the term for bacteria that can live with and without oxygen?
facultative
