Immunity to Infection Flashcards
This type of immunity relies on chemical and physical barriers, interferon system, complement system, phagocytosis/opsonization, and NK cells
Innate immunity
This type of immunity relies on antibodies and cytotoxic T lymphocytes
Adaptive immunity
This is an important part of what gives the adaptive immune system the ability to respond with specificity when encountering a pathogen in the future
Immune memory
There are 4 organisms to which we can build immunity to
Viruses
Bacteria
Parasites
Fungi
The first response to pathogens is mounted by the
Innate immune system
What parts of the innate immune system are involved in the immune response to viruses?
Cytokines and NK cells
What cytokines are involved in the innate response to viral infection?
Type I IFN (⍺ and β)
Type 2 IFN (γ)
IL-12
What do cytokines do?
Chemical messengers that cause biological response
Communicate with and outside the immune system
Involved in acute and chronic responses
What do NK cell do during a viral infection?
They kill body cells that are infected with a virus
What MHC class does the NK cell interact with to determine if a cell is infected?
MHC class I
What parts of the adaptive immune system are involved in the response to a virus?
Antibody-mediated response
Cell-mediated response
What is the role of antibodies in dealing with viruses?
Neutralization of free viruses
Opsonization of infected cells for phagocytosis by NK cell, macrophages, and neutrophils (ADCC)
Cytotoxic T cells (CD8)
This virus infects B lymphocytes
Epstein-Barr virus
These viruses (3) infect T lymphocytes
HIV
Human T lymphotropic virus (HTLV)
Measles virus
These viruses (2) infect macrophages
HIV
Cytomegalovirus
This virus encodes IFN-⍺ and β receptor homologs
Vaccinia virus; part of the poxvirus family
What happens as a result of the vaccinia virus creating receptor homologs?
Binds IFN ⍺ and β, preventing it from binding to cell receptors
This virus has a protein that blocks transport of MHC to the cell surface
Adenovirus makes E3 protein preventing the cell from being able to express on MHC molecules
There are 4 innate immune responses to bacterial infection
Antimicrobial peptides
Complement-mediated lysis
Phagocytosis (PRRs and PAMPs interact)
Opsonization
These responses ultimately cause damage to the pathogen membrane —> pathogen death
There are 2 antibody-mediated responses to bacteria
Agglutination —> blocking and neutralization of toxins
Phagocytosis (Ab mediated)
Gram (-/+) bacteria are resistant to lysis by complement and are dealt with by ab neutralization , opsonization, and phagocytosis
Gram +
Gram (-/+) bacteria are susceptible to the complement system
Gram -
This bacteria is involved in TB and is handled by phagocytosis and cell-mediated response
Mycobacterium tuberculosis
Spirochetes are handles by 3 immune mechanisms
Complement system
Neutralizing antibody
Cell-mediated response
This disease is caused by the plasmodium parasite
Malaria
What innate immune responses are involved in responding to parasitic infection?
Complement-mediated lysis
Phagocytosis (PRRs and PAMPs interactions)
Opsonization
What adaptive immune responses are involved in responding to parasitic infection?
Ab mediated response
Agglutination and blocking
Phagocytosis (with ADCC)
IgE/mast cell/eosinophil response
This disease is caused by a fungi that is part of the normal flora of oral, skin, and intestine. Likely to be found in immunocompromised hosts (AIDS pts, organ recipients)
Candidiasis - caused by candida albicans
What innate immune responses are involved in responding to fungal infections?
Barriers (skin, normal flora)
Phagocytosis (neutrophils)
Complement system (lysis and opsonization)
Does the adaptive immune system play a role in responding to fungal infections?
Yes but it’s not well understood
What regions interact on the antibody and phagocyte to enable ADCC?
Fc region on the antibody (pole of the “Y”)
Fc receptor on the phagocyte
Can all e. coli cause illness?
No; depends on the strain
Commonly found in the gut, most strains are harmless to humans
How does plasmodium cause anemia?
Replication in RBCs —> hemolysis —> anemia
Elevation of what 3 blood markers suggest parasitic infection?
Mast cells
IgE
Eosinophils
