Immunity to Bacteria Flashcards
Adaptive Immunity attacks bacteria by
- Neutralization by antibodies
- Complement activation
- opsonization
- macrophage killing
- Tc and Nk cells killing
Opsonization invovles
anitbodies and complement to increase phagocytosis
Bacterial toxins are
neutralized by antibodies and ingested by macrophages
bacteria in extracellular space are
opsonized by antibodies and complement, ingested and lysed
Bacteria in plasma are
activate complement, ingested and lysed
Brucella abortus method of intracellular survival
resistant cell wall and prevents phagosome maturation
Corynebacterium pseudotuberculosis method of survival
resistant cell wall
Listeria monocytogenes method of survival
neutralizes respiratory burst and escapes into teh cytosol
Mycobacerium tuberculosis method of survival
lipid cell wall, prevents phagosome maturation, suppresses antigen presentation and detoxifies oxidants
Salmonella enterica method of survival
prevents phagosome maturation, modifies endosomeal trafficking, detoxififes oxidants, downregulates NOS2 and NOX
Rhodococcus equi
survives in phagosomes
Mechanisms by which intracellular bacteria can evade intracellular destruction include:
- prevent lysosome-phagosome fusion
- escape into cytoplasm
- resistance to lysosome enzymes
- inhibit M1 polarization
- inhibition of autophagy
Skin infections include
microsporum and candida
respiratory infections include
histoplasma capsulatum, blastomyces dermatiditis, coccidiodes immitis
Opportunitistic infections include
rhizopus, mucor, absidia and pneumocystis
What cells respond to surface infections
Nk cells to destory fungal infections
What complement pathway responds to fungal infections?
alternative complement activation pathway
collectins
bidn to viral glycoproteins and block virus interaction with host cells
Defensins from leukocytes combat viruses by:
interfering viral transcription in host cells
What PRR recognize viruses?
RIG-1 and TLRs
Which interferons of type 1 respond to virus infections
IFN-alpha, beta, theta, delta epsilon
How do type 1 interferons combat viruses?
inhibit viral growth
How do type 2 interferons combat viruses?
IFN-y, activates macrophages and CD8 T cells and increases MHC 2 expression
How do Type 3 interferons combat viruses?
IFN-delta, acts as an immunoregulator of the Th1 response
What interferons are produced by viral-infected cells a few hours after a viral infection?
IFNalpha and beta
What is an antiviral state?
When IFN alpha and beta of a viral infected cell bind to nearby cells
Complement responds to virus by
causing virolysis, activating alternative pathway
How do antibodies respond to viruses?
phagocytosis and blockage of viral adherence
How do NK cells respond to viruses?
apoptosis
How do T cells respond to viruses?
apoptosis
How do activated macrophages respond to viruses?
phagocytosis and apoptosis
How do viruses evade the immune response?
antigenic variation prevent apoptosis target cytokines destroy immune cells Modulate MHC class 1 expression Inhibit antigen presentation
antibodies respond to protozoan infections by
opsonizaiton, agglutination and immobilization
Macrophages secrete what to combat protozoa?
NO
The innate immunity responds to what found in helminth cuticles and arthropod parasites?
Chitin
What cells produce chitinases?
mast cells, macrophages and neutrophils
How does the adpative immunity responde to helminths?
increase IgE secretion and Eosinophils
Atopy
excessive amount of IgE
atopic
affected animals of T1 hypersensitivity
What factors effect if an animal has allergies?
genetics and environmental factors
Over production of IL-4 in T1 hypersensitivity causes
increased Th2 activation and B cell stimulation
FceR1 is present on what cells?
MAST CELLS, BASOPHILS,NEUTROPHILS and eosinophils, macrophages and dendritic cells
FCeR2 is present on what cells?
B cells, NK CELLS, macrophages, DC, eosinophils and PLATELETS
FceR characteristics:
high affinity and irreversible binding
