ID immunology Flashcards
how do extracellular bacteria cause tissue destruction (2)
- induce inflammation
2. release toxins that kill host cells
major phagocytic cells (2)
- neutrophils
2. macrophages
what type of cells is the first to arrive at a site of infxn
neutrophil
what is the peptide sequence that phagocytes can recognize on bacteria?
RGD sequences (arginine, glycine, aspartic acid)
what organ is responsible for removing bacteria in the lymphatic system?
lymph nodes
what organ is responsible for removing bacteria in the blood system?
spleen
what can be released by neutrophils to rob microbes of iron?
lactoferrin
deficiencies in C5-9 results in?
neisseria meningitidis infxns
complement ___gram negative bacteria, and _____gram positive bacteria
lyses; opsonizes
what is the only class of Ab that can cross the placenta?
IgG
when is the neonate most susceptible to infxn
3-6 months after birth (mother’s IgG have disappeared)
what pathogens is the neonate most susceptible to (3)
- S. pneumoniae
- N meningitidis
- H influenzae type B
outcome of patients who are IgA deficient?
IgM can compensate
which Ab acts thru the mucosal epithelium?
IgA
which pathogen evades immunity by variation of surface Ag?
neisseria
what is the type III secretion system?
syringe secreting proteases across macrophage membrane to inhibit signaling pathway
septic shock results after release of ____ and ____ from macrophages due to Gram neg (and some gr+)
TNF-alpha and IL-1
superAg bind to class____MHC and to certain ______chains on T cells
II; V-beta
what do superAg result in?
activation of T cells & macrophages w/ TNF-alpha
what induces cross reactive Ab during pharyngeal infxns of rheumatic fever?
streptococcal M protein
in rheumatic fever, ____proteins are bound in heart
sarcolemma
T. pallidum ellicits what type of immunity?
CMI, humoral immunity
spirochetes (2)
T. pallidum, borrelia burgdorferi
what is most effective in clearing T pallidum infxn?
Th1 immunity
