CHALK TALKS Flashcards
What is BCG?
Live attenuated vaccine of M. bovis
How does BCG change the immune system>
induces epigenetic, transcripitonal, and functional reprogramming for TRAINED IMMUNITY
Effects of BCG vaccine on transgenic mice expressing human ACE2 with COVID infection
no change in mortality or viral load
how did they measure viral load of COVID (2)
TCID50 and plaque assay
effect of BCG vaccine on syrian golden hamster naturally expressing ACE2 with COVID infectio
no change in mortality or viral load but decrease body weight
roborovski hamster model
develops severe COVID phenotype
effect of BCG vaccine on roborovski hamster which COVID infection
no change in mortality or viral load but decrease body weight
how does COVID affect BCG trained immunity?
COVID causes vascular damage –> then virus disseminates to BM and prevents trained immunity by BCG
Is A. baumannii gram positive or negative?
gram negative
3 reasons why CRAB is antibiotic resistant
- complex OM
- LPS shields it from immune system
- efflux pumps
first candidate antibiotic for CRAB
protects mice from CRAB but causes mortality and moribund
4 benefits of second generation drug: ZAB
- decreased lipid plasma precipitation/increased lipophilicity
- decreased cholesterol, TAG, HDL
- increased solibility and stability
- decreased non-specific binding
what is the target of ZAB?
inhibits LPS transporter –> blocks LPS extraction from membrane and kills CRAB
why is there likely resistance to ZAB?
Only has 1 target
ZAB effect in vitro and in vivo
in vitro: decreased MIC
in vivo: dose-dependent decrease in bacterial burden
is S. pneumoniae gram pos or neg?
gram pos
current treatment for S. pneumoniae?
1 benefit, 2 downsides
POLYSACCHARIDE-based vaccines
benefit: effective for invasive S. pneumoniae
downside: only targets some serotypes and less effective in mucosal infection
what is IgA1?
most frequently produced Ab
2 forms of IgA1
Secreted (dimer)
Serum (monomer)
where is IgA1p found?
on S. pneumoniae via G5 domain
function of IgA1p?
requires Zn, cleaves proline-rich hinge on IgA1 heavy chain
N-terminal beta-helix shifts to accomodate IgA1 (open conformation)
drug against IgA1p?
mAb that holds IgA1p in closed conformation
2 purposes of IgA1p?
- prevent killing from phagocyte –> decouple Fc from Fab
- coat bacteria with non-functional Fab fragments to shield it from immune system