N. Weiser M.D.
Professor of Pediatrics and Microbiology
Department of Microbiology
Perelman School of Medicine
University of Pennsylvania
402A Johnson Pavilion
3610 Hamilton Walk
Philadelphia, PA 19104-6076
SUMMARY OF RESEARCH
The Weiser lab investigates the molecular basis of host-pathogen interaction
for bacteria that reside in and infect the human respiratory tract. Most studies
focus on the pathogenesis of Streptococcus pneumoniae because of its prominence
as a cause of acute respiratory tract infection. Other pathogens under investigation
in the laboratory include Haemophilus influenzae, Klebsiella pneumoniae and
Staphylococcus aureus. Many projects focus on colonization of the mucosal surface
of the upper airway, the initial step in the disease process. Both host and
bacterial factors affecting colonization are under investigation. In general
these studies utilize bacterial genetics to examine effects of specific microbial
genes together with mouse models of colonization that allow for the use of
On-going projects examine:
- How colonizing microbes stimulate and evade innate immune clearance
- How the cellular immune responses acts to clear pneumococcal colonization.
that facilitate interspecies competition within a host.
- Mechanisms of competition
between co-colonizing pneumococci.
- Pneumococcal interactions with neutrophils
and mechanisms to evade killing by professional phagocytes.
- The host-microbe
battle for acquisition of iron on the mucosal surface and its implications
- The potential of live attenuated vaccines that colonize
and induce protective immunity but are avirulent
- The role of phosphorycholine,
a surface constituent of many respiratory tract pathogens, in pathogenesis.
surface components that undergo phase variation in their expression as a
mechanism of adaptation.