BACKGROUND:    Most uropathogenic @entity526 (UPEC) strains harbor genes encoding adhesive type 1 fimbria (T1F). T1F is a key factor for successful establishment of @entity293 . However, UPEC strains typically do not express T1F in the bladder urine, and little is understood about its induction in vivo. METHODS:    A flow chamber @entity281 model was used to grow UPEC under conditions simulating distinct @entity281 niches in the bladder. Type 1 fimbriation on isolated UPEC was subsequently determined by @entity375 cell agglutination and immunofluorescence microscopy, and the results were correlated with the ability to adhere to and invade cultured @entity1 bladder cells. RESULTS:    Although inactive during planktonic growth in urine, T1F expression occurs when UPEC settles on and infects bladder epithelial cells or colonizes catheters. As a result, UPEC in these sessile populations enhances bladder cell adhesion and invasion potential. Only T1F-negative UPEC are subsequently released to the urine, thus limiting T1F expression to surface-associated UPEC alone. CONCLUSION:    Our results demonstrate that T1F expression is strictly regulated under physiological growth conditions with increased expression during surface growth adaptation and @entity281 of uroepithelial cells. This leads to separation of UPEC into low-expression planktonic populations and high-expression sessile populations.

Uropathogenic XXXX Express Type 1 Fimbriae Only in Surface Adherent Populations Under Physiological Growth Conditions.

@entity1 :: ('9606', 'Species') :: ['human'] @entity281 :: ('MESH:D007239', 'Disease') :: ['infection'] @entity375 :: ('4932', 'Species') :: ['yeast'] @entity293 :: ('MESH:D014552', 'Disease') :: ['urinary tract infection'] @entity526 :: ('562', 'Species') :: ['Escherichia coli']
@entity526 :: (562,Species) :: ['Escherichia coli']
