Open AccessDo type 1 fimbriae promote inflammation in the human urinary tract?
Author(s) -
Bergsten Göran,
Wullt Björn,
Schembri Mark A.,
Leijonhufvud Irene,
Svanborg Catharina
Publication year - 2007
Publication title -
cellular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.542
H-Index - 138
eISSN - 1462-5822
pISSN - 1462-5814
DOI - 10.1111/j.1462-5822.2007.00912.x
Subject(s) - fimbria , urinary system , biology , inflammation , microbiology and biotechnology , tamm–horsfall protein , bacteriuria , escherichia coli , immune system , immunology , gene , endocrinology , genetics
Summary Type 1 fimbriae have been implicated as virulence factors in animal models of urinary tract infection (UTI), but the function in human disease remains unclear. This study used a human challenge model to examine if type 1 fimbriae trigger inflammation in the urinary tract. The asymptomatic bacteriuria strain Escherichia coli 83972, which fails to express type 1 fimbriae, due to a 4.25 kb fim B –fim D deletion, was reconstituted with a functional fim gene cluster and fimbrial expression was monitored through a gfp reporter. Each patient was inoculated with the fim + or fim − variants on separate occasions, and the host response to type 1 fimbriae was quantified by intraindividual comparisons of the responses to the fim + or fim − isogens, using cytokines and neutrophils as end‐points. Type 1 fimbriae did not promote inflammation and adherence was poor, as examined on exfoliated cells in urine . This was unexpected, as type 1 fimbriae enhanced the inflammatory response to the same strain in the murine urinary tract and as P fimbrial expression by E. coli 83972 enhances adherence and inflammation in challenged patients. We conclude that type 1 fimbriae do not contribute to the mucosal inflammatory response in the human urinary tract.