scholarly journals Infection with colonization factor antigen I-expressing enterotoxigenic Escherichia coli boosts antibody responses against heterologous colonization factors in primed subjects

1997 ◽  
Vol 119 (3) ◽  
pp. 391-393 ◽  
Author(s):  
A. RUDIN ◽  
G. WIKLUND ◽  
C. WENNERÅS ◽  
F. QADRI
Keyword(s):  
Escherichia Coli ◽  
Antibody Responses ◽  
Enterotoxigenic Escherichia Coli ◽  
Enzyme Linked Immunosorbent Assay ◽  
Symptomatic Infection ◽  
Colonization Factor ◽  
Serum Iga ◽  
Iga Antibody ◽  
Colonization Factors ◽  
Colonization Factor Antigen I

Enterotoxigenic Escherichia coli (ETEC) adhere to the intestinal mucosa by a number of fimbrial colonization factors (CFs) that have been claimed to induce only type-specific immunity. However, adult Bangladeshi patients infected with CFA/I-expressing bacteria, developed significant plasma IgA antibody responses, as determined by enzyme-linked immunosorbent assay, not only against the homologous fimbriae but also against several heterologous CFs, i.e. CS1, CS2, CS4 and PCFO166 fimbriae. In contrast, North American volunteers, who had probably not been infected by ETEC previously, responded with serum IgA against CFA/I fimbriae but not against any other CFs after symptomatic infection with CFA/I-expressing ETEC. Thus, infection with CFA/I-expressing bacteria may boost immune responses against CFs with a related amino acid sequence in previously primed subjects.

scholarly journals The Major Subunit, CfaB, of Colonization Factor Antigen I from Enterotoxigenic Escherichia coli Is a Glycosphingolipid Binding Protein

2006 ◽  
Vol 74 (6) ◽  
pp. 3488-3497 ◽  
Author(s):  
Lena Jansson ◽  
Joshua Tobias ◽  
Michael Lebens ◽  
Ann-Mari Svennerholm ◽  
Susann Teneberg
Keyword(s):  
Escherichia Coli ◽  
Pathogenic Bacteria ◽  
Binding Capacity ◽  
Enterotoxigenic Escherichia Coli ◽  
E Coli ◽  
Colonization Factor ◽  
Mucosal Surfaces ◽  
Colonization Factors ◽  
Bacteria Adhesion ◽  
Colonization Factor Antigen I

ABSTRACT Bacterial adherence to mucosal surfaces is an important virulence trait of pathogenic bacteria. Adhesion of enterotoxigenic Escherichia coli (ETEC) to the intestine is mediated by a number of antigenically distinct colonization factors (CFs). One of the most common CFs is CFA/I. This has a fimbrial structure composed of a major repeating subunit, CfaB, and a single tip subunit, CfaE. The potential carbohydrate recognition by CFA/I was investigated by binding CFA/I-fimbriated bacteria and purified CFA/I fimbriae to a large number of variant glycosphingolipids separated on thin-layer chromatograms. For both fimbriated bacteria and purified fimbriae, specific interactions could be identified with a number of nonacid glycosphingolipids. These included glucosylceramide, lactosylceramide with phytosphingosine and/or hydroxy fatty acids, neolactotetraosylceramide, gangliotriaosylceramide, gangliotetraosylceramide, the H5 type 2 pentaglycosylceramide, the Lea-5 glycosphingolipid, the Lex-5 glycosphingolipid, and the Ley-6 glycosphingolipid. These glycosphingolipids were also recognized by recombinant E. coli expressing CFA/I in the absence of tip protein CfaE, as well as by purified fimbriae from the same strain. This demonstrates that the glycosphingolipid-binding capacity of CFA/I resides in the major CfaB subunit.

scholarly journals Intestinal Immune Responses to an Inactivated Oral Enterotoxigenic Escherichia coli Vaccine and Associated Immunoglobulin A Responses in Blood

1998 ◽  
Vol 66 (7) ◽  
pp. 3311-3316 ◽  
Author(s):  
Christina Åhrén ◽  
Marianne Jertborn ◽  
Ann-Mari Svennerholm
Keyword(s):  
Escherichia Coli ◽  
Immune Responses ◽  
Serum Antibody ◽  
Immunoglobulin A ◽  
Lavage Fluid ◽  
Antibody Responses ◽  
Enterotoxigenic Escherichia Coli ◽  
Antibody Secreting Cell ◽  
Colonization Factor ◽  
Iga Antibody

ABSTRACT An inactivated oral enterotoxigenic Escherichia coli(ETEC) vaccine against ETEC diarrhea was given to 25 adult Swedish volunteers. The vaccine consisted of formalin-killed E. coli bacteria expressing the most common colonization factor antigens (CFAs), i.e., CFA/I, -II, and -IV, and recombinantly produced cholera B subunit (CTB). Immunoglobulin A (IgA) antibody responses in intestinal lavage fluid to CTB and CFAs were determined and compared with corresponding responses in stool extracts and serum as well as with IgA antibody-secreting cell (ASC) responses in peripheral blood. Two doses of vaccine induced significant IgA responses to the different CFAs in lavage fluid in 61 to 87% of the vaccinees and in stool in 38 to 81% of them. The most frequent responses were seen against CFA/I. The magnitudes of the antibody responses against CTB and CFA/I in stool correlated significantly (CTB,P < 0.01; CFA/I, P < 0.05) with those in intestinal lavage. Intestinal lavage responses against CFAs were best reflected by the ASC responses, with the sensitivity of the ASC assay being 80 to 85%, followed by stool (sensitivity of 50 to 88%) and serum antibody (sensitivity of 7 to 65%) analyses. CTB-specific immune responses were seen in >90% of the vaccinees in all assays.

scholarly journals Evaluation of the Immunogenicity and Protective Efficacy of an Enterotoxigenic Escherichia coli CFA/I Adhesin–Heat-Labile Toxin Chimera

2020 ◽  
Vol 88 (11) ◽  
Author(s):  
Aisling O'Dowd ◽  
Milton Maciel ◽  
Steven T. Poole ◽  
Michael G. Jobling ◽  
Julianne E. Rollenhagen ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Protective Efficacy ◽  
Antibody Responses ◽  
Enterotoxigenic Escherichia Coli ◽  
Content Type ◽  
B Subunit ◽  
Colonization Factor ◽  
Heat Labile ◽  
Intestinal Adhesion ◽  
Colonization Factors

ABSTRACT Recent efforts to develop an enterotoxigenic Escherichia coli (ETEC) vaccine have focused on the antigenically conserved tip adhesins of colonization factors. We showed previously that intranasal immunization with dsc19CfaE, a soluble variant of the in cis donor strand-complemented tip adhesin of a colonization factor of the class 5 family (CFA/I) fimbria, is highly immunogenic and protects against oral challenge with CFA/I-positive (CFA/I+) ETEC strain H10407 in the Aotus nancymaae nonhuman primate. We also reported a cholera toxin (CT)-like chimera (called dsc19CfaE-CTA2/CTB) in which the CTA1 domain of CT was replaced by dsc19CfaE that was strongly immunogenic when administered intranasally or orogastrically in mice. Here, we evaluate the immunogenicity and protective efficacy (PE) of a refined and more stable chimera comprised of a pentameric B subunit of ETEC heat-labile toxin (LTB) in lieu of the CTB pentamer and a donor strand truncation (dsc14) of CfaE. The refined chimera, dsc14CfaE-sCTA2/LTB, was highly immunogenic in mice when administered intranasally or intradermally, eliciting serum and fecal antibody responses against CfaE and LTB, as well as strong hemagglutination inhibition titers, a surrogate for neutralization of intestinal adhesion mediated by CfaE. Moreover, the chimera was safe and highly immunogenic when administered intradermally to guinea pigs. In A. nancymaae, intradermal (i.d.) immunization with chimera plus single-mutant heat-labile toxin [LT(R192G)] elicited strong serum anti-CfaE and anti-LTB antibody responses and conferred significant reduction of diarrhea compared to phosphate-buffered saline (PBS) controls (PE = 84.1%; P < 0.02). These data support the further evaluation of dsc14CfaE-sCTA2/LTB as an ETEC vaccine in humans.

scholarly journals Immune Response, Ciprofloxacin Activity, and Gender Differences after Human Experimental Challenge by Two Strains of Enterotoxigenic Escherichia coli

2006 ◽  
Vol 75 (1) ◽  
pp. 252-259 ◽  
Author(s):  
T. S. Coster ◽  
M. K. Wolf ◽  
E. R. Hall ◽  
F. J. Cassels ◽  
D. N. Taylor ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Immune Responses ◽  
Immunoglobulin A ◽  
Enterotoxigenic Escherichia Coli ◽  
Antibody Secreting Cell ◽  
E Coli ◽  
Immunological Responses ◽  
Colonization Factor ◽  
Colonization Factors ◽  
Colonization Factor Antigen I

ABSTRACT In order to test vaccines against enterotoxigenic Escherichia coli (ETEC)-induced diarrhea, challenge models are needed. In this study we compared clinical and immunological responses after North American volunteers were orally challenged by two ETEC strains. Groups of approximately eight volunteers received 109 or 1010 CFU of E. coli B7A (LT+ ST+ CS6+) or 108 or 109 CFU of E. coli H10407 (LT+ ST+ CFA/I+). About 75% of the volunteers developed diarrhea after challenge with 1010 CFU B7A or either dose of H10407. B7A had a shorter incubation period than H10407 (P = 0.001) and caused milder illness; the mean diarrheal output after H10407 challenge was nearly twice that after B7A challenge (P = 0.01). Females had more abdominal complaints, and males had a higher incidence of fever. Ciprofloxacin generally diminished or stopped symptoms and shedding by the second day of antibiotic treatment, but four subjects shed for one to four additional days. The immune responses to colonization factors CS6 and colonization factor antigen I (CFA/I) and to heat-labile toxin (LT) were measured. The responses to CFA/I were the most robust responses; all volunteers who received H10407 had serum immunoglobulin A (IgA) and IgG responses, and all but one volunteer had antibody-secreting cell (ASC) responses. One-half the volunteers who received B7A had an ASC response to CS6, and about one-third had serum IgA or IgG responses. Despite the differences in clinical illness and immune responses to colonization factors, the immune responses to LT were similar in all groups and were intermediate between the CFA/I and CS6 responses. These results provide standards for immune responses after ETEC vaccination.

Sign in / Sign up

Export Citation Format

Share Document