Induction of Systemic Antifimbria and Antitoxin Antibody Responses in Egyptian Children and Adults by an Oral, Killed Enterotoxigenic
            <i>Escherichia coli</i>
            plus Cholera Toxin B Subunit Vaccine

Hall, Eric R.; Wierzba, Thomas F.; Åhrén, Christina; Rao, Malla R.; Bassily, S.; Francis, Wagdy; Girgis, Fouad Y.; Safwat, M. S. A.; Lee, Young Jong; Svennerholm, Ann‐Mari; Clemens, John D.; Savarino, Stephen J.

doi:10.1128/iai.69.5.2853-2857.2001

Cited by 46 publications

(18 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this study, the decline in the rate of infection with ETEC isolates expressing CFA/I that was seen supports this idea and underlies the importance of ETEC vaccine development, as the risk factors for acquiring ETEC infection are present at higher levels among children up to 24 months of age (5,29). ETEC class 5 fimbriae, in particular, CFA/I and CS14, in addition to the CS5 and CS7 antigens, were shown to elicit cross-reactive immune responses in primed children (13). It is interesting to note that of the CF-expressing ETEC isolates, 72% were of a type (CFA/I, CS1, CS2, CS3, CS4, CS5, and CS6) capable of inducing an antifimbrial immune response (9,28).…”

Section: Discussionsupporting

confidence: 56%

Phenotypic and Genotypic Analysis of Enterotoxigenic Escherichia coli in Samples Obtained from Egyptian Children Presenting to Referral Hospitals

et al. 2009

View full text Add to dashboard Cite

Hospital surveillance was established in the Nile River Delta to increase the understanding of the epidemiology of diarrheal disease among Egyptian children. Between September 2000 and August 2003, samples obtained from children less than 5 years of age who had diarrhea and who were seeking hospital care were cultured for enteric bacteria. Colonies from each culture with a morphology typical of that of Escherichia coli were tested for the heat-labile (LT) and heat-stable (ST) toxins by a GM-1-specific enzyme-linked immunosorbent assay and colonization factor (CF) antigens by an immunodot blot assay. Enterotoxigenic E. coli (ETEC) isolates were recovered from 320/1,540 (20.7%) children, and ETEC isolates expressing a known CF were identified in 151/320 (47%) samples. ST CFA/I, ST CS6, ST CS14, and LT and ST CS5 plus CS6 represented 75% of the CFs expressed by ETEC isolates expressing a detectable CF. Year-to-year variability in the proportion of ETEC isolates that expressed a detectable CF was observed (e.g., the proportion that expressed CFA/I ranged from 10% in year 1 to 21% in year 3); however, the relative proportions of ETEC isolates expressing a CF were similar over the reporting period. The proportion of CF-positive ETEC isolates was higher among isolates that expressed ST. ETEC isolates expressing CS6 were isolated significantly less often (P < 0.001) than isolates expressing CFA/I in children less than 1 year of age. Macrorestriction profiling of CFA/I-expressing ETEC isolates by using the restriction enzyme XbaI and pulsed-field gel electrophoresis demonstrated a wide genetic diversity among the isolates that did not directly correlate with the virulence of the pathogen. The genome plasticity demonstrated in the ETEC isolates collected in this work suggests an additional challenge to the development of a globally effective vaccine for ETEC.

show abstract

Section: Discussionsupporting

confidence: 56%

Phenotypic and Genotypic Analysis of Enterotoxigenic Escherichia coli in Samples Obtained from Egyptian Children Presenting to Referral Hospitals

et al. 2009

View full text Add to dashboard Cite

show abstract

“…Sera were collected on days 0, 5, 7, 10, 14, and 28. The IgA and IgG antibody titers against LT were determined by the GM 1 enzyme-linked immunosorbent assay (ELISA) method (27,53), and the titers against CFA/I and CS6 were determined by an ELISA as previously described (22,52). The endpoint titers were defined as the interpolated dilutions of the samples giving an absorbance at 450 nm that was 0.4 absorbance unit above the background value.…”

Section: Methodsmentioning

confidence: 99%

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

et al. 2007

View full text Add to dashboard Cite

In order to test vaccines against enterotoxigenic Escherichia coli (ETEC)-10 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 ( Enterotoxigenic Escherichia coli (ETEC)-induced diarrhea is recognized frequently in individuals who travel in developing countries around the world (4,7,8,26,29,47) and is a major medical problem for military personnel deployed in these countries (26,44,45). Since strict personal hygiene and avoidance of local water and fresh and undercooked foods are recommendations with which travelers have difficulty complying, other means to reduce the ETEC attack rate must be considered. The use of short-term chemoprophylaxis and self-treatment for diarrhea are effective for travelers who are unwilling to accept even a short period of illness because of the serious impact it would have on their overall mission. However, the routine use of antimicrobial prophylaxis for the general traveler is not recommended because of the potential for associated adverse drug reactions and the potential to worsen the problem of antibiotic resistance of enteric bacteria (8,25,29,43,47). These factors make development of vaccines against ETEC a priority.

show abstract

“…A formalin-inactivated whole-cell vaccine produced by SBL Vaccin, Stockholm, Sweden, contains a variety of strains with many of the common CFAs and the B subunit of cholera toxin (CT), which is structurally similar to, and gives cross-protection against, ETEC LT. This vaccine was immunogenic in several adult and pediatric populations (1,9,11,17,18,25). In a study of 685 U.S. citizens traveling to Mexico and Guatemala, the vaccine protected against moderate to severe ETEC illness (protective efficacy of 77%, P ϭ a Antibody levels were measured by time-resolved fluorescence.…”

Section: Discussionmentioning

confidence: 99%

“…Then, 1-ml aliquots were cultured in 24-well tissue culture plates for 48 h, and the supernatants were harvested and stored frozen at Ϫ20°C until assayed for anti-CFA IgG and IgA antibodies by enzyme-linked immunosorbent assay (ELISA). IgA and IgG antibodies in serum and ALS and IgA antibodies in fecal extracts were measured by ELISA as previously described (1,9). Samples were threefold serially diluted in duplicate in microtiter plates, and endpoint titers were determined as the reciprocal interpolated dilutions giving an A 405 of 0.4 above the background.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Comparative Safety and Immunogenicity of Two Attenuated Enterotoxigenic Escherichia coli Vaccine Strains in Healthy Adults

et al. 2006

View full text Add to dashboard Cite

A vaccine against enterotoxigenic Escherichia coli (ETEC) is needed to prevent diarrheal illness among children in developing countries and at-risk travelers. Two live attenuated ETEC strains, PTL002 and PTL003, which express the ETEC colonization factor CFA/II, were evaluated for safety and immunogenicity. In a randomized, double-blind, placebo-controlled trial, 19 subjects ingested one dose, and 21 subjects ingested two doses (days 0 and 10) of PTL-002 or PTL-003 at 2 ؋ 10 9 CFU/dose. Anti-CFA/II mucosal immune responses were determined from the number of antibody-secreting cells (ASC) in blood measured by enzyme-linked immunospot assay, the antibody in lymphocyte supernatants (ALS) measured by enzyme-linked immunosorbent assay (ELISA), and fecal immunoglobulin A (IgA) levels determined by ELISA. Time-resolved fluorescence (TRF) ELISA was more sensitive than standard colorimetric ELISA for measuring serum antibody responses to CFA/II and its components, CS1 and CS3. Both constructs were well tolerated. Mild diarrhea occurred after 2 of 31 doses (6%) of PTL-003. PTL-003 produced more sustained intestinal colonization than PTL-002 and better IgA response rates: 90% versus 55% (P ‫؍‬ 0.01) for anti-CFA/II IgA-ASCs, 55% versus 30% (P ‫؍‬ 0.11) for serum anti-CS1 IgA by TRF, and 65% versus 25% (P ‫؍‬ 0.03) for serum anti-CS3 IgA by TRF. Serum IgG response rates to CS1 or CS3 were 55% in PTL-003 recipients and 15% in PTL-002 recipients (P ‫؍‬ 0.02). Two doses of either strain were not significantly more immunogenic than one. Based on its superior immunogenicity, which was comparable to that of a virulent ETEC strain and other ETEC vaccine candidates, PTL-003 will be developed further as a component of a live, oral attenuated ETEC vaccine.

show abstract

Induction of Systemic Antifimbria and Antitoxin Antibody Responses in Egyptian Children and Adults by an Oral, Killed Enterotoxigenic Escherichia coli plus Cholera Toxin B Subunit Vaccine

Cited by 46 publications

References 20 publications

Phenotypic and Genotypic Analysis of Enterotoxigenic Escherichia coli in Samples Obtained from Egyptian Children Presenting to Referral Hospitals

Phenotypic and Genotypic Analysis of Enterotoxigenic Escherichia coli in Samples Obtained from Egyptian Children Presenting to Referral Hospitals

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

Comparative Safety and Immunogenicity of Two Attenuated Enterotoxigenic Escherichia coli Vaccine Strains in Healthy Adults

Contact Info

Product

Resources

About