Antigen-Specific Memory B-cell Responses to Enterotoxigenic Escherichia coli Infection in Bangladeshi Adults
Year: 2014
Type: article
Study design: Observational Study
Abstract: BACKGROUND: Multiple infections with diverse enterotoxigenic E. coli (ETEC) strains lead to broad spectrum protection against ETEC diarrhea. However, the precise mechanism of protection against ETEC infection is still unknown. Therefore, memory B cell responses and affinity maturation of antibodies to the specific ETEC antigens might be important to understand the mechanism of protection. METHODOLOGY: In this study, we investigated the heat labile toxin B subunit (LTB) and colonization factor antigens (CFA/I and CS6) specific IgA and IgG memory B cell responses in Bangladeshi adults (n = 52) who were infected with ETEC. We also investigated the avidity of IgA and IgG antibodies that developed after infection to these antigens. PRINCIPAL FINDINGS: Patients infected with ETEC expressing LT or LT+heat stable toxin (ST) and CFA/I group or CS6 colonization factors developed LTB, CFA/I or CS6 specific memory B cell responses at day 30 after infection. Similarly, these patients developed high avidity IgA and IgG antibodies to LTB, CFA/I or CS6 at day 7 that remained significantly elevated at day 30 when compared to the avidity of these specific antibodies at the acute stage of infection (day 2). The memory B cell responses, antibody avidity and other immune responses to CFA/I not only developed in patients infected with ETEC expressing CFA/I but also in those infected with ETEC expressing CFA/I cross-reacting epitopes. We also detected a significant positive correlation of LTB, CFA/I and CS6 specific memory B cell responses with the corresponding increase in antibody avidity. CONCLUSION: This study demonstrates that natural infection with ETEC induces memory B cells and high avidity antibodies to LTB and colonization factor CFA/I and CS6 antigens that could mediate anamnestic responses on re-exposure to ETEC and may help in understanding the requirements to design an effective vaccination strategies.
Source: PLoS neglected tropical diseases
Authors: Mohammad Murshid Alam, Amena Aktar, Sadia Afrin, Mohammad Arif Rahman, Sarmin Aktar, Taher Uddin, M. Arifur Rahman, Deena Al Mahbuba, Fahima Chowdhury, Ashraful Islam Khan, Taufiqur Rahman Bhuiyan, Yasmin Ara Begum, Edward T. Ryan, Stephen B. Calderwood, Ann-Mari Svennerholm, Firdausi Qadri
Language: English
Subfield: Endocrinology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,670
Awards: Protecutive immunity to human cholera in Bangladesh, High throughput NAPPA-proteoimmunomics and Vibrio cholerae vaccine development, G1510978416, G1873111418, Vaccination against Shigella and ETEC: novel antigens, novel approaches, O-Specific Polysaccharide Responses and Cholera, G3472663962, G3769145211, G4497380281, G516757433, G5551172042, G647409134, O-Specific Polysaccharide Responses and Cholera, G9000044515, O-Specific Polysaccharide Responses and Cholera, International research training program in vaccine development and public health
OpenAlex ID: W2147440419