title: Memory B cell and other immune responses in children receiving two doses of an oral killed cholera vaccine compared to responses following natural cholera infection in Bangladesh.
abstract: Current oral cholera vaccines induce lower protective efficacy and shorter duration of protection against cholera than wild-type infection provides, and this difference is most pronounced in young children. Despite this, there are limited data comparing immune responses in children following wild-type disease versus vaccination, especially with regard to memory responses associated with long-term immunity. Here, we report a comparison of immune responses in young children (2 to 5 years of age; n = 20) and older children (6 to 17 years of age; n = 20) given two doses of an oral killed cholera vaccine containing recombinant cholera toxin B subunit (CtxB) 14 days apart and compare these responses to those induced in similarly aged children recovering from infection with Vibrio cholerae O1 Ogawa in Bangladesh. We found that the two vaccine groups had comparable vibriocidal and lipopolysaccharide (LPS)-specific plasma antibody responses. Vaccinees developed lower levels of IgG memory B cell (MBC) responses against CtxB but no significant MBC responses against LPS. In contrast, children recovering from natural cholera infection developed prominent LPS IgG and IgA MBC responses, as well as CtxB IgG MBC responses. Plasma LPS IgG, IgA, and IgM responses, as well as vibriocidal responses, were also significantly higher in children following disease than after vaccination. Our findings suggest that acute and memory immune responses following oral cholera vaccination in children are significantly lower than those observed following wild-type disease, especially responses targeting LPS. These findings may explain, in part, the lower efficacy of oral cholera vaccination in children.
authors.affiliation: Centre for Vaccine Sciences, Bangladesh, Dhaka, Bangladesh. dleung@partners.org
authors.forename: Daniel T
authors.initials: DT
authors.lastname: Leung
authors.forename: Mohammad Arif
authors.initials: MA
authors.lastname: Rahman
authors.forename: M
authors.initials: M
authors.lastname: Mohasin
authors.forename: Sweta M
authors.initials: SM
authors.lastname: Patel
authors.forename: Amena
authors.initials: A
authors.lastname: Aktar
authors.forename: Farhana
authors.initials: F
authors.lastname: Khanam
authors.forename: Taher
authors.initials: T
authors.lastname: Uddin
authors.forename: M Asrafuzzaman
authors.initials: MA
authors.lastname: Riyadh
authors.forename: Amit
authors.initials: A
authors.lastname: Saha
authors.forename: Mohammad Murshid
authors.initials: MM
authors.lastname: Alam
authors.forename: Fahima
authors.initials: F
authors.lastname: Chowdhury
authors.forename: Ashraful Islam
authors.initials: AI
authors.lastname: Khan
authors.forename: Richelle
authors.initials: R
authors.lastname: Charles
authors.forename: Regina
authors.initials: R
authors.lastname: LaRocque
authors.forename: Jason B
authors.initials: JB
authors.lastname: Harris
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Calderwood
authors.forename: Firdausi
authors.initials: F
authors.lastname: Qadri
authors.forename: Edward T
authors.initials: ET
authors.lastname: Ryan
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000367:Age Factors; D000907:Antibodies, Bacterial / Q000097:blood; D001402:B-Lymphocytes / Q000276:immunology*; D001459:Bangladesh; D001770:Blood Bactericidal Activity; D002648:Child; D002675:Child, Preschool; D002771:Cholera / Q000276:immunology*; D022121:Cholera Vaccines / Q000008:administration & dosage / Q000276:immunology*; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007156:Immunologic Memory; D008297:Male; D014611:Vaccination / Q000379:methods*; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000276:immunology; D041241:Vibrio cholerae O1 / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D022121:Cholera Vaccines; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D015164:Vaccines, Inactivated