title: Immunogenicity of a whole-cell pertussis vaccine with low lipopolysaccharide content in infants.
abstract: The lack of a clear correlation between the levels of antibody to pertussis antigens and protection against disease lends credence to the possibility that cell-mediated immunity provides primary protection against disease. This phase I comparative trial had the aim of comparing the in vitro cellular immune response and anti-pertussis toxin (anti-PT) immunoglobulin G (IgG) titers induced by a cellular pertussis vaccine with low lipopolysaccharide (LPS) content (wP(low) vaccine) with those induced by the conventional whole-cell pertussis (wP) vaccine. A total of 234 infants were vaccinated at 2, 4, and 6 months with the conventional wP vaccine or the wP(low) vaccine. Proliferation of CD3(+) T cells was evaluated by flow cytometry after 6 days of peripheral blood mononuclear cell culture with stimulation with heat-killed Bordetella pertussis or phytohemagglutinin (PHA). CD3(+), CD4(+), CD8(+), and T-cell receptor gammadelta-positive (gammadelta(+)) cells were identified in the gate of blast lymphocytes. Gamma interferon, tumor necrosis factor alpha, interleukin-4 (IL-4), and IL-10 levels in supernatants and serum anti-PT IgG levels were determined using enzyme-linked immunosorbent assay (ELISA). The net percentage of CD3(+) blasts in cultures with B. pertussis in the group vaccinated with wP was higher than that in the group vaccinated with the wP(low) vaccine (medians of 6.2% for the wP vaccine and 3.9% for the wP(low) vaccine; P = 0.029). The frequencies of proliferating CD4(+), CD8(+), and gammadelta(+) cells, cytokine concentrations in supernatants, and the geometric mean titers of anti-PT IgG were similar for the two vaccination groups. There was a significant difference between the T-cell subpopulations for B. pertussis and PHA cultures, with a higher percentage of gammadelta(+) cells in the B. pertussis cultures (P < 0.001). The overall data did suggest that wP vaccination resulted in modestly better specific CD3(+) cell proliferation, and gammadelta(+) cell expansions were similar with the two vaccines.
authors.affiliation: Center for Investigation in Pediatrics, State University of Campinas Medical School, São Paulo, Brazil.
authors.forename: Tatiane Queiroz
authors.initials: TQ
authors.lastname: Zorzeto
authors.forename: Hisako Gondo
authors.initials: HG
authors.lastname: Higashi
authors.forename: Marcos Tadeu Nolasco
authors.initials: MT
authors.lastname: da Silva
authors.forename: Emilia de Faria
authors.initials: Ede F
authors.lastname: Carniel
authors.forename: Waldely Oliveira
authors.initials: WO
authors.lastname: Dias
authors.forename: Vanessa Domingues
authors.initials: VD
authors.lastname: Ramalho
authors.forename: Taís Nitsch
authors.initials: TN
authors.lastname: Mazzola
authors.forename: Simone Corte Batista Souza
authors.initials: SC
authors.lastname: Lima
authors.forename: André Moreno
authors.initials: AM
authors.lastname: Morcillo
authors.forename: Marco Antonio
authors.initials: MA
authors.lastname: Stephano
authors.forename: Maria Angela Reis de Góes
authors.initials: MA
authors.lastname: Antonio
authors.forename: Maria de Lurdes
authors.initials: Mde L
authors.lastname: Zanolli
authors.forename: Isaias
authors.initials: I
authors.lastname: Raw
authors.forename: Maria Marluce dos Santos
authors.initials: MM
authors.lastname: Vilela
mesh_terms: D000992:Antitoxins / Q000097:blood*; D001886:Bordetella pertussis / Q000276:immunology*; D049109:Cell Proliferation; D016207:Cytokines / Q000378:metabolism; D005260:Female; D006801:Humans; D007117:Immunization, Secondary; D007223:Infant; D008070:Lipopolysaccharides / Q000276:immunology*; D008297:Male; D010567:Pertussis Vaccine / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D000992:Antitoxins; D016207:Cytokines; D008070:Lipopolysaccharides; D010567:Pertussis Vaccine