Abstract
Haemophilus influenzae type b (Hib) capsular polysaccharide (PS) induces protective antibodies but is T independent and poorly immunogenic in infants. Conjugate vaccines of Hib PS linked to proteins, such as CRM(197), increase the PS antibody titer and elicit immunologic memory. To define the conjugate-induced memory T cell response, 19 adults were immunized with Hib-CRM(197), and antibody titers, carrier protein-specific CD4(+) T cell proliferation, and cytokine production were measured. Hib-CRM(197) induced PS and CRM(197) antibodies, vigorous T cell recall responses, and production of cytokines, including interleukin (IL)-2, IL-5, IL-10, and interferon-gamma. There was marked variability in PS antibody titer, despite consistent CRM(197)-specific recall responsiveness, which correlated with peak IgM and IgA PS antibody titers. Correlations were also found between IL-2 and IL-5 and IgA PS antibody levels. Hib-CRM(197) induced a rapid increase in CRM(197)-specific memory T cells and mixed Th1/Th2 cytokines, which may regulate the isotype and quantity of PS antibody.
Publication types
-
Comparative Study
-
Research Support, U.S. Gov't, P.H.S.
MeSH terms
-
Adult
-
Antibodies, Bacterial / blood*
-
Bacterial Capsules
-
Bacterial Proteins / administration & dosage*
-
Bacterial Proteins / immunology
-
Cytokines / blood*
-
Haemophilus Infections / immunology
-
Haemophilus Infections / prevention & control*
-
Haemophilus Vaccines / administration & dosage*
-
Haemophilus Vaccines / immunology
-
Haemophilus influenzae type b* / immunology
-
Humans
-
Immunoglobulin A / blood
-
Immunoglobulin M / blood
-
Immunologic Memory
-
Injections, Subcutaneous
-
Interferon-gamma / blood
-
Interleukins / blood
-
Polysaccharides, Bacterial / administration & dosage*
-
Polysaccharides, Bacterial / immunology
-
Th1 Cells / immunology*
-
Th2 Cells / immunology*
-
Vaccination*
-
Vaccines, Conjugate / administration & dosage
-
Vaccines, Conjugate / immunology
Substances
-
Antibodies, Bacterial
-
Bacterial Proteins
-
Cytokines
-
Haemophilus Vaccines
-
Haemophilus influenzae type b polysaccharide vaccine
-
Immunoglobulin A
-
Immunoglobulin M
-
Interleukins
-
Polysaccharides, Bacterial
-
Vaccines, Conjugate
-
CRM197 (non-toxic variant of diphtheria toxin)
-
Interferon-gamma