IL-12-mediated increases in protection elicited by pneumococcal and meningococcal conjugate vaccines.
Interleukin-12 (IL-12) may be a beneficial adjuvant for augmenting vaccine efficacy against encapsulated bacteria such as Streptococcus pneumoniae and Neisseria meningitidis since it can stimulate production of interferon-gamma (IFN-gamma) and secretion of antibody isotypes that are efficient at mediating complement fixation and opsonophagocytosis. In this study, we demonstrate the ability of IL-12 to enhance murine antibody responses, particularly IgG2a levels, to both pneumococcal and meningococcal conjugate vaccines. Transfer of immune serum from mice immunized with the meningococcal conjugate vaccine and IL-12 resulted in increased survival times, whereas transfer of serum from mice immunized with the pneumococcal conjugate and IL-12 resulted in protection from death upon bacterial challenge. Although treatment with vaccine and IL-12 increased levels of IFN-gamma mRNA, IL-12-mediated enhancement of antibody responses still occurred in IFN-gamma(-/-) mice. The results demonstrate the effectiveness of IL-12 as an adjuvant for polysaccharide conjugate vaccines, especially the pneumococcal conjugate vaccine.
Department of Microbiology and Immunology, Medical College of Ohio, Toledo 43614, USA.
R M
RM
Buchanan
D E
DE
Briles
B P
BP
Arulanandam
M A
MA
Westerink
R H
RH
Raeder
D W
DW
Metzger
D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics; D007116:Immunization, Passive; D007074:Immunoglobulin G / Q000096:biosynthesis; D007371:Interferon-gamma / Q000172:deficiency / Q000235:genetics; D018664:Interleukin-12 / Q000008:administration & dosage*; D022401:Meningococcal Vaccines / Q000008:administration & dosage*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D022242:Pneumococcal Vaccines / Q000008:administration & dosage*; D018074:Vaccines, Conjugate / Q000008:administration & dosage
D000907:Antibodies, Bacterial; D017931:DNA Primers; D007074:Immunoglobulin G; D022401:Meningococcal Vaccines; D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate; D018664:Interleukin-12; D007371:Interferon-gamma; D007041:Hypoxanthine Phosphoribosyltransferase