ROLE OF GAMMA-INTERFERON IN A NEONATAL MOUSE MODEL OF GROUP-B STREPTOCOCCAL DISEASE

The aim of this study was to assess the role of gamma interferon (IFN- gamma) in a neonatal mouse model of group B streptococcal (GBS) sepsis . IFN-gamma was produced by spleen cells at 24, 48, and 72 h after GBS challenge, Treatment with anti-IFN-gamma at 6 h before challenge tota lly abrogated the IFN-gamma response but did not affect survival. Subc utaneous administration of recombinant IFN-gamma (2,500 IU per pup) at 18 h after challenge resulted in increased survival time and reduced blood colony counts at 48 and 72 h. In vitro preincubation of neonatal whole blood with IFN-gamma before the addition of GBS resulted in sig nificant restriction of bacterial growth. These data indicate that adm inistration of recombinant IFN-gamma can partially restore impaired ho st defenses against GBS in neonatal mice. This cytokine may be useful for the treatment of neonatal infections.