Isolation and identification of the group B streptococcal toxin CM101 from infants with sepsis.

Abstract

To determine whether the group B streptococcal (GBS) polysaccharide exotoxin CM101, which induces a complement-activated cytokine-driven inflammatory response, is present in body fluids of infants with GBS disease. With a sandwich enzyme-linked immunosorbent assay, CM101 was measured in plasma, urine, and cerebrospinal fluid from newborn infants who were evaluated for possible infection and from older infants with culture-confirmed GBS disease. Urine from 11 newborn infants with culture-confirmed early-onset disease contained large amounts of CM101 (1.0 to 5.5 mg/48 h). Plasma concentrations were 62.6 +/- 10.5 microg/mL in these infants and were 69.0 +/- 21.2 microg/mL in 4 older infants with late-onset disease. Plasma CM101 concentrations did not correlate with indexes of illness severity, leukocyte counts, or interleukin-6 or interleukin-8 plasma concentrations. CM101 was present in cerebrospinal fluid of 5 infants with meningitis (8.4 +/- 1.6 microg/mL). CM101 was not found in control samples. CM101 isolated from urine had molecular weight and sugar composition similar to those obtained from GBS culture media, and they both elicited a comparable pathophysiologic response when infused intravenously in lambs. CM101 is present in infants with GBS disease, and it appears to be the same as CM101 obtained from GBS culture media.