Antibody Response to Enterobacterial Lipoprotein of Patients with Varied Infections Due to Enterobacteriaceae

Abstract

The passive hemagglutination test was used to determine the presence of antibodies against the lipoprotein (LP) component of the cell wall of members of the family Enterobacteriaceae in the serum of healthy subjects and of patients with varied enterobacterial infections. LP antibodies were not demonstrated in the serum of healthy children and in only 4% of healthy adults. In contrast, 18% of patients with peritonitis complicating appendicitis, 24% of children with enterobacterial infection of the respiratory tract complicating cystic fibrosis and 42% of patients with enterobacterial bacteremia complicating malignancy had these antibodies. LP antibodies were not detected in the serum of patients with Salmonella or Shigella enteritis or enterobacterial infection of the urinary tract. The specificity of the antibody was documented by the observation that with 10 serum specimens containing antibodies essentially identical titers were obtained with either the murein-lipoprotein or the lipoprotein preparation cleaved from murein as indicator antigens. The reason for these striking differences in the immune response to this common antigen is unknown.