ABSTRACT
This study was undertaken to assess whether glycolipid antigens (particularly gangliosides) are associated with Pneumocystis carinii obtained from human lungs. Gangliosides were extracted, purified in high performance thin-layer chromatography and stained with resorcinol. Two resorcinol-positive bands, co-migrating with GM1 and GD1a were demonstrated, suggesting the existence of ganglioside molecules on P. carinii. No resorcinol-positive bands were revealed in the pulmonary control tissue. In addition, an antiserum obtained from rabbits immunized with P. carinii antigen reacted with gangliosides GM1 and GD1a, as revealed by a dot immunobinding assay. This reactivity was inhibited by first incubating the antiserum with ganglioside micelles. Furthermore, anti-glycosphingolipid antibodies (aGM1) reacted with the bands of 200 and 55 kDa of P. carinii antigen. These results suggest that ganglioside antigens expressed on P. carinii can trigger specific immune responses.
Subject(s)
Acquired Immunodeficiency Syndrome/complications , Gangliosides/analysis , Lung/microbiology , Pneumocystis/chemistry , Pneumonia, Pneumocystis/microbiology , Acquired Immunodeficiency Syndrome/microbiology , Antibodies, Fungal/immunology , Antigens, Fungal/analysis , Blotting, Western , Chromatography, Thin Layer , Electrophoresis, Polyacrylamide Gel , Gangliosides/immunology , Humans , Immune Sera/immunology , Immunoblotting , Opportunistic Infections/complications , Opportunistic Infections/microbiology , Pneumocystis/immunology , Pneumonia, Pneumocystis/complicationsABSTRACT
Lipopolysaccharide (LPS) of Salmonella typhi has been analyzed by immunoblotting with pooled sera from typhoid patients. Pooled typhoid sera have recognized all the antigenic determinants of S. typhi LPS, giving a strong reaction with the repeating units on the O-side chains as well as with the core region. Cross-reacting antigens have been observed with the LPS of S. typhimurium and S. enteritidis, while no heterologous reactions were seen with the LPS of E. coli strains.
