Schaffzin JK, Stringer JR; Keystone Symposia on Molecular and Cellular Biology:1998 Opportunistic Infections in AIDS.
Keyst Symp Mol Cell Biol Keyst Symp Mol Cell Biol. 1998 Apr 2-8; 114 (abstract no. 110).
Department of Molecular Genetics, University of Cincinnati College of Medicine, OH.
Pneumocystis carinii is an opportunistic fungus that causes potentially fatal pneumonia in immunosuppressed patients. Single populations of P. carinii display numerous different antigenic forms of their Major Surface Glycoprotein (MSG). MSGs constitute a large gene family encoding a diverse family of proteins. It is believed that observed antigenic variability is due to the expression of different MSG isoforms by a single strain of organism rather than a result of strain variation. To describe this phenomenon, we utilized a monoclonal antibody, RA-C11, which recognizes a 116kDa band on whole-P. carinii western blots assumed to be MSG. Furthermore, RA-C11 was demonstrated previously to react differentially with P. carinii populations. By expression cloning and Southern and Western blotting, we demonstrated that RA-C11 recognizes a specific MSG isoform. We also showed that RA-C11 reactivity with MSG varies greatly among populations. Specifically, 50-fold reduction was seen between the populations with greatest and least RA-C11 reactivity. However, two other populations showed intermediate reactivity, approximately 5-10 fold less than the population with the greatest RA-C11 reactivity. Thus, expression of any given MSG epitope occurs at different levels in different populations. This is the first quantitative description of antigenic variability in P. carinii populations.
Publication Types:
Keywords:
- Antibodies, Monoclonal
- Antigenic Variation
- Cloning, Molecular
- DNA, Complementary
- Epitopes
- Gene Expression
- Gene Expression Regulation, Fungal
- Humans
- Membrane Glycoproteins
- Pneumocystis carinii
- genetics
- immunology
Other ID:
UI: 102236506
From Meeting Abstracts