DOI Seite / Zitierlink:
https://doi.org/10.11588/diglit.48120#0082
64 Molecular and Cell Biology of Autoantibodies and Autoimmunity
Comparable results were obtained by immunization of mice with DNA from
Micrococcus lysodeikticus. Together, these studies indicate that bacterial DNA
contains regions that can be the target of antibody responses likely because they
are rarely expressed in mammalian DNA. These regions could serve as a trigger
for an anti-DNA response in SLE by a process of molecular mimicry.
The Binding of Anti-La Antibodies to Fusion Proteins Containing
Various La Epitopes
D. S. Pisetsky, J. D. Keene, and E. W. St. Clair
Division of Rheumatology and Immunology, Duke University Medical Center, Durham,
NC 27705, USA
To investigate the mechanisms underlying the anti-La autoantibody response,
the fine specificity of anti-La antibodies was assessed using a series of recom-
binantly derived fusion proteins containing various portions of the La molecule.
Using solid phase ELISAs, anti-La positive sera of patients with a variety of con-
nective tissue diseases bound to fusion proteins representing the middle (LaC) as
well as amino (LaA) and carboxyl (LaD) terminal portions of the La molecule.
The quantitative binding to the different La fragments was independent of diag-
nosis and variable among patients with the same diagnosis. Affinity chromatog-
raphy using solubilized fusion proteins attached to Sepharose indicated that an-
tibodies binding to the different fragments were independent populations; thus,
antibodies binding to a LaC column bound poorly to LaA or LaD by ELISA.
Analysis of sequential sera of individuals indicated that antibody levels to the dif-
ferent fragments varied in parallel. Together, these observations suggest that anti-
La antibodies recognize multiple epitopes on the La antigen and arise as an im-
mune response to the La molecule itself.
Comparable results were obtained by immunization of mice with DNA from
Micrococcus lysodeikticus. Together, these studies indicate that bacterial DNA
contains regions that can be the target of antibody responses likely because they
are rarely expressed in mammalian DNA. These regions could serve as a trigger
for an anti-DNA response in SLE by a process of molecular mimicry.
The Binding of Anti-La Antibodies to Fusion Proteins Containing
Various La Epitopes
D. S. Pisetsky, J. D. Keene, and E. W. St. Clair
Division of Rheumatology and Immunology, Duke University Medical Center, Durham,
NC 27705, USA
To investigate the mechanisms underlying the anti-La autoantibody response,
the fine specificity of anti-La antibodies was assessed using a series of recom-
binantly derived fusion proteins containing various portions of the La molecule.
Using solid phase ELISAs, anti-La positive sera of patients with a variety of con-
nective tissue diseases bound to fusion proteins representing the middle (LaC) as
well as amino (LaA) and carboxyl (LaD) terminal portions of the La molecule.
The quantitative binding to the different La fragments was independent of diag-
nosis and variable among patients with the same diagnosis. Affinity chromatog-
raphy using solubilized fusion proteins attached to Sepharose indicated that an-
tibodies binding to the different fragments were independent populations; thus,
antibodies binding to a LaC column bound poorly to LaA or LaD by ELISA.
Analysis of sequential sera of individuals indicated that antibody levels to the dif-
ferent fragments varied in parallel. Together, these observations suggest that anti-
La antibodies recognize multiple epitopes on the La antigen and arise as an im-
mune response to the La molecule itself.