DOI Seite / Zitierlink:
https://doi.org/10.11588/diglit.48120#0041
Abstracts
23
and host self-components referred to as molecular mimicry. A self-antigen target
for anti-(Ul)snRNP autoantibodies which are characteristic for certain inflam-
matory rheumatic diseases is a particle-associated 68 kDa protein (p68). The cor-
responding gene has been cloned and three major autoantigenic domains have
been identified. One of the antigenic domains (domain A) shows sequence
similarity to group specific nucleocapsid proteins (gag-protein) of animal
retroviruses and this led to the speculation that similar human viruses play a role
in initiation of p68 autoimmune response.
To investigate the significance of this sequence similarity with retroviral se-
quences, to determine whether there is more than one epitope in this region, and
to identify the amino acids involved in autoantibody binding, detailed epitope
mapping and search for shared epitopes with other sequences have been per-
formed.
Wildtype and mutant domain A polypeptide sequences expressed as fusion
proteins in E. coli or synthetic peptides derived from domain A were used as
substrates in immunoblotting and ELISA assays. According to the reaction pat-
terns of a collection of anti-p68 autoantibody positive sera three groups of sera
were identified: group I contained antibodies binding to a sequence 20 amino
acids long which presumably represents a discontinuous epitope; group II sera
reacted with a five amino acid motif and group III sera contained both of these
antibody specificities. The 5 amino acid sequence motif was also found on a pro-
tein of a highly prevalent human pathogenic virus. Crossreaction of the p68 au-
toantibody with the 5 amino acid sequence motif in the viral sequence context
could be demonstrated with antibodies affinity purified from domain A contain-
ing fusion proteins. The common epitope recognized by antibodies of autoim-
mune sera suggests that these human viruses may play a role in initiation of
autoimmunity to the well-known p68 antigen. This working hypothesis is current-
ly under investigation.
Human Autoantibodies to Synaptonemal Complex
T. Haaf, A. Machens, and M. Schmid
Department of Human Genetics, University of Wurzburg, Wurzburg, FRG
Autoantibodies to synaptonemal complex (SC) are spontaneously produced
by patients with various autoimmune diseases. The synaptonemal complex forms
the proteinaceous axis between pairing chromosomes during meiotic prophase;
23
and host self-components referred to as molecular mimicry. A self-antigen target
for anti-(Ul)snRNP autoantibodies which are characteristic for certain inflam-
matory rheumatic diseases is a particle-associated 68 kDa protein (p68). The cor-
responding gene has been cloned and three major autoantigenic domains have
been identified. One of the antigenic domains (domain A) shows sequence
similarity to group specific nucleocapsid proteins (gag-protein) of animal
retroviruses and this led to the speculation that similar human viruses play a role
in initiation of p68 autoimmune response.
To investigate the significance of this sequence similarity with retroviral se-
quences, to determine whether there is more than one epitope in this region, and
to identify the amino acids involved in autoantibody binding, detailed epitope
mapping and search for shared epitopes with other sequences have been per-
formed.
Wildtype and mutant domain A polypeptide sequences expressed as fusion
proteins in E. coli or synthetic peptides derived from domain A were used as
substrates in immunoblotting and ELISA assays. According to the reaction pat-
terns of a collection of anti-p68 autoantibody positive sera three groups of sera
were identified: group I contained antibodies binding to a sequence 20 amino
acids long which presumably represents a discontinuous epitope; group II sera
reacted with a five amino acid motif and group III sera contained both of these
antibody specificities. The 5 amino acid sequence motif was also found on a pro-
tein of a highly prevalent human pathogenic virus. Crossreaction of the p68 au-
toantibody with the 5 amino acid sequence motif in the viral sequence context
could be demonstrated with antibodies affinity purified from domain A contain-
ing fusion proteins. The common epitope recognized by antibodies of autoim-
mune sera suggests that these human viruses may play a role in initiation of
autoimmunity to the well-known p68 antigen. This working hypothesis is current-
ly under investigation.
Human Autoantibodies to Synaptonemal Complex
T. Haaf, A. Machens, and M. Schmid
Department of Human Genetics, University of Wurzburg, Wurzburg, FRG
Autoantibodies to synaptonemal complex (SC) are spontaneously produced
by patients with various autoimmune diseases. The synaptonemal complex forms
the proteinaceous axis between pairing chromosomes during meiotic prophase;