Abstracts
41
Ankylosing Spondylitis (AS) and Rheumatoid Arthritis (RA):
Improved Diagnosis and Attempts Towards the Molecular Analysis of
Etiology and Pathogenesis of These Systemic Rheumatic Diseases
H.-J. Lakomek1, and M. Schwochau2
1 Medizinische Klinik und Poliklinik, Heinrich-Heine-Universitat Dusseldorf,
4000 Dusseldorf 1, FRG
2Institut fur Genetik, Heinrich-Heine-Universitat Dusseldorf, 4000 Dusseldorf 1, FRG
Low concitivity of the commonly applied clinical criteria render the diagnosis
of rheumatic diseases in general rather difficult, particularly in the early stages
of these disorders. The identification of serological parameters specific for a par-
ticular disease would allow an earlier diagnosis with higher diagnostic confidence
and open the way for a molecular analysis of the underlying pathomechanisms.
Investigating a set of xenotypic and homotypic antigen pools by immunoblot-
ting techniques we were able to identify autoantibodies specific for AS and RA
respectively.
Total protein preparations of insect tissues (Kc0 cells of Drosophila
melanogaster) contain at least four different antigens (36, 45, 52, and 74 k) reac-
ting with antibodies present in sera of AS patients. The sera of these patients con-
tain additional antibodies reacting specifically with the 93 D heat shock puff of
D. mel. polytene chromosome preparations. Employing cytoimmunofluorescence
and immunoblotting techniques AS associated antibodies were found in 82To of
all AS patients and patients with suspected AS.
Concentrating on the most prominent reaction we further characterized and
purified the 36 k antigen in order to isolate the respective antibody, which in turn
is used to identify the corresponding human antigens.
Total protein preparations of human tissues (synovia, lymphocytes, and HeLa
S3 cells) contain a 68 k antigen reacting with antibodies present in the sera of 64To
(n = 84) of RA patients (diagnosed according to the ARA criterial). None of the
sera of apparently healthy (n = 55) and only 6To of the sera of other arthrophaties
(n = 82) (AS, reactive arthritis, SLE, PSS, overlap SLE/PSS, morphea, and OA)
contained this antibody.
The 68 k antigen detected by the RA specific antibodies was further character-
ized (IEP: 5.1), purified and isolated, rendering the application of an ELISA tech-
nique for a specific and quantitative estimation of this antibody feasable.
The antibody against the 68 k antigen can readily be eluted from immunoblots
thus opening the way to immunoscreening of the gene coding for the 68 k antigen
from an appropriate cDNA expression library.
41
Ankylosing Spondylitis (AS) and Rheumatoid Arthritis (RA):
Improved Diagnosis and Attempts Towards the Molecular Analysis of
Etiology and Pathogenesis of These Systemic Rheumatic Diseases
H.-J. Lakomek1, and M. Schwochau2
1 Medizinische Klinik und Poliklinik, Heinrich-Heine-Universitat Dusseldorf,
4000 Dusseldorf 1, FRG
2Institut fur Genetik, Heinrich-Heine-Universitat Dusseldorf, 4000 Dusseldorf 1, FRG
Low concitivity of the commonly applied clinical criteria render the diagnosis
of rheumatic diseases in general rather difficult, particularly in the early stages
of these disorders. The identification of serological parameters specific for a par-
ticular disease would allow an earlier diagnosis with higher diagnostic confidence
and open the way for a molecular analysis of the underlying pathomechanisms.
Investigating a set of xenotypic and homotypic antigen pools by immunoblot-
ting techniques we were able to identify autoantibodies specific for AS and RA
respectively.
Total protein preparations of insect tissues (Kc0 cells of Drosophila
melanogaster) contain at least four different antigens (36, 45, 52, and 74 k) reac-
ting with antibodies present in sera of AS patients. The sera of these patients con-
tain additional antibodies reacting specifically with the 93 D heat shock puff of
D. mel. polytene chromosome preparations. Employing cytoimmunofluorescence
and immunoblotting techniques AS associated antibodies were found in 82To of
all AS patients and patients with suspected AS.
Concentrating on the most prominent reaction we further characterized and
purified the 36 k antigen in order to isolate the respective antibody, which in turn
is used to identify the corresponding human antigens.
Total protein preparations of human tissues (synovia, lymphocytes, and HeLa
S3 cells) contain a 68 k antigen reacting with antibodies present in the sera of 64To
(n = 84) of RA patients (diagnosed according to the ARA criterial). None of the
sera of apparently healthy (n = 55) and only 6To of the sera of other arthrophaties
(n = 82) (AS, reactive arthritis, SLE, PSS, overlap SLE/PSS, morphea, and OA)
contained this antibody.
The 68 k antigen detected by the RA specific antibodies was further character-
ized (IEP: 5.1), purified and isolated, rendering the application of an ELISA tech-
nique for a specific and quantitative estimation of this antibody feasable.
The antibody against the 68 k antigen can readily be eluted from immunoblots
thus opening the way to immunoscreening of the gene coding for the 68 k antigen
from an appropriate cDNA expression library.