| 1. |
- Christie, M., et al.
(författare)
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Antibodies to a Mr-64000 islet cell protein in Swedish children with newly diagnosed Type 1 (insulin-dependent) diabetes
- 1988
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Ingår i: Diabetologia. - 0012-186X. ; 31:8, s. 597-602
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Tidskriftsartikel (refereegranskat)abstract
- Sera from 40 Swedish children diagnosed as having Type 1 (insulin-dependent) diabetes mellitus during a one year period along with 40 age and geographically matched control subjects were tested for antibodies to a Mr-64000 islet protein by immunoprecipitation of 35S-methionine-labelled rat islet amphiphilic proteins. Of the 40 diabetic patients, 29 (73%) were found to be positive whereas all 40 control subjects were negative. Samples were also tested for titres of islet cell cytoplasmic antibodies by indirect immunofluorescence on frozen sections of human pancreas. In the diabetic group, 30 of the 40 patients (75%) were positive for islet cell cytoplasmic antibodies compared with 2 of the 40 control subjects (5%). A comparison of levels of antibodies to the Mr-64000 protein with islet cell cytoplasmic antibodies revealed a weak (rs=0.46), but significant (p<0.01) correlation between the two tests. There was no effect of age or sex on levels of antibodies to the Mr-64000 protein. These results in population-based diabetic children and control subjects demonstrate a high frequency of antibodies to the Mr-64000 protein at the time of clinical onset.
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| 2. |
- Landin-Olsson, M., et al.
(författare)
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Islet cell and other organ-specific autoantibodies in all children developing Type 1 (insulin-dependent) diabetes mellitus in Sweden during one year and in matched control children
- 1989
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Ingår i: Diabetologia. - 0012-186X. ; 32:6, s. 387-395
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Tidskriftsartikel (refereegranskat)abstract
- The majority (about 90%) of children developing Type 1 (insulin-dependent) diabetes mellitus do not have a first-degree relative with the disease. Nearly all (389/405, 96%) children (0-14 years) in Sweden, who developed diabetes during one year, were therefore studied to compare islet cell, thyroid peroxidase, thyroglobulin, and gastric H+, K+-ATPase antibodies with 321 age, sex, and geographically matched, but non-related, control children. Islet cell (cytoplasmic) antibodies were found in 81% (316/389) of the patients and in 3% (9/321) of the control children (p<0.001). The median islet cell antibody levels were 70 (range 3-8200) Juvenile Diabetes Foundation (JDF) Units in the islet cell antibody positive patients, and 27 (range 17-1200) JDF Units in the control children (NS). Autoantibodies against thyroid peroxidase (8%), thyroglobulin (6%), and gastric H+, K+- ATPase (3%) were all increased in the patients compared with the control children, being 2% (p<0.001), 2% (p<0.01), and 0.3% (p<0.01), respectively. During an observation time of 20-34 months, two of the nine islet cell antibody positive control children developed Type 1 diabetes, after 8 and 25 months respectively, while the others remained healthy and became islet cell antibody negative. None of the islet cell antibody negative control children developed diabetes during the same time of observation. This first investigation of an unselected population of diabetic children and matched control children shows: that islet cell antibodies are strongly associated with newly diagnosed childhood diabetes, that other autoantibodies are more frequent among diabetic children than control children, and that the frequency of islet cell antibodies in the background population of children is higher than previously documented, and could also be transient, underlining that factors additional to islet cell antibodies are necessary for the later development of Type 1 diabetes.
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| 3. |
- Madsen, O D, et al.
(författare)
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A two-colour immunofluorescence test with a monoclonal human proinsulin antibody improves the assay for islet cell antibodies
- 1986
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Ingår i: Diabetologia. - : Springer-Verlag New York. - 0012-186X .- 1432-0428. ; 29:2, s. 8-115
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Tidskriftsartikel (refereegranskat)abstract
- The conventional indirect immunofluorescence assay for islet cell antibodies was compared with a two-colour immunofluorescent assay to detect both islet cell antibodies with fluorescein isothiocyanate-labeled rabbit anti-human IgG and pancreatic B cells with a monoclonal human proinsulin antibody and Texas red-labeled sheep anti-mouse IgG. Determinations of end-point titres showed a correlation between the new two-colour immunofluorescent assay and the conventional indirect immunofluorescent assay in 1) selected sera positive for islet cell antibodies and insulin autoantibodies rs = 0.93 (p less than 0.01) or for islet cell antibodies alone rs = 0.99 (p less than 0.005) and 2) sera from children or young adults with newly diagnosed Type 1 (insulin-dependent) diabetes rs = 0.95 (p less than 0.0001). No interference between the monoclonal human proinsulin antibodies and islet cell antibodies with or without insulin autoantibodies or between the two second fluorescent antibodies was detected. It is concluded that the two-colour immunofluorescence assay is advantageous since it is possible to mix the reagents to avoid a more time-consuming and technically complicated assay, the presence of B cells can be confirmed in each section to permit detection of B cell cytoplasmic antibodies and microscopic evaluation is easier and more accurate, particularly in islet cell antibody negative samples.
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| 4. |
- Olsson, M. Landin, et al.
(författare)
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Prolonged incubation in the two-colour immunofluorescence test increases the prevalence and titres of islet cell antibodies in Type 1 (insulin-dependent) diabetes mellitus
- 1987
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Ingår i: Diabetologia. - 0012-186X. ; 30:5, s. 327-332
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Tidskriftsartikel (refereegranskat)abstract
- The conventional indirect immunofluorescence test of islet cell antibodies was recently improved by the development of a two-colour immunofluorescence assay using a monoclonal proinsulin antibody to detect islet B cells. The aim of this study was to test whether in this new assay the prevalence and titre of ICA were affected by the time of incubation carried out in the presence of aprotinin (Trasylol) as an inhibitor of proteolysis. The end-point titre of ICA was therefore determined in sera from 70 children aged 0.6 to 15 years with recent onset Type 1 (insulin-dependent) diabetes mellitus, 50 healthy control subjects and 97 non-diabetic siblings of Type 1 diabetic children. In the conventional twocolour assay, ICA was positive in 53/70 (76%) Type 1 diabetic patients, 1/50 control subjects and 2/97 siblings after 30 min incubation. Prolonged incubation for 18 h increased the prevalence of ICA positive samples to 62/70 (89%) in the diabetic patients and to 2/50 in the control subjects, while the prevalence among the siblings was unchanged. Of the ICA positive non-diabetic subjects, one control child has a father with Type 1 diabetes, and one of the siblings subsequently developed Type 1 diabetes. In the diabetic patients the median titre was 1:32 for the 30 min incubation, and it increased to 1:64 for the 18 h incubation (p<0.001). A marked prozone effect was seen; 16% of the samples from the Type 1 diabetic children sera were negative at a 1:2 dilution, but were found positive at higher dilutions. In conclusion, an 18 h incubation increases the end point titres and the prevalence of ICA in the two-colour ICA assay in Type 1 diabetic children of recent onset. The prevalence and levels of ICA among these patients may be larger than hitherto expected.
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