Abstract |
The HLA-DQ beta-chain gene shows a close association with susceptibility or resistance to autoimmune insulin-dependent diabetes mellitus ( IDDM) and it has been suggested that the amino acid in position 57 may be of pathogenetic importance. To study the expression of the IDDM associated HLA-DQ beta-chain alleles, we immunized rabbits with 12 to 13 amino acid long peptides representing HLA-DQw7 and -DQw8 allelic sequences, differing only by one amino acid in position 57 being aspartic acid (Asp) and alanine (Ala), respectively. Immunoblot analysis of lymphoblastoid cells showed that several antisera recognized a 29-kDa protein, equivalent to the expected molecular size of the HLA-DQ beta-chain to yield two antisera specific for HLA-DQw7 (pos. 57Asp) and three antisera for HLA-DQw8 (pos. 57Ala) positive cells. Analysis of HLA-DR 3/4 positive IDDM patients (n = 24) and controls (n = 19) showed that all (100%) patients were positive for pos. 57Ala antiserum compared to 13 of 19 (68%) of the controls. The remaining six controls reacted with the pos. 57Asp antisera, whereas none of the patients did. We have therefore successfully been able to generate site-specific antibodies that distinguish single amino acid substitutions in predetermined positions of allelic HLA-DQ beta-chain gene products. Such sera should become useful to detect and investigate HLA associated susceptibility to autoimmune diseases in man.
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Authors | D Atar, T Dyrberg, B Michelsen, A Karlsen, H Kofod, J Mølvig, A Lernmark |
Journal | Journal of immunology (Baltimore, Md. : 1950)
(J Immunol)
Vol. 143
Issue 2
Pg. 533-8
(Jul 15 1989)
ISSN: 0022-1767 [Print] United States |
PMID | 2738402
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- HLA-DQ Antigens
- Immune Sera
- Peptide Fragments
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Topics |
- Alleles
- Amino Acid Sequence
- Antibody Specificity
- Diabetes Mellitus, Type 1
(diagnosis, genetics, immunology)
- Enzyme-Linked Immunosorbent Assay
- HLA-DQ Antigens
(genetics, immunology)
- Humans
- Immune Sera
- Immunoblotting
- Molecular Sequence Data
- Molecular Weight
- Organ Specificity
- Peptide Fragments
(immunology)
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