Site-specific antibodies distinguish single amino acid substitutions in position 57 in HLA-DQ beta-chain alleles associated with insulin-dependent diabetes
Research output: Contribution to journal › Journal article › Research › peer-review
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.
Original language | English |
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Journal | Journal of Immunology |
Volume | 143 |
Issue number | 2 |
Pages (from-to) | 533-8 |
Number of pages | 6 |
ISSN | 0022-1767 |
Publication status | Published - 15 Jul 1989 |
- Alleles, Amino Acid Sequence, Antibody Specificity, Diabetes Mellitus, Type 1, Enzyme-Linked Immunosorbent Assay, HLA-DQ Antigens, Humans, Immune Sera, Immunoblotting, Molecular Sequence Data, Molecular Weight, Organ Specificity, Peptide Fragments
Research areas
ID: 45574977