Antibodies for use in determining hemoglobin A.sub.1c

DETAILED DESCRIPTION It is accordingly an object of the present invention to provide a comparatively simple, inexpensive, reliable test for determining the long-term blood sugar level of a patient based on the immunoassay determination of Hb A.
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lc.
It is another object of the invention to provide such a test for determining the content of glucosylated hemoglobin, Hb A.
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1c, in a patient's whole blood sample.
These and other objects and advantages are realized in accordance with the present invention pursuant to which there are provided monoclonal antibodies, or fragments thereof comprising an antibody binding site, which will selectively react with the glucosylated peptide N-terminal residue in Hb A.
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lc, but not with nonglucosylated forms of such protein so that the extent of reaction is a measure of the N-terminal glucosylated content which, in turn, is a measure or index of the diabetic condition.
It is a further object of the invention to provide cell lines which will readily produce such monoclonal antibodies having desired specificity for glucosylated peptide residues, specifically the residue found in Hb A.
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lc.
The present invention now provides the means for a highly specific immunoassay determination of glucosylated hemoglobin in biological fluids such as whole blood.
Monoclonal antibodies raised against the synthetic glucosylated N-terminal peptide residues appearing in Hb A.
sub.
lc have been found to bind specifically to such residues in the glucosylated beta-subunit of hemoglobin.
The antibodies can be prepared in a variety of manners following conventional antiserum and monoclonal techniques.
Principally, the antibodies are prepared against a synthetically derived immunogen comprising the desired glucosylated N-terminal peptide residue chemically linked to an immunogenic carrier, the glucosylated peptide having at least 2, and preferably from about 5 to 15, amino acid units corresponding to Hb A.
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lc.
The resultant monoclonal antibodies are specific for the glucosylated synthetic peptide and the corresponding exposed epitope for the hemoglobin A