ELISAS FOR ISLET CELL AUTOIMMUNITY AND PREDIABETES

STRONG EVIDENCE HAS ACCUMULATED TO SUGGEST THAT INSULIN-DEPENDENT DIABETES IS THE RESULT OF AUTOANTIBODIES AGAINST INSULIN AND/OR SUBCELLULAR COMPONENTS OF THE CELLS OF THE ISLET OF LANGERHANS. DETECTION OF THESE AUTOANTIBODIES WILL GIVE PRIOR KNOWLEDGE OF THE DISEASE IN ORDER THAT PREVENTIVE MEASURES CAN BE TAKEN TO AVERT OR DELAY THE DISEASE. IN PHASE FRACTIONS FROM PURCHASED SEMI-SYNTHETIC HUMAN INSULIN, ISLET CELLS FROM PORCINE, BOVINE AND HUMAN SOURCES WILL BE ISOLATED, VIZ., PLASMA MEMBRANE ENRICHED FRACTION, MIXED SECRETORY GRANULES, MITOCHONDRIA AND THE ENDOPLASMIC RETICULUM ENRICHED FRACTION. THE SAME SUBCELLULA FRACTIONS WILL BE ISOLATED FROM INSULINOMA CELL LINES. PURE INSULIN AND EACH FRACTION FROM EACH SOURCE WILL BE BOUND TO SOLID PHASE MATRICES. PRECHARACTERIZED, STANDARD SERA CONTAINING ANTI-ISLET AUTOANTIBODIES FROM DIABETIC PATIENTS WILL BE INCUBATED TOGETHER WITH MATRIX-BOUND FRACTIONS TO REACT WITH SPECIFIC COMPONENT (S). ENZYME-BOUND ANTI-HUMAN IGG WILL BE ADDED TO DETECT ANTIGEN-BOUND ANTIBODIES. THIS PROCEDURE WILL DETERMINE THE FRACTIONS CONTAINING THE SPECIFIC ANTIGENS AGAINST WHICH AUTOANTIBODIES ARE DIRECTED AND ESTABLISH THE FEASIBILITY OF ELISA FOR THE QUANTIFICATION OF ANTI-INSULIN AND ANTI-ISLET CELL ANTIBODIES. ABSOLUTE SPECIFICITY CAN BE ASSURED BY PURIFICATION OF THE ISLET CELLGLYCOPROTEINS AND GLYCOLIPIDS TO HOMOGENEITY BY AFFINITY CHROMATOGRAPHY. IN PHASE II, MONOCLONAL ANTIBODIES AGAINST THESE SPECIFIC AND REACTIVE (WITH HUMAN DIABETES SERUM) FRACTIONS WILL BE PREPARED. THESE ANTIBODIES WILL BE USED FOR AFFINITY PURIFICATION OF LARGE AMOUNTS OF THESE ANTIGENS TO BE USED FOR FURTHER DEVELOPMENT OF BOTH A RAPID, DIPSTICK SCREENING TEST AND AN ACCURATE QUANTITATIVE ELISA TEST FOR CLINICAL TRIALS