Horse radish peroxidase (HRP) is treated with phenyl isothiocyanate (PITC) to block the free amino groups on the enzyme. The PITC derivative of HRP is treated with periodate to oxidize the carbohydrate moiety on the enzyme, thus generating aldehyde groups. Gamma G globulin fraction (IgG) purified from an anti-human IgE serum is conjugated to the peroxidase-aldehyde by formation of a Schiff's base between the aldehyde group on the enzyme and the amino groups on the IgG. The Schiff's base is stabilized by reduction using the optimal amounts of sodium borohydride determined by tiration. A stable HRP-anti IgE IgG conjugate prepared thus is employed in a solid phase enzyme immunoassay for the detection of allergen specific IgE. The results of this assay can be used to determine a safe initial hypersensitization dosage level.
The present invention is directed to novel polypeptides and to nucleic acid molecules encoding those polypeptides. Also provided herein are vectors and host cells comprising those nucleic acid sequences, chimeric polypeptide molecules comprising the polypeptides of the present invention fused to heterologous polypeptide sequences, antibodies which bind to the polypeptides of the present invention and to methods for producing the polypeptides of the present invention.
Immunoenzymatic conjugate consisting of glycosylated labelling enzymes in copolymer form and substances having immunological activity. Method for the production of the conjugates according to the invention and use of the said conjugates in diagnostic kits.
Amine-enriched proteins, having an increased isoelectric point are provided by reacting a naturally occurring protein with an amide bond forming agent in the presence of a polyamine or a salt thereof. Such amine-enriched proteins such as enzymes are useful as labels in immunoassays.
A water-soluble cross-linked polymer of the enzyme lysyl endopeptidase produced by Achromobacter lyticus and a process for preparing the polymer as well as a semi-synthesis of human insulin using the polymer.
A method is described for the covalent attachment of linker groups to specific sites on antibody molecules directed against any desired target antigen (tumor, bacterial, fungal, viral, parasitic etc.). These linkers can be attached via amide or ester bonds to compounds for delivery which contain available amino or hydroxy groups (e.g., bioactive agents, cytotoxic agents, dyes, fluors, radioactive compounds, etc.). In addition the linkers can be incorporated into insoluble matrices for use in separation schemes which are based upon antibody-antigen interactions. The linkers may be designed so that they are susceptible to cleavage by any one of the serum complement enzymes. When prepared according to the methods described herein, the resulting modified antibody molecule retains the ability to bind antigen and to fix serum complement. Thus, when administered to a patient the antibody conjugate binds to its target in vivo. As a result of the subsequent activation of the patient's serum complement, the covalently attached compound will be specifically cleaved at the target site by the proteolytic enzymes of the complement system.
