Method of detecting protein by immuno RNA

A method of detecting a phosphorylated tau protein by immuno-aRNA, wherein the presence of the phosphorylated tau protein is correlated with Alzheimer's disease comprising:

• a) immobilizing a first antibody targeted to a phosphorylated tau protein to a solid support;
• b) contacting the solid support with the protein so that the phosphorylated tau protein binds to the immobilized first antibody;
• c) contacting the solid support with a RNA promoter-driven cDNA sequence covalently coupled to a second antibody targeted to the phosphorylated tau protein so that the second antibody binds to the bound phosphorylated tau protein on the solid support;
• and
• d) detecting the promoter-driven cDNA sequence covalently coupled to the bound second antibody by amplified RNA techniques, wherein the presence of the promoter-driven cDNA is indicative of the presence of the phosphorylated tau protein in the cell, said protein correlating with Alzheimer's disease.