Compositions, methods and kits for detection of an antigen on a cell and in a biological mixture

A method of detecting the presence of a plurality of known antigen-bearing moieties on a cell in a single tube assay, said method comprising the steps of:

• 1) antigen detection, 2) amplification of phage nucleic acid, and 3) detection of phage nucleic acid,
• wherein said antigen detection step consists of:
• contacting a cell with a plurality of bacteriophage types, each expressing an antibody known to specifically bind with an antigen-bearing moiety wherein each of said bacteriophage type comprises a nucleic acid comprising a nucleic acid sequence that encodes the antibody, wherein the sequence that encodes the antibody is known and at least a portion of the sequence is correlated to the phenotype of one of said plurality of known antigen-bearing moieties, wherein the sequence that encodes the antibody from each of said bacteriophage type is detectably different from the sequence that encodes the antibody from all other bacteriophage types;
• wherein said amplification step comprises conducting PCR reactions using nucleic acid primers that anneal to said nucleic acids in each of said bacteriophage types to generate amplified products, wherein the amplified products comprise at least a portion of the sequence that encodes the antibody;
• and
• wherein said detection of phage nucleic acid step consists of detecting the binding of each of said bacteriophage type with each of said antigen-bearing moiety by detecting the presence of each of said amplified product using a melting curve profile, wherein detecting each of said amplified product detects the presence and phenotype of each of said antigen-bearing moiety on said cell.