Abstract: A kit for evaluating residual host deoxyribonucleic acid (DNA) in a cellular formulation includes substances, a primer pair, a probe, a reference vector and an instruction. The substances are used for quantifying the amount of the host DNA. The primer pair is used for Polymerase Chain Reaction (PCR) amplifying a plasmid Ori element and/or a KanR gene. The plasmid Ori element has a nucleic acid sequence of SEQ ID NO: 1, and the KanR gene has a nucleic acid sequence selected from a group consisting of SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 4, and SEQ ID NO: 5. The probe is used for detecting a plasmid Ori element and/or a KanR gene. The reference vector used as a standard includes the plasmid Ori element and/or the KanR gene. The instruction indicates the procedures for evaluating the residual host DNA.

Abstract: The present application relates to the field of biotechnology, particularly to a plasmid target, a primer probe, a kit and a method for detecting residual host DNA in a cellular or viral formulation. The plasmid target is one or two selected from a plasmid Ori and a KanR gene, the Ori element has a gene sequence of SEQ ID NO. 1, and the KanR gene has a gene sequence capable of encoding a Kan R peptide chain, wherein the Kan R has amino acid sequences of SEQ ID NOs. 2-5. The present application also relates to a primer probe for the plasmid target, a kit, and a applying method.