Ultrasensitive detection of mucin 1 biomarker by immuno-loop-mediated isothermal amplification.

Mucin 1 (MUC-1), a glycoprotein over-expressed on most malignant epithelial cell surfaces, such as colorectal, lung, prostate, pancreatic, ovarian, and bladder carcinomas, has been confirmed as a useful biomarker for the diagnosis of early cancers. Therefore, it is very important for early cancer diagnoses to develop the sensitive and specific detection approach of MUC-1. In this paper, we report a novel technique of aptamer-based Immuno-Loop-Mediated Isothermal Amplification (Im-LAMP) for the quantitative detection of MUC-1 by MUC-1 aptamer with high affinity for MUC-1. The cycle time is linearly dependent on the logarithm (log) of the concentration of mucin 1 ranging from 1.0 pM to 1.0 aM. We call this technique Im-LAMP, which is a novel method for the detection of low-abundance proteins with high sensitivity (a low detection limit of 120 MUC-1 molecules by calculation)and specificity. Finally, this approach is also successfully applied in the analysis of human blood serum samples. It also lays the foundation for the early diagnosis of different types of low-abundance cancer biomarkers.