High-Throughput Antigen Screening via an Invariant Chain Fusion Protein & the MHC Class II Receptor

The human body’s immune system utilizes many different cell types, signaling proteins, and receptors to thwart an infectious pathogen from an individual. Adaptive immunity, particularly with CD4+ T cell lymphocytes & the MHC II receptor, was the focus of this paper by creating a custom destination vector plasmid, pFLIiP, which would contain a gateway cloning site and the nucleotides encoding the first 85 amino acids of the invariant chain protein upstream to provide a means of high-throughput antigen screening via the MHC II receptor and peptide processing pathway. The plasmid pFLIiP was successfully created and sequence verified. Both GFP and mCherry fluorescent proteins were inserted into pFLIiP via LR Clonase and successfully transfected into K562 cancer cells. Fluorescent activity read of a flow cytometer in conjunction with the differing pKa values of the two different fluorescent proteins suggested the fusion protein was in-frame and pFLIiP was successfully targeting the protein to the endosome.