To further focus analysis on cell contact-induced changes in producer cells and minimize downstream effects on signaling pathways [34] from cell-free infection, we transfected Jurkat producer cells with a plasmid carrying an HIV-1 provirus [38,72] expressing a GFP—NanoLuc luciferase fusion gene (Promega), and an HIV-1 Env and Nef expression plasmid [40]. This evidence concerns the gene S100B and infection.