Furthermore, in more recent studies investigating pathogenic mechanisms of HIV infection in the brain exacerbated by meth, syncytia formation and subsequent HIV infection was observed through the increasing of intercellular adhesion molecule-1 (ICAM-1) and HIV-Nef protein on extracellular vesicles released from both uninfected and chronically HIV-1 infected promonocytic U1 cells in response to meth (Chand et al., 2022). This evidence concerns the gene ICAM1 and HIV infectious disease.