**3. Semen exosomes in HIV-1 patient**

HIV-1 could transmit via the semen through sexual intercourse and is the leading cause of HIV-1 transmission worldwide during vaginal and rectal intercourse by human beings. The major route of transmission is the vaginal secretion during the sexual intercourse to the person who is involved in this period [44]. Exosomes play an important role in intracellular communication. Semen exosomes are epididymosomes and prostasomes. Epididymosomes and prostasomes are exosomes involved in the acquisition of fertilising ability, modulation of motility, maturation of spermatozoa and could be a possible biomarker in the early diagnosis of male infertility [45].

The identified proteins in the blood exosome and semen exosome are useful as a biomarker applicable to different fields of medicine, especially in reproduction and infectious diseases. The proteomic profiling of semen exosomes and blood exosomes from HIV-infected and uninfected individuals was compared. The compositional and functional variabilities were observed. Semen exosomes were enriched in clusterin protein compared with the blood exosome in HIV-infected and uninfected patients [46]. The antiretroviral activity of the human semen exosome was reported. The human semen exosome inhibits the HIV-1 replication, and it could be useful as a therapeutic purpose for HIV-1. Semen exosomes restrict HIV-1 transmission by vaginal cells. This study of the semen exosomes helps the development of the therapeutic diagnosis during the transmission of HIV-1 [13]. Semen and vaginal fluid exosomes of healthy individuals could inhibit the HIV-1 infection and block the transfer of HIV-1 into vaginal cells [47]. *In vitro* and *in vivo* study of HIV-1 infected, uninfected patients, ART naïve, ART patients' semen exosome were isolated and found the inhibition of replication of HIV-1 [48]. The semen exosomes in HIV-1 patients could be an option for the development of novel therapeutic biomarkers in the field of infertility and the diagnosis of AIDS.
