Hiv-1 contains cd9 and cd63

Although CD9 and CD63 are used to detect extracellular vesicles, they are also present in viruses that use outward budding from host cell membrane to form their envelope[@duijvesz2015aImmuno-based detection of extracellular vesicles in urine as diagnostic marker for prostate cancer: Extracellular vesicles as marker for PCa]. Such is the case of the HIV-1 virus.

During the infection, there can be a change in the small EV composition[@martinjaular2021Unbiased proteomic profiling of host cell extracellular vesicle composition and dynamics upon HIV-1 infection], but the most important challenge is that the nascent viral particle is similar to EV composition, size, and physical features. Therefore it is challenging to distinguish HIV viruses from EVs.

One path forward could be to perform a proteomeic profile of EVs in order to study difference at a protein level.