Just a thought…
The article above in Popular Science is very interesting to me because I wonder whether reverse phage therapy or bacteria therapy would work in HIV. In phage therapy, viruses that kill bacteria are used to kill infectious drug resistant bacteria. If we could use bacteria instead to invite infectious viruses and then clear the bacteria post infection, we can in turn clear the viruses.
In case of HIV, initially I had thought that we could possibly engineer a bacteria to express receptors such as CCR5 or CXCR4 that would lure HIV to infect them instead of CD4+ T cells. These bacteria would also express receptors that would facilitate the opsonization process (clearing of pathogens by immune cells).
However, there major obstacles in this process. First, the interaction of CD4 with other molecules expressed by our cells can prove to be a major obstacle. Next, the bacteria may generate immune response and may be cleared too soon before it can actually circulate in the body. Third, it may cause immune activation which is not necessarily advantageous to a patient. Fourth, how will these bacteria be administered? Fifth, depending the route of administration, they may not clear HIV from hard to reach areas such as gut and brain. Finally and possibly the most importantly, it will not clear latent infections. One more: there will still be CD4+ cells that will be infected…how are we going to deal with them?
Although these questions persist and not being able to answer any one of these questions may render the whole process uneffective, it is important to think about phages in HIV. Despite the fact that there are thousands of papers on HIV and hundreds on phages, to my knowledge, there is not a single scientific literature that has investigated the possible role of the phages in HIV infection/pathogenesis. Therefore, despite various challenges, investigating the the beneficial use of phages in HIV could lead us to a novel way of tackling the HIV epidemic.