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I was wondering can multiple HIV virus infecting same T cell ? Coz in flu virus they have SA to cleave of those sialic acid residue preventing re-infection of the same cell by other viruses to maximize the amount of cell get infected. I was wondering is there any mechanism found in HIV virus like what found in flu virus to prevent re-infection of an already HIV-infected T cell.

(little bit more about HIV virus that is irrelevant to the question, coz i was told that there is some HIV possible to hide in our body, but then i don't understand what it is the meaning of this hiding? Q1:Is the "hiding" refer to the genome of HIV that integrated into T cell. some of these infected T cells circulating in the blood Q2: will some of them reside in lymph node? Q3: and what make these infected B cell proliferate so to keep these B cell with the hiv genome long existing? will the virus transform these T cells into self proliferating? but will that be like cancer cell uncontrollably proliferating or well controlled?)

Thank you everybody

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  • $\begingroup$ HIV doesn't infect B-cell as far as I remember $\endgroup$
    – WYSIWYG
    Aug 22, 2014 at 14:47
  • $\begingroup$ Oops~ hahahah really thanks for reminding me of that.Omg so embarrassing. Thank you $\endgroup$
    – patpat
    Aug 22, 2014 at 14:50

1 Answer 1

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Yes, HIV does attempt to prevent multiple infection of the same cell. Once a T cell or other cells are infected, HIV downregulates the CD4 receptor which it uses to gain entry. Because of this, there are less receptors so another HIV is less likely to infect that cell. Meanwhile, the infection itself upregulates CD4 receptors on other cells which means the downregulation is even more effective. There are other mechanisms but this is a major one.

Hiding means it is somewhere where we don't know where it is and it isn't that active. When HIV is active it is destructive but also the cell is aware it is there. The cell can then try to alert other cells that it is infected. If HIV isn't active but instead hiding, it can stay where it is without really being detected. Even the drugs we use usually only affect HIV whilst it is replicating. So again if it's in a cell that's long lasting and the HIV is not replicating then it is essentially hiding. Such a cell includes macrophages and memory cells when we are just talking about the immune system.

Will HIV reside in the lymph node? Well yes, this is an exciting place for it. There's loads of exposed CD4 receptors and lot's of it's favourite T cells about. An infected cell will transmit HIV to other cells when they are signalling to each other. Even worse is when a dendritic cell is infected. Instead of instructing the immune system how to detect HIV infected cells, it is infecting them.

HIV is an infection. As soon as the body detects it, it goes into overdrive trying to eradicate it. This means there are more cells for HIV to infect. More foreign material means the immune system is even further stimulated to make even more cells. However it doesn't want CD8 cells to proliferate too much nor too many HIV specific cells so driving too much proliferation is a bad idea. What HIV does do is make lots and lots of useless copies of itself. HIV particles that are so badly made they aren't functional. The body tries to fight these and makes more cells to combat these but there's no point because they aren't the problem. But this immune diversion and a larger target number of cells is exactly what HIV wants. Proliferation of HIV specific cells, particular CD8, is associated with delayed disease progression or control.

Usually the cancers caused by HIV are because of other viruses running unchecked. Kaposi's sarcoma or lymphomas for example.

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  • $\begingroup$ Though at the same time, i have some questions coming up in my mind. The first one is i was wondering is that T cell the only cell get affected by HIV coz macrophages and dendritic cell are mentioned in the answer. mmmm...i wonder how can the HIV get into these non-T cell by skipping the part that they requires CD4 for entry or actually CD4 is also present in these cell besides T cell as well?? 2nd one is what makes HIV prefer to infect memory cell? $\endgroup$
    – patpat
    Aug 25, 2014 at 5:51
  • $\begingroup$ 3rd one is about the upregulation of CD4 cell in other yet infected T cell, is there anything to do with the HIV itself, like the hiv bears some genes to selectively upregulate the CD4 receptor on other unifected T cell or it is the feedback system of the immune system while the HIV has no direct role in the upregulation of CD4? $\endgroup$
    – patpat
    Aug 25, 2014 at 5:55
  • $\begingroup$ The last question is that really bother me is that cant we activate those provirus and force them into actively proliferating form. Then, large dose of antiviral drug are introduced to the system to prevent the newly produced HIV from infecting those uninfected target cell as to completely eradicate the provirus in our cell. I was wondering is it possible.Oh before that, have the mechanism of those pro-HIV been found out yet? $\endgroup$
    – patpat
    Aug 25, 2014 at 5:58
  • $\begingroup$ OH this one is really the last one. I was wondering what is the route for HIV to get into macrophage and other non T cell cell, by recognizing CD4 receptor or other protein? $\endgroup$
    – patpat
    Aug 25, 2014 at 6:24
  • $\begingroup$ Make another question. There's so much to write to answer all those. Add a comment here linking me to them and I'll try to answer $\endgroup$ Aug 25, 2014 at 10:00

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