"Trapping" the AIDS virus

[Mercurial]

For some reason this seems like a lil ridiculous since I thought about it while I was driving but here goes...

 

So the AIDS virus preferentially attacks T-cells and being a retrovirus has RNA that is translated to DNA via reverse transcriptase which in turn is incorporated into the host cell's genome which codes for the viral structure proteins. The fact that it's preferential for the T-cells means that it preferentially binds with a receptor?/glycoprotein?/sugar? that specifically on the outside of the T-cell.

 

And now the question...

 

Can you design a liposome with the receptors the virus recognizes incorporated into the membrane and thus will attack instead of the T-cells. Will the virus still insert its genetic material into the liposome? My thought is that if this happens the liposome having no nucleus, no DNA and no molecular machinery itself will just trap the DNA rendering the virus harmless and the virus will be unable to reproduce.

I realize of course that does nothing to help cells that have already been infected but it might slow down the spread of the infection by rendering some of the viri unable to reproduce. Is there some flaw in this thought. Or are they already trying this? What do yall think?

[zyncod]

It might work, except that you'd have to flood the body with the liposomes constantly - like for the rest of the patient's life. Also, the liposomes wouldn't have access to the lymphatics or lymphatic organs (eg, spleen, lymph nodes) - so infection would continue to occur there. Also, macrophages, monocytes, and dendritic cells love to eat little membrane-bound things, so the half-life of the liposomes wouldn't be very long.

[Dak]

The fact that it's preferential for the T-cells means that it preferentially binds with a receptor?/glycoprotein?/sugar?

 

CD4 is the main cell-surface molecule that is present on helper-t-cells/macrophages that HIV targets.

 

gp120 is the HIV molecule that recognises CD4

 

it has, in actual fact, been tried, although i'm not sure how effective the decoy-liposomes were.

 

Dont forget that after HIV has fused with the decoy liposomes, the decoy liposomes will have gp120 on their surface, and so the liposomes themselves will fuse with CD4+ cells (macrophages, helper-t-cells, or other decoy liposomes), which would complecate the whole matter. non-infected CD4+ cells fusing with CD4+/gp120+ cells to form sinctia (big blobs formed by lots of joined together cells) is a huge contributing factor to the depletion of CD4+ cells.

[Dr. Dalek]

Can you design a liposome with the receptors the virus recognizes incorporated into the membrane and thus will attack instead of the T-cells. Will the virus still insert its genetic material into the liposome? My thought is that if this happens the liposome having no nucleus' date=' no DNA and no molecular machinery itself will just trap the DNA rendering the virus harmless and the virus will be unable to reproduce.

I realize of course that does nothing to help cells that have already been infected but it might slow down the spread of the infection by rendering some of the viri unable to reproduce. Is there some flaw in this thought. Or are they already trying this? What do yall think?[/quote']

 

Aren’t liposome’s absorbed by body cells? If so you would have to fill the liposome with HIV antibodies to prevent them from attacking a cell if the liposome is absorbed or destroyed.

 

CD4 is the main cell-surface molecule that is present on helper-t-cells/macrophages that HIV targets.

 

gp120 is the HIV molecule that recognises CD4

 

it has' date=' in actual fact, been tried, although i'm not sure how effective the decoy-liposomes were.

 

Dont forget that after HIV has fused with the decoy liposomes, the decoy liposomes will have gp120 on their surface, and so the liposomes themselves will fuse with CD4+ cells (macrophages, helper-t-cells, or other decoy liposomes), which would complecate the whole matter. non-infected CD4+ cells fusing with CD4+/gp120+ cells to form sinctia (big blobs formed by lots of joined together cells) is a huge contributing factor to the depletion of CD4+ cells.[/quote']

 

Aren’t some people born without CD4? Like that guy, Steve Crone, a man who supposedly can't get HIV.

[Dak]

i doubt it. some people are born without CCR5, which most strains of HIV use as a co-receptor, thus confuring resistance against most strains of HIV (although some strains use CXCR3 as a co-receptor).

 

i'm not sure what you mean by blocking CD4 forsing HIV to enter the liposome traps -- if you block CD4 you will prevent HIV entry into the CD4+ cells, but also block entry into the CD4+ liposomes.

 

Antibodies that block part of CD4 (thus preventing HIV from recognising it, whilst leaving the molecule able to perform it's normal function) have been developed as a cure/vaccine, but they don't work particularly well.

 

[edit]@ below: ah right [/edit]

[Dr. Dalek]

i'm not sure what you mean by blocking CD4 forsing HIV to enter the liposome traps -- if you block CD4 you will prevent HIV entry into the CD4+ cells, but also block entry into the CD4+ liposomes.

 

I edited that out of my post before I saw your response because I realized it didn't make sense.

[idreesashah]

i was just going through the message posted by some fellow who has sujested using liposomes in traping hiv. i was thinking on this idea for a long time .now at the moment i want to know that how efficient this system can be.?