HCV, HIV, HBV and the effectiveness of PIs

[Andiamo1]

I just went to Mt Sinai for my post 2 week physical and blood draw.  I asked the doctors a lot of questions about these viruses and the effectiveness of PIs in treating them.  There has been a lot of confusion on these boards in some recent threads and I include myself among the confused.

So, from the horses mouth:

HCV and HIV are RNA retroviruses.
HBV is a DNA virus.
However, HBV and HIV only reproduce within cells.  HIV uses the DNA of the host cell to reproduce.
HCV reproduces free in the bloodstream and not within a cell.

This makes HCV much easier to treat with PIs since the virus is exposed during reproduction and the other two are hidden.  This is the reason it is possible to cure HCV with a PI, but HIV and HBV are not curable with PIs.

The current PIs attack the Ns3 protease within the RNA and since they are very selective, the can't inhibit reproduction of all mutations of the virus; thus, SOC is required along with the PI.  The newer PIs in early stages, attack a broader range and the polymerase inhibitors take an entirely different approach.  All the Capo Grandes I spoke with think that in the next few years a cure will be available that no longer requires SOC - thank God!!

Eric

[Andiamo1]

I suggest you give a presentation to the research scientists at Mt Sinai.  They might be enlightened by your explanation.

I did my best to try and find out more about this by talking to experts in the field.  Perhaps they are wrong, I have no way of knowing.  What is your source of information?


Eric

[Andiamo1]

You are most welcome.  It was your comments that prompted me to ask the docs.

[debster39]

What are PIs?

[Andiamo1]

Sorry for the abbreviation - stands for Protease Inhibitors.  A class of designer drugs that attack a specific virus at specific points in the RNA structure and inhibit an enzyme that is required for replication.

I am sure someone will disagree with me on that, so keep reading for clarification or confusion as the case may be. :)

[willing]

the "retro" in retrovirus comes from reverse trascriptase, an enzyme that reverse the normal (dna->rna)direction of transcription into rna->dna .
See for example
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/R/Retroviruses.html

I believe  correct statements are
HCV and HIV are RNA viruses (carry their genome as RNA)

HVB is a DNA virus
(see eg http://www.microbiologybytes.com/virology/HBV.html_

HIV is a retrovirus (generates a DNA intermediate), HCV however is not: DNA never plays a part in the HCV lifecycle

Also, *all* viruses can repoduce only in living cells (that's what makes them a virus), Viruses travel light, only enough baggage to get into a cell and co-opt the cellular machinery to their own reproductive ends; they can't reproduce on their own.  Perhaps the Drs were referring to reproduction in PBMCs, a type of blood cell.

But these are all just details, thanks for checking.

[Andiamo1]

None of us are trained research scientists here especially me.  I am as persistent as a bulldog though and I pester everyone that I think does know something about HCV.

I think that posters on this board should keep an open mind and try to verify their beliefs before they post strong statements.  I am as guilty as anyone of making blanket statements about biochemistry when if fact I am fairly ignorant about this whole field.

Just now I did a google search and found at least 50 sites that claim HCV is a retrovirus, so I think I was given good data.  Might be more than 100 sites :).