Posted on 02/17/2005 5:06:16 AM PST by Mother Abigail
Is 3-DCR HIV NYC A Recombinant?
The test results indicate that the virus uses a receptor that has been linked to accelerated immune destruction and rapid progression to clinical AIDS.
Viruses with significant resistance often replicate less well than wild-type viruses. In this case however, the ViroLogic Replication Capacity (RC) assay indicated that virus replication was comparable to most wild-type strains.
Replication Capacity is the focus of intensive study at ViroLogic and preliminary data indicate that viruses with high RC values are associated with more rapid immunosuppression.
This is an interesting case because it has features that we often see, although not typically in the same virus. While we see triple-class resistance fairly commonly in patients with a long history of antiretroviral drug experience, this case is noteworthy in that a single virus harbors triple-class resistance, a high RC, and CXCR4 receptor tropism in the setting of recent infection.
The 3-DCR profile along with a wild type replication capacity is further reason for obtaining a full sequence.
Analysis will reveal if the virus in question is a recombinant, combining two well characterized biological properties to generate a novel virus with increased virulence and transmissibility, combined with drug resistance.
The presence of this unique set of properties in a single virus should speed up analysis of the significance of the NYC cluster.
The key assays are commercially available, so screening of suspect virus should allow rapid determination of the worldwide distribution of this novel strain.
Tracing will help define how successful containment might be, and also identify treatment options, although treating with one drug is unlikely to provide a long term solution.
The identification of a second case in San Diego is not a good indicator, unless there is some linkage between the patient in California and one or both patients in NYC. However, since initial comments indicated the viruses were similar, as opposed to almost identical, the chance that this virus is spreading well beyond the three cases being investigated is high.
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Increased Replication Capacity of 3-DCR HIV
Assays have already been run on the 3-DCR HIV NYC to test for virulence. The isolate was CXCR4 tropic, consistent with resistance to 19 of the 20 FDA approved HIV antivirals.
However, it had a wild type Replication Capacity which was unusual for a CXCR4 tropic isolate. Since these assays are done in vitro, they would be independent of host factors.
Complete sequencing and structural analysis could shed additional light on the mechanism used to merge these two properties, but the data already shows that the virus has combined two properties that would be expected if the virus was more virulent.
The effect of these genetic changes on disease progression in a large population remains to be determined. However, the data on combining properties which are consistent with increased virulence have already been described.
2. The above details clearly point toward a novel HIV rather than an immuno-compromised host in the DCR NYC case cluster.
FYI
By recombinant, does that imply "design" in a laboratory?
No laboratory is required.
Interesting... Thanks...
ping (!)
As the article states, the likelihood that it has spread far beyond the cases we know of today is high.
Culling the herd. Rapidly.
Recombinant HIV with increased lethality and speed in which it destroys the immune system must have a host that has receptors available to the virus. I believe that we will see a human genome characteristic that will predict the outcome of the Super HIV strain in infected individuals. The mere fact the patient has the recombinant strain expressed as a disease is de facto evidence that the receptor is present. If viral history is to repeat itself, we will also see a carrier of the super strain that will infect but not show clinical disease.
My bet is there is a carrier that has the 3-DCR HIV NYC and is not exhibiting clinical disease. I would look for an angry French Canadian connected with the airline industry that has homosexual sex with multiple individuals.
That could be any of them.
http://www.freerepublic.com/focus/f-news/1315719/posts
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11877445&dopt=Abstract (that' a freebee)
Hmm, could this be man-made?
Go to the Drudge Report, there is a carrier that has had sex with over a hundred men. The possibility was too real to not think there was a carrier.
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