HCV difference in life cycle?

[Andiamo1]

Does anyone know why it is possible to cure HCV, but not HIV?  It was explained to me as a difference in the virus life cycle, but the explanation given me had some misconceptions that I would like to clarify.

[lalapple]

HIV can be inhibited as long as long as patients are put on a certain drug (forgot the name i learned in bio).  the drug can even reduce the virus to UND for HIV, however, once the patient is off the drug, HIV returns bc my professor said it can hide during tx.  

i asked my hepa about relapsed for HCV after tx, and she told me that relapse happens when people are reinfected.  didn't mention anything about virus return from hiding in the body.

[CoWriter]

"Also I think HIV passes the brain/blood barrier, which HCV in most cases does not."
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HCV RNA negative strand, which shows replication, was found in the brain tissue of 3 out of 12 Hep C patients in this study.

According to the prevailing hypothesis, circulating lymphocytes cross the blood-brain barrier carrying HCV to the central nervous system ...and the virus is then replicated in the macrophages and microglia in the brain as a separate compartment.
  


HEPATITIS C VIRUS NEUROINVASION: IDENTIFICATION OF INFECTED CELLS.

Wilkinson J, Radkowski M, Laskus T.
St. Joseph's Hospital and Medical Center, Phoenix, Arizona; Institute of Infectious Diseases, Warsaw Medical University, Warsaw, Poland.

Hepatitis C virus (HCV) infection is often associated with cognitive dysfunction and depression. HCV sequences and replicative forms were detected in autopsy brain tissue and cerebrospinal fluid from infected patients suggesting direct neuroinvasion. However, the phenotype of cells harboring HCV in brain remains unclear. We studied autopsy brain tissue from 12 HCV-infected patients, 6 of these patients were coinfected with HIV. Cryostat sections of frontal cortex and subcortical white matter were stained with monoclonal antibodies specific for microglia/macrophages (CD68), oligodendrocytes (CNPase), astrocytes (GFAP) and neurons (NeuN), separated by laser capture microscopy (LCM) and tested for the presence of positive and negative strand HCV RNA. Sections were also stained with antibodies to viral nonstructural protein 3 (NS3), separated by LCM and phenotyped by real-time PCR. Finally, sections were also double stained with antibodies specific for cell phenotype and HCV NS3. HCV RNA was detected in CD68-positive cells in 8 patients and negative strand HCV RNA, which is a viral replicative form, was found in 3 of these patients. HCV RNA was also found in astrocytes from 3 patients, but negative strand RNA was not detected in these cells. In double immunostaining, 83%-95% of cells positive for HCV NS3 were also CD68-positive, while 4% to 29% were GFAP-positive. NS3-positive cells were negative for neuron and oligodendrocyte phenotypic markers. In conclusion, HCV infects brain microglia/macrophages and to a lesser extent astrocytes. Our findings could explain the biological basis of neurocognitive abnormalities in HCV infection.

http://www.ncbi.nlm.nih.gov/pubmed/19019968?ordinalpos=8&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel


Co
P.S.  Things that cause deterioration of the blood-brain barrier and might make it easier for HCV to cross it......high blood pressure, microwaves and HIV.  But I can't remember where I read that.  

[CoWriter]

"With all due respect.... we may have to re-define what we mean when we call people "non-responders".  "
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Nowhere in my posts did I say, "non-responders".  I said  "interferon resistant".



"It appears that non-responders do indeed respond to Telaprevir triple therapy"
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But were they null responders, or were they "non-responders" because they were under-dosed, their dose was reduced or interrupted, etc?  

Co

[zazza]

Non-responders does not tell us if we can do without response to SOC. Null responders does.

[Willy50]

With all due respect.... we may have to re-define what we mean when we call people "non-responders".  It appears that non-responders do indeed respond to Telaprevir triple therapy .  Willy
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http://www.hivandhepatitis.com/2008icr/aasld/docs/111108_a.html

Prove 3 results reported at AASLD 2008 (from 453 genotype 1 ----past TX failures)

"Based on these findings, the investigators stated, "In a population of patients who have failed previous [pegylated interferon/ribavirin] treatment, response rates 12 weeks after end of treatment were 52% overall in the T12/PR 24 arm: 73% in prior relapsers, 41% in prior non-responders."  

(These were SVR 12 results and therefore not "official"-- Willy)

[zazza]

"The virus in your blood is the easiest to kill, because it doesn't live as long as the virus that is in liver cells."

Is this true? I thought an HCV copy was extremely short lived anyway. But that blood cells regenerate in 4 weeks, whereas liver cells regenerate in 300-500 days.

Do you have a link to what you stated in your post? It would be interesting to read the original link.