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Hi Greg,
Your explanations have been easily interpreted and I thank you so much for spending the time with me.
Are you saying that the HerpesSelect Elisa may allow for cross-contamination due to the high volume of tests performed at once? I did previously call Focus and was told that the accuracy is the same as the Immunoblot but I can certainly see that would depend on cross-contamination, the lab and tech performing the test, etc...
Also I have read a ton on the other tests you mentioned and although they (along with a few other tests) claim to be type-specific, they truly are not. They are wrong in specification of type 40-60% of the time and often they miss HSV-2 altogether. This is due to the method they use of crude antigen (whatever the heck that means :o)). Therefore, the only truly type-specific highly accurate tests available today are: Western Blot, HerpesSelect (Immunoblot and Elisa) and there is one called the Point of Care aka POCKIT that detects antibodies to HSV-2 only. This test is done in a doctors office via a finger prick and the results are available within six minutes. I believe this test has an accuracy rate of 91-98%. I think that percentage accounts for people who have not waited the proper time for the antibodies to be detected in their body.
I will try to obtain a Western Blot because I want to know my status for HSV-1 as well as HSV-2. If I am running into too many obstacles, can I feel confident with HerpesSelect?
Thanks again!
In Reply to: TO GREG posted by Antibody question on March 14, 2002 at 10:49:10:
"Your explanations have been easily interpreted and I thank you so much for spending the time with me. "
You're welcome .. please bear in mind that I am by no means a virologist .. we just use viruses and antibodies for research purposes.
"Also I have read a ton on the other tests you mentioned and although they (along with a few other tests) claim to be type-specific"
I know ... they are NOT specific at all.
“This is due to the method they use of crude antigen (whatever the heck that means :o))”
It means that they use antigens (part of the viral coat protein = capsid) that have not been purified properly, often because they are difficult to separate from all the other proteins. What the Focus Technology guys have done is isolated the viral gene that encodes for the viral capsid protein and used recombinant DNA technology to produce the protein (=antigen) in a highly pure form. They isolate the gene, put it into a vector (a peace of circular DNA) and infect a bacterium (commonly E. Coli) with it, the bacterium takes up the gene and starts producing the protein (=antigen). The protein is secreted by the bacterium into the growth/nutrient medium. This makes it much easier to purify the protein. Therefore they get better results.
"Are you saying that the HerpesSelect Elisa may allow for cross-contamination due to the high volume of tests performed at once? I did previously call Focus and was told that the accuracy is the same as the Immunoblot but I can certainly see that would depend on cross-contamination, the lab and tech performing the test, etc..."
That is certainly true...one of the common analytical errors in biochemical analysis is called "operator error". Cross-contamination is usually not a problem in ELISA 96 well plates, unless the technician is sloppy. I was referring to ELISA being used in labs that have to process large numbers of patient samples .. ELISA can be fully automated; cutting down on sample preparation and analysis time ...blotting procedures are more time consuming. If the ELISA is as good as the Immunoblot .. you could order that test if you want, but if it were ME, I'd rather have a good Virological lab do a Western Blot.
“If I am running into too many obstacles, can I feel confident with HerpesSelect?”
Yes you can .. it beats all the other tests.
Good luck
GregD
(Biochemist/Cell Biologist)
In Reply to: Re: TO GREG posted by GregD on March 14, 2002 at 12:18:16:
Hi again,
I'm going to really push for the Western Blot. Unfortunately, the only lab who will perform this procedure for HSV-1 and HSV-2 is in Washington state.
I'm a bit nervous to have the test only because I have read a lot about the simplex virus and it seems that it is causing more complication and trouble within the body than once thought (both forms of herpes simplex). However, I have also read that by the time a person is 70-years-old, chances of being infected with HSV-1 is 90%. That means that a lot of healthy people are living with this virus and that aspect does ease my mind. In addition, I have learned that HSV-1 does NOT protect a person from acquiring HSV-2 so 10% of the population have antibodies to both. UGH! HSV-2 does protect from acquiring HSV-1 though. I wonder why that is? Is HSV-2 just stronger?
In Reply to: Re: TO GREG posted by Antibody question on March 14, 2002 at 13:58:11:
"I'm going to really push for the Western Blot. Unfortunately, the only lab who will perform this procedure for HSV-1 and HSV-2 is in Washington state."
Would be your best option and don't worry...we often ship blood samples from Europe to the States .. provided that the samples are prepared and shipped correctly no problems may be expected.
"However, I have also read that by the time a person is 70-years-old, chances of being infected with HSV-1 is 90%."
Well this is just a bit of Doomsday thinking but could well be. I read recently that they are working on a vaccine for HSV (can't recall which type). This would be our best shot at wiping it out...so I am keeping my fingers crossed that a suitable vaccine will be available soon .. won't help those who are infected, but it will stop the spreading of the disease. It worked great for small pox .. just hope that no Bin laden type gets their hands on it. That is one of the main reasons why I signed the petition against the destruction of the small pox samples (no known outbreaks have been reported worldwide for decades), which are kept at the CDC in the 90's (there are only 2 left...1 sample is kept at the CDC and 1 sample is kept by the Russians). If we had destroyed it, we wouldn't be doing any research into it anymore (now that it is suspected that possibly Irak is producing it). Furthermore, the small pox virus is the master of them all. It so cleverly tricks the immune system into not responding or recognizing it .. just think what we can learn from it with regard to HIV or Ebola. Let me illustrate how clever a virus can be:
If a virus infects a cell, the cell starts producing so-called SOS proteins. These proteins are released outside the cell and once they reach neighbouring cells, they bind to a receptor on the cell's surface. This instructs the cell to go into apoptosis. Apoptosis is programmed cell death...it is in fact a self-destruction program...this prevents the virus from spreading and gives the immune system time to respond to the threat. Now what does the small pox virus do?? It reprograms the infected cell to start producing part of the receptor (only the part that binds the SOS protein) and the cell starts releasing those. Now….before the SOS protein reaches another unaffected cell, the fake receptor binds it outside the cell and the self-destruction signal is no longer triggered. Clever isn't it?
"HSV-2 does protect from acquiring HSV-1 though. I wonder why that is? Is HSV-2 just stronger?"
I have no idea why that is.
Good luck
GregD
In Reply to: Re: TO GREG posted by GregD on March 14, 2002 at 16:57:04:
I didn't know you were writing from Europe. Thank goodness for scientists such as you to keep MAD scientists in check :o)!
I had no idea why small pox was so deadly. What a very clever little virus! Hopefully in time we will be able to decode HIV, small pox, herpes, etc...I do realize that day is very far away but I have faith.
I too am hoping for a vaccine for HSV. Studies have been done where people are well-informed of the virus, how it can be contracted, ways to possibly avoid it, etc....and many still acquire it. That just proves that the only way to decrease the spread is to vaccinate. I guess a similar analogy is how we all know that it's unsafe to drive without a seatbelt, yet many of us do not wear them and put our lives at risk daily.
If you have time (and I realize you are not a virologis) can you explain how we came up with a vaccine for chicken pox but have not been able to do the same for a family member, the herpes simplex virus?
It's been so great learning from you and chatting.
Thank you!
In Reply to: Re: TO GREG posted by Antibody question on March 14, 2002 at 18:51:49:
"I didn't know you were writing from Europe."
Yep, I am writing from Holland
"Thank goodness for scientists such as you to keep MAD scientists in check :o)!"
No not one scientist was involved in that decision. It was decided by politicians, because they were afraid that terrorists could get their hands on it (what a load of bull, it's in an extremely high security lab, other deadly viruses are easier to obtain .. but even if Saddam has the small pox virus, thank God we didn’t destroy it). We were ALL against it (Most of these decisions are made by people who haven’t got any clue what they are talking about, but the general public perceives this as if the scientists are behind it) and I ‘m not even a virologist. Our main reason was... just because there hasn't been a case of small pox for decades and the vaccination program was so successful, doesn't mean that somewhere, in some remote part of the world, the bug hasn't survived (we have no guaranty that it was completely wiped out). If we stop the research, we will be taken by surprise, once it again jumps from its original host (= unknown) to humans, or in fact if any terrorist organisation gets it. The only 2 labs in the world that have the virus are high security labs (as in the film "outbreak"), with just as much security to keep unwanted people out. No, it is much easier and less of a risk to any terrorist to use something like Anthrax. Easily obtained from cow dung, easy to produce, with a little knowledge of biology and in most cases lethal. The second reason was: .. just because the pox virus is so cleaver in tricking the human immune system, we could learn a lot from it…and that knowledge could potentially be beneficial in the war against Herpes, HIV and Ebola.
“I had no idea why small pox was so deadly. What a very clever little virus! Hopefully in time we will be able to decode HIV, small pox, herpes, etc...I do realize that day is very far away but I have faith.”
Oh yeah .. it’s an interesting little bug. They now know that it has at least 20 homologies in its viral DNA to our human DNA. This means that it shares at least 20 genes or parts of genes with us humans. Now here is the interesting thing … all of these genes are genes encoding for proteins involved in the human immune system ..so we are guessing that it has many more tricks up its sleeve to trick our immune system. It acquired this knowledge by mutating into a form, which makes it more resistant and us humans, a good alternative host organism to its original host. I am convinced that we will see a great leap in fighting viruses the next decade or so …especially now that the human genome has been mapped and the whole proteomics field is exploding .. it is the field of molecular cell biology that deals with determining which protein is encoded by which part of our DNA and its biological function in our metabolism. It will definitely allow a more targeted approach to medicine, but also allow a better prevention of diseases developing, by adjusting the way children grow up (not only through the right diet, but this must be the major factor). I won’t say that it won’t cause problems or even abuse or knowledge with, for instance, acquiring a job or insurance .. but this is something the politicians and ethicists need to deal with and pass laws that will protect the individual;.
“I too am hoping for a vaccine for HSV. Studies have been done where people are well-informed of the virus, how it can be contracted, ways to possibly avoid it, etc....and many still acquire it. That just proves that the only way to decrease the spread is to vaccinate”
Yes .. the best strategy is still through vaccination and a good prevention by limiting sexual partners and using the right protection. Did you know that there is even an experimental HIV vaccine available, but most scientists feel that the risk is still too great. Not only will you become seropositive, because you’ll start producing antibodies against it (
In Reply to: Re: TO GREG posted by GregD on March 15, 2002 at 13:31:26:
Greg, Are you familiar with research which strongly indicates that HIV alone DOES NOT cause AIDS -- it is a combination of HIV + HHV6a (herpes virus)?
In Reply to: Re: TO GREG posted by Yancy on March 15, 2002 at 18:14:10:
Yes I am to some extent (I'm not a virologist, but viruses fascinate me immensely, just because they are no true living organisms, but are so cleverly engineered by nature..some scientists think that they are remnants of nature's first attempt in creating living organisms)...as far as "strong" evidence, there is still no scientific consensus, just because it is still not fully known how HIV works...it might well be that HHV-6A facilitates the infection by HIV.. the same mechanism is also proposed for HHV-7, a different strain.
HHV-6A is a member of the beta-herpesvirinae subfamily, is highly seroprevalent, has a worldwide distribution, and infection usually occurs within the first two years of life. The virus is predominantly T lymphotropic (which means it infects T-lymphocytes, white blood cells) although it can infect a variety of cell types in vitro (literally: in glass …i.e. in the test tube or cell culture dish) and CD46 has recently been identified as a cellular receptor. The virus persists in the host, with a latent state proposed in monocytes and bone marrow progenitor cells, and chronic infection in salivary glands.
HHV-6A in vitro augments expression of CD4 molecules on the surface of immune cells, facilitates HIV replication and cell death in dual infections. It is hardly known whether these processes take place in vivo (in living organisms); does HHV-6A enhance HIV infection and AIDS progression? Still unknown. But it could well be that once an individual is infect with HHV-6A during childhood that this predisposes the individual in later life, when sexually active, to a much higher risk of contracting HIV, when HHV-6A seronegative individuals would still be able to fight off the HIV virus and thus NOT become HIV seropositive.
Publications on the subject are still scarse. I’ve come across only a handful (15 or so) in recent years.
GregD
(Biochemist/Cell Biologist)
In Reply to: Re: TO GREG posted by Yancy on March 15, 2002 at 18:14:10:
Since they both invade essential immune cells, it might well be that it is a combined effort of both that leads to AIDS.
On the other hand, it hasn't been shown that an individual who was HHV-6A seropositive, subsequently contracted HIV in later life ended up with full blown AIDS, simply because it is difficult to establish or follow this.
HIV seropositive patients are often also seropositive with respect to viruses from the HERPES family, so again no distinction can be made .. which came first the chicken or the egg, or did they both come at the same time??? Hope that this will be resolved in the next few years.
Just wanted to add this
GregD
In Reply to: Re: TO GREG posted by GregD on March 15, 2002 at 19:15:29:
Thanks, GregD.
Namaste`
Walt
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