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Re: Tysabri "rebound"

Posted: Wed Sep 09, 2009 10:06 pm
by NHE
A couple of months ago I went to one of those Biogen sponsored talks (it was really a Tysabri sales seminar but don't tell all the patients that). Anyways, the doctor, a neurologist with MS who is also on Tysabri (the perfect salesman), discussed Tysabri rebound in reference to PML. This is from my notes of the talk...
  • PML:
    There’s a danger of PML if the CD4 count gets below 400.
    Touch program, and/or Dr. M, monitors CD4 count.
    Patient is off of Tysabri if CD4 count is less than 500.
    If PML is determined, treatment is plasma exchange 5x over a 10 day period. Steroids are given 10 days after plasma exchange in order to prevent massive brain inflammation from the immune system’s attack on the PML virus (immune system rebound inflammation aka IRIS, actually Immune Reconstitution Inflammatory Syndrome).
I hope this info is helpful.

NHE

Posted: Thu Sep 10, 2009 2:50 am
by Loobie
What is CD4?

Posted: Thu Sep 10, 2009 1:25 pm
by sou
Hi.

CD4 is a protein characterizing Thelper lymphocytes. It is so characteristic of them that the terms CD4 and Th lymphocytes are used interchangeably.

CD4 = Th

HTH,

sou

Re: Tysabri rebound

Posted: Thu Sep 10, 2009 2:39 pm
by NHE
Loobie wrote:What is CD4?
Among the different types of T cells, there are CD4+ T cells and CD8+ T cells which are commonly discussed in MS research. CD4+ T cells are referred to as helper t-lymphocytes. They are involved in recruiting and activating B cells and marcophages. B cells, once activated, transform into plasma cells which produce antibodies. CD8+ T cells are referred to as cytotoxic t-lymphocytes which primarily destroy virus infected cells. I'm sure that the above discussion has been oversimplified. Though, the point was that the Touch program monitors patient's CD4+ T cell levels as they can get too low in response to PML. In addition, immune system rebound, IRIS, is a recognized problem with patients with high levels of JC virus. The fact that it's helpful to give patients steroids to reduce immune system activity suggests that the inflammation from the immune system may be more damaging than the virus. Or, it could be that the immune system over responds creating too much inflammation which results in tissue damage.

NHE

Posted: Thu Sep 10, 2009 2:42 pm
by Loobie
Thank you very much.

Posted: Thu Sep 10, 2009 2:49 pm
by cheerleader
Understanding tysabri rebound and PML in the CCSVI paradigm could also be as easy as recognizing that microbleeding thru damaged venules allows for deposition of viral cells and other unwanted guests directly into the brain tissue- and a compromised immune system with low CD4 and T cells is then unable to deal with the assault.
cheer

Posted: Thu Sep 10, 2009 8:54 pm
by prof8
NHE, you said that Touch monitors CD4 cells to keep ahead of PML. I have never heard of this and have been on Tysabri for awhile. I haven't read this as a requirement of Touch. My own neuro (who has MS and is on Tysabri!) checks my blood for PML every 3 months. But I'm not aware of any other testing. Can you give more information? Thanks!!

Tysabri "rebound"

Posted: Fri Sep 11, 2009 12:23 am
by NHE
prof8 wrote:NHE, you said that Touch monitors CD4 cells to keep ahead of PML. I have never heard of this and have been on Tysabri for awhile. I haven't read this as a requirement of Touch. My own neuro (who has MS and is on Tysabri!) checks my blood for PML every 3 months. But I'm not aware of any other testing. Can you give more information? Thanks!!
I wish I could give you more information. However, all I seem to have is the quote from the doctor. It makes me wonder, by the way, how many neurologists with MS and on Tysabri there can be? Probably not too many. Are your neurologist's intitials V.M.? Anyways, I tried to find some more info on the CD4 quote by looking in the prescribing information but wasn't able to find it. Perhaps that would be a good question for the next time you visit your doctor (or you could always email if they are the type to respond to emails).

NHE

Posted: Fri Sep 11, 2009 3:48 am
by Loobie
The program where they are checking your blood frequently is called "TYGRIS". What it stands for I don't know, but I know it's a seperate program than TOUCH which deal with the prescribing portion of it.

Posted: Fri Sep 11, 2009 10:20 am
by prof8
Nope, my neuro's initials aren't VM. Anyhow I have an appointment with her next week so I will ask what she knows about this. Thanks!