banter and General Discussion, page-4605

Sorry for the delay in getting back to you on this dachopper - this bit you wrote is making things trickey -

You wrote :

For those that don't know what this is, picture the MSC cell, as a hypothetical human, with a human arm with fingers on it, and those fingers on the right arm are the TNF receptor 1. shRNA silencing from what I understand, places something onto / in the metaphorical hand of the TNF recepter 1, so that it can no longer have it's fingers free to do what it does, like sense the presence of activated T cells, and then get the MSC to secrete molecules that either de-activate the T cell, or downramp the production rate of T cells activation.

Its generous and inclusive probably for you to have done, I think you are trying to bring readers with less science along, but the science understanding implied in your analogy has some serious problems in it.

You post has lots of ticks of appreciation, and I like its structure myself. And I like that you are trying to drill down.

But what the above implies needs to be corrected. You and I won't make sense of the figures and statements in your post together before we address the misunderstandings implied in that bolded bit I've excerpted from your post.

If you want to continue this discussion perhaps you might prefer to do so off list (just drop an email in the reply and I'll pick it up and cut and paste into the reply)? Otherwise I have to show why the above is a problem.

Very briefly for readers. TNFR1 expression is measured by the use of antibodies in flow cytometry or ELISA. Thats one technology. TNFR1 gene expression can be knocked down by shRNA silencing that is quite a separate technology. To make sense of the figures and the quotes in dachoppers post will require an understanding of both technologies and the analogy dachopper is using, I believe charitably out of a desire to include readers, is kind of blending them together.

The TNFR1 receptor does not sense activated T cells. Its ligand is TNFalpha from activated macrophages. I don't think T cells even secrete TNFalpha or that MSB has ever claimed that they do.