This is huge!

[Luap001]

Now it appears a rapid T-cell test has been developed that determines whether one has a longer (relative to antibodies) term immunity against COVID. So this is for people who have been infected and recovered as well as those post vaccination by at least two weeks. It is a tool that will help us to understand the duration of immunity post infection/vaccination. And perhaps it may help the CLL community learn the extent to which at least some of us may mount a T-cell defense and this is of course of particular interest when the post vaccination antibody response is lacking.

dropbox.com/s/d77e5lgy47ens...

[cajunjeff]

We definitely need a t-cell test and this is great news.

The emergency use authorization (EUA) appears to be just for people who have had covid. Where can the information that this test is also for people two weeks post covid vaccination? I could not find that language in the article, but might have juts overlooked it. .

[Luap001 in reply to cajunjeff]

The language is not specifically there; however, we have been advised that you reach “full immunity” two weeks following completion of your vaccination protocol. And likewise for the infected and recovered: You should no longer be infectious two weeks following the later of a positive COVID test or cessation of symptoms. So it stands to reason given too that the response interviewed infectious disease specialists have often given regarding the duration of immunity of both the recovered and the vaccinated is that “we don’t know yet considering that there may be a durable T cell response” and then they add “but this is difficult to test.” Perhaps no longer is it so.

[cajunjeff in reply to Luap001]

I agree with your logic and I assume that eventually some covid t-cell test will be available for us to see if our vaccinations work.

As I read the article you link to, however, it appears this test is only available through an emergency use authorization (EUA). If that is the case, to my understanding you have to look to language of the EUA to see who is eligible to have the test. Right now that would only be for people infected and recovered from covid, not for people looking to test the efficacy of their vaccines.

Doctors in general can prescribe approved tests and medications to us "off label" if they want. But this test only has emergency approval and I dont think our doctors can give it to us off label to check the efficacy of our vaccines.

It is still good and useful information and provides hope that a T-cell test will soon be approved for us.

[Luap001 in reply to cajunjeff]

You are likely right. Perhaps ASH and LLS could lobby on behalf of those with blood cancers that have been vaccinated regards eligibility. I think the CLL specialists have the “activist gene” in them, wouldn’t you say? In any case, such eligibility really should not be controversial.

[cajunjeff in reply to Luap001]

I agree 100%. Those of us with cll are a relatively small group and I dont think much attention at all is paid to the fact that the vaccines might not work for many of us.

I can understand why the FDA should be very cautious in giving emergency use authorization (EUA) not drugs or vaccines we take for covid. Safety is a paramount issue.

Insofar as tests like the one here, the FDA should make the approval broader to include us. Its just a blood test, there is no safety issue. I cannot think of any good reason the EUA in this case should not have included immuno-compromised people who have been vaccinated and want to assess if they are getting t-cell protection from the vaccine.

I would take that test tomorrow if I could.

[AussieNeil Partner Administrator in reply to cajunjeff]

From: Susan LECLAIR as published in the CLL/SLL groups.io community

Date: Tue, 18 May 2021 04:58:47 ACST

T cell testing is difficult to do. For the most part, it tests for large qroups using marker testing such as CD4 or CD20. While additional testing can assess for the cell's DNA to respond, it does not test for "but will it respond". Most of these are qualitative so your answer will be something like - it looks as if the T cells can respond".

Susan Leclair

[Sojomama13 in reply to AussieNeil]

That is very interesting Neil. Thanks for sharing. Sandy

[SeymourB in reply to Luap001]

Luap001 -

Full immunity is not reach until 4 weeks.

ashpublications.org/blood/a...

Good enough immunity may be reached in normal people by 2 weeks following the 2nd dose of the mRNA vaccines.

I wish someone would compile all the antibody evidence into a time series chart, with references.

=seymour=

[Davidcara]

There has been a covid vaccine T cell test in the USA for a while. Look for T Detect by Adaptive. Runs about $150.

[SofiaDeo in reply to Davidcara]

No, that test is for post-infection assessment, not post vaccination assessment. We still don't know if the "post infection" cell responses are identical to the "post vaccination" ones. Time will tell if they are the same, or not.

[Davidcara]

Interesting, the T Detect website use to state, would detect T cell response post vaccine. Now I cannot find that on the website.

[SofiaDeo in reply to Davidcara]

Someone may have discovered the website error and changed it, I bet!

[bennevisplace]

Interesting, thanks.

A different T cell response test has been authorised by the MHRA for use in the UK. So far it's only available privately med-technews.com/news/Covid... but that could mean anyone willing to pay can have the test.

[bennevisplace]

Further to my reply above, I learned that the test I referenced is the T cell test being used in the COM-COV trial, in which some of our members are participating globenewswire.com/news-rele...

COM-COV is investigating immune response to vaccines.

[SeymourB in reply to bennevisplace]

I think T-Spot is a different test, but probably works in a similar way.

=seymour=

[SeymourB]

I made a post on the CLLSLL email list about this recently. Here's an edited copy of my post:

This is why Adaptive Biotechnologies' T-Detect is so promising. They do next gen sequencing of the beta chain of the T-cell receptor itself. They then compare the result to a database to determine what it hypermutated to match. For the T-Detect, they look for sequences that match SARS-CoV-2 epitopes.

t-detect.com/

This is a direct to U.S. consumer test.

fda.gov/news-events/press-a...

March 5, 2021 FDA press release

fda.gov/media/146481/download

EMERGENCY USE AUTHORIZATION (EUA) SUMMARY

fda.gov/media/146479/download

FACT SHEET FOR HEALTHCARE PROVIDERS

fda.gov/media/146480/download

FACT SHEET FOR RECIPIENTS

medrxiv.org/content/10.1101...

Clinical Validation of a Novel T-cell Receptor Sequencing Assay for Identification of Recent or Prior SARS-CoV-2 Infection (pre-print)

twitter.com/RolandBakerIII/...

Twitter thread with links to T-cell sequencing research papers. In particular:

ncbi.nlm.nih.gov/pmc/articl...

Magnitude and Dynamics of the T-Cell Response to SARS-CoV-2 Infection at Both Individual and Population Levels

I'm disappointed that the test does not provide quantitative results, nor list which proteins the TCR matched. I think they're hoping to gauge the demand. They also clearly were not expecting people to use it after vaccination. Even though both the Quest and LabCorp spike IgG semi-quantitative tests were negative for me, the T-Detect did detect a response - not that that means I have any effective protection.

But I felt a little more hopeful that some of my wacky lymphocytes are doing something properly.

=seymour=

[SofiaDeo in reply to SeymourB]

I think if one is not prone to constant infections, there is some degree of functional immunity. HIV disease statistics show this concept....when people with that disease immunity' is low enough, they get routine opportunistic as well as pathogenic infections. I had a number of HIV positive patient who got 6-8 infections yearly! When their CD4 count got below a certain level, prophylactic drugs were given.

So I interpret my own disease immunosuppression this way. There are people here who state they get IgIV routinely or else they get infections. They obviously have a more stressed immune system than I, who do not need IgIV yet.

[SeymourB in reply to SofiaDeo]

I agree in general. In some ways, we are in the opposite boat to HIV. Where they have T-cell dysfunction, we have B-cell. But the 2 cell types are not truly opposite in function or net effect, I think.

There are other cells that get called to fight viruses besides B-cells. So, we are not entirely naked in a bramble patch if we do not make antibodies. But the antibodies surely do help, and could make the difference between a life threatening infection by a serious pathogen, vs. a lot of time in bed.

Plus, without antibodies, we get to experience the infection by the same pathogen over and over, and it could become chronic. The T-cell response means that we may respond a little quicker, but without the antibodies, I'm thinking the benefit is not that great.

These new T-cell tests will provide for much more research on total immune function, and may help explain why one person gets really sick or dies, and another is asymptomatic or mildly ill. That research benefit will take some years to arrive, I'm afraid.

=seymour=

[bennevisplace]

I was just looking for something else and came across this article bookmarked 6 months ago, from Adaptive Biotech before they got the EUA

adaptivebiotech.com/2020/09...