Fewer antibodies with second test: Took my... - CLL Support

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Fewer antibodies with second test

ElMaga profile image

Took my second Antibody test ; while I'm happy I still have antibodies (they were very low to begin with), I now have fewer. I wonder if the ibrutinib contributes to the decline? All other tests are excellent. Remain hopeful that we will learn more. My oncologist also remains positive that his/her vaccinated patients develop a level of protection, as he sees few to any patients with covid, even factoring in how careful we are.

26 Replies

Yes according to other posts, the BTK's can effect. I am sure others will have more detailed explanation.

Zeit profile image
Zeit in reply to GMa27

Had my second test last week. Both the same 0.4.

What are you numbers? My 2 months test showed 55 units/mL antibodies and 4 months after jabs showed 83 units/mL so mine went up. Can you provide more info on your numbers and timings?

ElMaga profile image
ElMaga in reply to E-Lynn

did you go to Labcorp? there numbers are different?

E-Lynn profile image
E-Lynn in reply to ElMaga

Yes. I went to labcorp in San Francisco and my results were U/mL or units per mL, where positive was considered > 0.7. They said antibodies were detected.

I had 5.79 first time; 3.8 this time; I know they are low but that's all I know. My oncologist doesn't make much of these. I think if I weren't on ibrutinib the numbers would have been different as everything else is normal.

Would you please tell me the name of the antibody test? I asked our family doctor about getting a test that would show if I had developed antibodies against COVID 19 and he told me there wasn't a test. I didn't push the issue because I don't know what it is called. Its been 3 months since my 2nd Pfizer shot and I'd really like to know. I see the oncologist next month and want to be armed with the correct question and request. Thanks

newyork8 profile image
newyork8 in reply to Hilomom

Wow...your doctor is misinformed badly. 2 different tests can be performed...ONE --antibodies your body creates to having had exposure to the actual virus....neoclaspid. The other a test for antibodies created by vaccination...so called spike protein S antibody ...test.

SeymourB profile image
SeymourB in reply to Hilomom

Hilomom -

Technically, your doctor is correct. There is no spike antibody test approved for verifying a vaccine outside of clinical trials.

But there are indeed spike antibody tests that you or your doctor can order in the U.S., depending on what state you live in.

The test that LLS is ordering is LabCorp test 164090 - SARS-CoV-2 Semi-Quantitative Total Antibody, Spike:


Note that LabCorp has a warning:

"On May 19, 2021, the FDA issued a safety communication reiterating that "antibody testing should not be used to evaluate a person's level of immunity or protection from COVID-19 at any time, and especially after the person received a COVID-19 vaccination." Visit fda.gov/medical-devices/saf... for more information."

Quest Diagnostics has 2 spike antibody tests. I've done the first one at the same time as the above LabCorp test. Both came up negative.

Quest test code 34499 - SARS-CoV-2 Antibody (IgG), Spike, Semi-Quantitative:


SARS-CoV-2 Total Antibody, Spike, Semi-Quantitative (test code 39820)


I believe that test 39820 is the same test that LabCorp does, while 34499 is on a different laboratory instrument, and it's numbers are not exactly comparable to LabCorp.

Their FAQ has additional info - look for notes for each of the above test codes:


There is a warning on test 34499:

"This positive result means that an individual has developed an immune response to recent/prior SARS-CoV-2 infection within the limit of detection of the assay. Positive results may also occur after a COVID-19 vaccination, but the clinical significance is not yet known. There are currently no FDA authorized tests for individuals who have received a COVID-19 vaccination, and the performance characteristics of the authorized antibody tests have not been established for these individuals. Since much is still not known about the body’s immune response to this virus, this test result cannot be used to indicate a level of immunity or rule out the chance for reinfection."

Note that a positive result on any of these only indicates that your have as many antibodies as a pool of PCR positive patients had. They do not indicate any specific level of protection. Some of the PCR positive patients may have died or had serious disease.

There's also a matter of timing. Ideally, you should do spike antibody testing within 2 - 6 weeks of the last dose of vaccine, because antibodies rise to a peak, and then begin a slow decline.

If none of your doctors wants to order the test, both Quest and LabCorp have ways to order the tests yourself online in most states in the U.S. LabCorp will not do consumer online testing in NY, NJ, RI, MD and MA, and Quest will not do it in NY, NJ, and RI. Send me a chat message if you want to know more.

Antibody tests are fascinating, nevertheless. I knew that I scored badly on pneumococcal pneumonia antibody tests, so you'd think I would be emotionally ready. I was so happy when I got the vaccine, I nearly cried. I found that a negative result on the spike antibody tests led to some additional depression. I felt very vulnerable. But then, positive results came back from the Adaptive Biotechnologies T-Detect test that I had paid for myself out of pocket ($219). T-Detect tests T-cell response. Again, a positive result does not indicate protection. But I felt that I was not completely defenseless. I don't feel at all protected, though.

So, I see these tests as largely emotional tests for now. The Leukemia Lymphoma Society study will eventually publish results that may provide some general indications of protection. But we'll each still have our own CLL markers, treatment, and history to confound things.

At best, positive results let us emotionally relax a bit. But we should still be cautious in practice, I think.


Pin57 profile image
Pin57 in reply to SeymourB

SeymourB - your reply is the best explanation I’ve read about “what these test scores mean”. Much better than LabCorp’s explanation that basically says “we don’t know what the scores mean”, leaving test people (like me) wondering why post the scores until you can explain better what they mean? …. especially regarding the key topic of level of protection? Someday, we may hear?

Thank you again for sharing your in-depth knowledge and I especially liked your summary that these are “emotional tests”. Indeed they are that!

Billhere profile image
Billhere in reply to SeymourB

Darn! Seymour you’re very helpful!!

Hilomom profile image
Hilomom in reply to SeymourB

Thank you for your very thorough answer. Now I have some needed answers.

ElMaga profile image
ElMaga in reply to SeymourB

how did you get the Adaptive Biotechnologies T-Detect test that I had paid for myself out of pocket ($219). T-Detect tests T-cell response.?

SeymourB profile image
SeymourB in reply to ElMaga

ElMaga -

They market the T-Direct to the consumer:


I was skeptical of the test at first. Their FDA emergency authorization checks out, and it turns out this test has been a long time coming, and there are several papers on the general principle and the test itself. It holds promise for all kinds of immunology research, But I'm disappointed that it's qualitative - pass/fail. I was hoping for something numeric, and info on which antigens the T-cells respond to.

Interestingly, Adaptive Biotechnologies is the same company that's doing the clonoSEQ test for MRD measurement after treatment. That test is not direct to consumer.



DUKELAXDAD profile image
DUKELAXDAD in reply to Hilomom

Labcorp test 164090Semi qualitative antibody test.

Free if you have insurance otherwise $10

My antibody test was at Quest, and the result came in < 100 which their descriptions reports as No Antibodies.

SeymourB profile image
SeymourB in reply to wizzard166

wizzard166 -

I did that Quest test in addition to the LabCorp test. It runs on a different laboratory instrument, so it has different index values. As a result, we can't compare the numeric values between the Quest and the LabCorp spike tests. The pass-fail result should be roughly comparable, though.


wizzard166 profile image
wizzard166 in reply to SeymourB

So if I'm understanding your reply, you didnt say you got a positive antibody test from Labcorp and the same zero I got with Quest. All you are saying is that the two use different grading mechanisms, but ultimately the results should show the same result. you started by mentioning you took both, so at first i was thinking you were giving me hope because the Labcorp showed antibodies but the Quest you took did not.

SeymourB profile image
SeymourB in reply to wizzard166

That's correct - no antibodies detected on 4 SARS-CoV-2 antibody tests back in April - nucleocapsid from both Quest and LabCorp, and no antibodies on spike IgG from both Quest and LabCorp. I repeated the LabCorp nucleocapsid and spike IgG, and still no antibodies.

I cannot imagine that antibodies will magically arise for me this long after the vaccine, which was in February. I may repeat the T-Detect test at some point to see if it still detects T-cell receptors to SARS-CoV-2. I would have to pay for it out of pocket ($217). It would be N=1 sort of info, and would not mean that I'm protected against any particular level of infection. We need both antibodies and T-cells to fight the virus (and NK cells, and neutrophils).

Sorry for any wording ambiguities. Sometimes a table of results is clearer, but it's hard to do in the HealthUnlocked editor.


wizzard166 profile image
wizzard166 in reply to SeymourB

Hey Seymour

I understood it Seymour, I'm just irritated and sad that others get antibody results and I get zero.

The weird thing is that I have never been infected with COVID, not that I'm complaining. So I have zero antibodies detected from being vaccinated, yet I stay uninfected after running around doing things that would make others faint at the thought. On New Years my wife and I were at Sea World in Orlando, the place was packed body to body with Spanish music and wild dancing, and people slurping beer all over the place. Prior to that in October we went for four days to the four Disneyworld parks. I've been going with my wife on many three day weekends, in addition to two week trips, and we have stayed in dozens of hotels. We have gone dining throughout both indoor and outdoor. Yes I've worn a mask on many occasions, and my wife forces me to use hand sanitizer whenever she is with me, and yells at me if I touch my eyes.

Some would say its dumb luck, and that is why I've been free of infection. I say that with no antibodies at all to COVID, there is no such thing as that much luck. That is like saying I walked blindfolded on I95, or the Long Island Distressway, with a mask on and some how in rush hour never got hit. I think there are people both with and without good immune systems who for whatever reason are totally protected from this specific virus. Too many stories of a spouse caring for the other spouse in their bedroom, until that other spouse was hospitalized, yet the one caring for them never got sick. There is something else besides antibodies for this specific virus that either protects or doesnt protect people.


SeymourB profile image
SeymourB in reply to wizzard166

wizzard166 -

The lack of antibodies does not mean you haven't been infected. The lack of antibodies is probably a result of your CLL.

SARS-CoV-2 is not as infectious as, say, norovirus or measles.

You could have had 1 or more asymptomatic infections that were knocked back enough by innate immune cells like NK cells, plus cytotoxic T-cells. Severity of infection depends in part on total number of virions ingested.

You might be slightly less susceptible than others based on blood group (Type A is more susceptible) or other constitutional or genetic traits. Most of the genetic studies that I've seen were focused on why some people got really bad disease, not on what alleles are protective. I may look into that more.

You may have better habits than most people who get infected. Or a more vigilant wife. 😄

The places you go may not be representative of the most risky places at any given time. They may also check temperatures or mandate masking that reduces risk. They may have been outdoors, which is less risky. Avoid taking meals in elevators.

You may be lucky. Do you bet on horses?


wizzard166 profile image
wizzard166 in reply to SeymourB

I used to be a great handicapper of horses, which is where my nickname the Wizard comes from. A funny story is that when I was called the Wizard by a few people at the Track, I liked it and started using that name in many of my ID selections for different things; however, I spelled it Wizzard. It wasnt until a number of years later, when I named my team in a Fantasy Football League (formed around 23 years ago, and still one of the founding members) The Wizzards, that another League Member told me I spelled it wrong. Now my Son and I still are The Wizzards in that League, and I continue to this day spelling it that way in my IDs

My Blood type is the rare A-, so that probably isnt it. There has to be some factor that is common with the mass of people who have clearly been exposed and who do not come down with a serious infection from COVID. My great weakness lifetime has been Respiratory infections, my IgG and IgA and IgM are all very low, and I'm a bit overweight. Something doesnt fit. And when something doesnt fit, a good handicapper knows something is up. There are too many people who go face to face with very ill Covid patients, both family and professional, who never get sick from the bug. I just have a feeling that something in the blood or tissue chemistry of that mass of people is a clue to what is protecting that group.


where do you go to get the Adaptive Biotechnologies T-Detect test that I had paid for myself out of pocket ($219). T-Detect tests T-cell response.

SeymourB profile image
SeymourB in reply to ElMaga

ElMaga -

Adaptive Biotechnologies markets T-Detect directly to the consumer:


They provide the prescription through PWNhealth.com, and order the blood draw through LabCorp.

They're also the company that markets clonoSEQ for MRD testing of CLL:


But clonoSEQ is not direct to consumer. Their Physician Finder Tool is strange


I read something that said if you get Covid go right away to the ER and get a clonal antibody cocktail infused and this will help you get through Covid. Have you heard this?

Well, just to add to the confusion. My first LLS tests came back as NEGATIVE to having COVID (Nucleocapsid) and my Semi-Quant Total test showed .4, which was under the POSITIVE range of above .7. Yesterday I had my 2nd LLS test and it came back as POSITIVE for have COVID, and antibody level was 2.7. To my knowledge I have NOT have COVID in the last 3 months, and have not had another vaccine in that time period. HOWEVER, the day before I had my LabCorp appointment I had an infusion of IVIG. There has been some anecdotal talk of IVIG possibly having some COVID antibodies in them, but no indication of what that actually may mean for future protection. Because IVIG production is from blood products that may have been taken 6-12 months ago, it seems likely that the IVIG that is now available might have some COVID antibodies in it. It appears that has happened to me.Terry

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