You are here

What does antibody testing for Covid tell us ?

Categories:

Hi All,

I guess that a number of us on Forum here have been engaged in antibody testing for Covid either as part of a research project or otherwise?

I have been trying to find out what the results of such a test might tell us ,if anything.My test kit has arrived and I will do the lancet prick on my figure Monday so that the sample does not hang around in the post over the weekend.

I have read that if we test positive to Covid 19 in the antibody test that this will show us that we have been exposed to Covid 19, or have been vaccinated ,or both.If we are given a score, opinion is that the quantity of proteins indicated does not correlate with level of immunity;all it shows is that the higher the score the higher the immune response.

However this is the crux of the issue  because there seem to be  substantial and significant variables to take account of such as :

how long ago were we vaccinated and how many jabs have we had;our age and quite importantly any medication we have been taking.

There are other doubtful considerations such as the  antibodies that we possess can act as an initial line of defence when the virus might attack and when these are depleted we have the back up line of defence from our T cells (the adaptive immune system I presume).So do we really need further tests to assess the level of T cells that we possess?

We are told that the older we are then our immune system is weaker as a result and  we know as CML patients there could be the effect of the tki medication -does it suppress or might act as a line of defence.? So am I correct to be very doubtful in terms of interpreting the antibody test results in any detail?

Many of you might have seen a BBC report from Lancet Infectious Diseases that referred to decline in effectiveness of the vaccine over time.It seems that a lot of the data came from the Zoe Covid Study App.Basically it said that Pfizer declines to 88 % after 1 month and 77 after 5/6 months;AZ declines to 77 % after 1 month and 67 after 4/5 months.The other interesting conclusion was that even when vaccinated we are still able to infect others in the household that have been vaccinated ( 1in 5 chance) or have not been vaccinated (2 in 5 chance).

I stand to be corrected in terms of my reasoning above,so in that respect has  anyone who is being treated for CML and who has had an antibody test had their results interpreted  by a medical practitioner?If so does it tell you anything useful?

Regards

John

 

Hi John,

The following video on the subject of antibodies is interesting (I assume you've seen it) may be interesting for some. https://youtu.be/0CABHpCFcR8

Sandy

Thanks Sandy,

It looks as if the NHS use the anti N test as the anti S one is only available privately at the moment.Also it seems that the N test is better at measuring response to the vaccine.The N test is sometimes referred to as the quantitative antibody test.

If you google "S antibody test " or alternatively "N antibody test" a number of papers and reports will come up explaining further.

One test is purported to be a combined S and N test but may not yet be approved for use by CDC in USA.

I looks as if researchers are still trying to fully understand mechanisms and processes regarding the immune system and Covid 19.

Regards

John

Professor Tim Spector does an excellent job describing the role of antibodies, particularly the difference between N and S antibodies in response to Covid infection or introduction of a vaccine (mRNA spike protein).

What he doesn't discuss and is very important to understand is the role of T-cells in conferring immunity to Covid (and other flu-like virus') and the fact that antibody production alone is not necessarily an indicator of lasting immunity. Having high "S" or "N" antibodies requires interplay between B-cells and T-cells in defense against Covid. And it is the T-cells which are emerging as the long lasting surveillance against future exposure.

In fact, antibodies, initially created, may not last long because they are not needed given T-cell surveillance. And, antibodies, initially created, may not expand to large numbers given T-cell rapid response.

High antibody amount may actually indicate poor T-cell response or low antibody amount does not in itself indicate whether the vaccine (or natural exposure) is working because the vaccine degraded quickly. After all, the vaccine is an invader too!

T-cell testing is likely to give a much better view of what the body is doing both in response to the vaccine and/or natural exposure:

"A growing body of data now demonstrates the importance of both T cells and antibodies in the coordinated immune response against SARS-CoV-2. This method is a further boost to scientists who seek to routinely monitor and assess SARS-CoV-2-specific T-cell responses in vaccinated or convalescent individuals, as well as to test and verify the effectiveness of vaccines."

(and as you all know by now, vitamin D activates T-cells (and B-cells for that matter which create antibodies). It's the T-cell which wallops Covid both in the short term and long term and as importantly - quiets down the inflammation response while doing it and when it's done)

 

Hi John

I was given an anti body test at me treating hospital and the result was half that of a normal healthy person but there is still not a level that i am aware of that is known to be an optimal level or even what level is needed for what protection.  I believe there are a lot of different scales too so unless the result is read by someone who understands the appropriate scale then it may be meaningless.

very few hospitals are testing T cells which act together with the anti bodies and the mix of these in protecting us is also an unknown. A recent webinar i watched suggested AZ was better at T cell production and Pfizer better for anti bodies. Also it was discussed what the benefit is to a patient to know if they have anti bodies or not.  Would you change the way you act based on the result?  If the result is not good what affect would it have on you mentally?

I think there is still so much unknown that i am now sure an anti body test would tell you much about your level of protection.    

Hi Christine,

So with the NHS test you presumably were not given a score?

Looking at some of the private ones such as Roche which some labs use the range in terms of the positive score is from 0.8 u/ml to 2500+ u/ml.However it cannot differentiate whether the antibodies  level relates to previous virus infection or the effect of the vaccine or both.In addition at the moment they dont know at what level antibody protection occurs and very importantly what level of antibodies should exist in the normal or healthy population- so we dont have any control data/levels.

In other countries such as Hong Kong those who wished to leave the country and then return again had to have an antibody test as well as 2 jabs and the score gained influenced the length of quarantine to be required i.e. 7 or 14 days on return ;that procedure  has now been abandoned so a high score no longer gets you shorter quarantine.There has been an issue over reliability of the test and the scores.

Regards

John

Just to emphasize a key point - it's not about antibodies. It's about T-cells.

T-cells is what protects you from Covid (and other respiratory virus'). Vaccine induces an antibody response initially, but it is the T-cell which destroys the virus (and the vaccine too!).

And what activated T-cells? Yep, you all know.