20 months old patient with respiratory problem. Patient is O+ and antibody screen is negative by gel method at the hospital. Lectin panel was ordered at our lab. Here is our results.

Arachis Hypogea - Patient's cells 4+, Neuraminidase treated cells 4+, Pooled O cells negative

Glycine Soja - Patient's cells neg, Ficin treated cells 4+, Pooled O cells negative

Dolichos biflorus- Patient's cells neg, A1 cells 4+, pooled O cells negative

Salvia Sclarea- Patients cells neg, ficin treated A cells 2+, pooled O cells negative

Pooled adult AB plasma- Patient's cells neg, Neuraminidase treated cells 4+, Pooled O cells negative: test with 6 more sources of AB pooled plasma, all negative with patient's cells and positive with neuraminidase treated cells. 

Pooled cord AB plasma- Patient's cells neg, pooled O cells negative.

Based on above reaction, I can assume this patient has weak form of T polyagglutination, Tk, Th or Tx but I do not know why patient's cells are not reactive with adult plasma. Any thought? Should I incubate at room temp longer ? 

Weird.....Why did they order the lectin work up anyway?  doesn't really look like a polyagglutinable sample from those results - but i don't have very much experience with lectins

I think I would be inclined to do an antibody screen in the cold (thinking auto-anti-I or -i)

On 10/2/2017 at 7:52 AM, galvania said:

Weird.....Why did they order the lectin work up anyway?  doesn't really look like a polyagglutinable sample from those results - but i don't have very much experience with lectins

I think I would be inclined to do an antibody screen in the cold (thinking auto-anti-I or -i)

Hello. sorry about the delayed reply. We worked further on this case and turned out the pooled AB plasma that we have frozen did not react with neuraminidase-treated cells (another aliquot of NeuNac treated cells) but fresh AB plasma did. We did test this patient's cells with fresh AB plasma and got a positive reaction. We have to try not to used frozen/thawed AB pooled plasma for this test in the future

Edited June 14, 20187 yr by dothandar

6 hours ago, dothandar said:

Hello. sorry about the delayed reply. We worked further on this case and turned out the pooled AB plasma that we have frozen did not react with neuraminidase-treated cells (another aliquot of NeuNac treated cells) but fresh AB plasma did. We did test this patient's cells with fresh AB plasma and got a positive reaction. We have to try not to used frozen/thawed AB pooled plasma for this test in the future

why the frozen/thawed AB plasma not react with the treated cells?

and I still don't understand why they thought that this patient was polyagglutining  anyway!

Yan xia- I have no idea why it does not react with a 6 month old frozen/thawed AB plasma but reacted with fresh AB plasma. I treated 3 more sources of cells and they reacted weaker (2+) with this same source of frozen/thawed AB plasma but strong (4+ blasted) with fresh AB plasma. May be anti-T diminishes with storage? 

Galvania- I think docs are suspecting an infection in this baby. 

I have heard of this kind of thing once before in 43 years of working (it was in Scotland), but, SORRY, I don't think anyone ever got to the bottom of the cause.  I realise that doesn't help much!

Regarding the plasma - maybe needed complement to react?

Well, in the case about which I know, it was fresh EDTA plasma that reacted, but stored EDTA plasma that did not, so it couldn't have been the complement, as the Ca⁺⁺. Mn⁺⁺ and Mg⁺⁺ required for the complement cascade had already been chelated in the fresh plasma.

On 7/15/2018 at 12:50 AM, Malcolm Needs said:

Well, in the case about which I know, it was fresh EDTA plasma that reacted, but stored EDTA plasma that did not, so it couldn't have been the complement, as the Ca⁺⁺. Mn⁺⁺ and Mg⁺⁺ required for the complement cascade had already been chelated in the fresh plasma.

This is an interesting thought. Chelating agents may or may not be the cause. The sources of plasma that I have worked with in this case are EDTA as well. It will be an interesting experiment to see if the serum and plasma from the same donors reacted the say way after being stored for a period of time. 

6 minutes ago, dothandar said:

This is an interesting thought. Chelating agents may or may not be the cause. The sources of plasma that I have worked with in this case are EDTA as well. It will be an interesting experiment to see if the serum and plasma from the same donors reacted the say way after being stored for a period of time. 

I sort of agree and also disagree.  If it was complement, then the chelating agent has, for want of a better way of putting it, "poisoned" the system, BUT, that does not rule out a different difference (not great grammar, I admit) between plasma and serum.  An interesting thought on your behalf too!

Edited July 20, 20187 yr by Malcolm Needs

Does old EDTA in solution break down after a while, releasing Ca++ back into the solution?  Somebody must have written a paper on this!

Scott

Not as far as I know Scott, but, in any case, this would mean that the stored plasma would be the one that worked.

Oh!  I had that backwards!  (should have re-read the posts from the beginning!)

What I meant was suppose that some of the Ca++ decayed into titanium-40, thereby releasing the EDTA to further chelate excess Ca++ ?

Scott

sounds a bit too much  like alchemy to me........but I don't pretend to be a chemist

4 minutes ago, galvania said:

sounds a bit too much  like alchemy to me........but I don't pretend to be a chemist

Nor I!

Ah yes!  Al Chemy!  An old school chum of mine.  He still owes me $20...

Scott