anti jkb

[newBB]

i have qeustion about NEQAS my friend shared with me the sample from NEQAS i dont remember which month was it ( It was for learning purpose), i run both on gel card methold the planel to identify the antidibodies . so the coombs panel there is reaaction but in enzyme there is on reaciton , because of the reactoin in enzyem i could not say is anti jkb ! but my friend siad in NEQAS they are tricky they want to confuse you . when the result came out it was anti Jkb . but i dont know why no reaction in enzyme panel ?? is it beacause it desapeared ?

[Eagle Eye]

are you using buffered gel card with enzyme treated cells? Plesae report this to your manufacturere.....Are you in US?

We have seen same with some of our patient and it is very scary!!!

[newBB]

are you using buffered gel card with enzyme treated cells? Plesae report this to your manufacturere.....Are you in US?

We have seen same with some of our patient and it is very scary!!!

i dont think is from the gel card , cause other anti jkb is detectable in gel card but only the NEQAS sample is not showling in enzyme ?

[Malcolm Needs ☆]

Hi newBB,

The lack of reactions in the enzyme technique is more to do with the anti-Jkb that is issued in the exercise than your technique.

The samples issued from NEQAS are from patients, but they go through a whole lot of manipulation prio to issue in the exercises.

Just one of these is filtering to get rid of any bacteria, but there is much more to it than that, and, very often, NEQAS antibodies that you would expect to react with enzyme treated red cells, do not.

One of my friends is Jenny White, who works for NEQAS, and is a member of BloodBankTalk, but who does not oftewn get on to the site.

I will email her to tell her to look at this thread, and ask her to give a definitive answer as to why this is so.

:D:D:D:D

[newBB]

Hi newBB,

The lack of reactions in the enzyme technique is more to do with the anti-Jkb that is issued in the exercise than your technique.

The samples issued from NEQAS are from patients, but they go through a whole lot of manipulation prio to issue in the exercises.

Just one of these is filtering to get rid of any bacteria, but there is much more to it than that, and, very often, NEQAS antibodies that you would expect to react with enzyme treated red cells, do not.

One of my friends is Jenny White, who works for NEQAS, and is a member of BloodBankTalk, but who does not oftewn get on to the site.

I will email her to tell her to look at this thread, and ask her to give a definitive answer as to why this is so.

:D:D:D:D

Thanks Malcom i will waite for the answer . i thought about alot. i missed the right answer because of enzyme reaction .

[Eagle Eye]

manufacturer's response: if you have and antibody which needs IgG to react will not be detected by using buffered gel card and enzyme panel.

[newBB]

manufacturer's response: if you have and antibody which needs IgG to react will not be detected by using buffered gel card and enzyme panel.

Thanks for this information !

[jenny white]

Hi,

Malcolm has alerted me to the query regarding the UK NEQAS samples. Whilst the last thing we intend to do at UK NEQAS is to trick and confuse our participants, I acknowledge that there are some issues with distributing diluted antibodies for identification.

The premise of EQA requires that all participants test the same material, and this means we have to produce a 2 to 3 litre pool for each EQA sample. Therefore, we have no choice but to use diluted antibodies, and in some cases the enzyme activity can be lost at a lower dilution than the IAT activity. This is a limitation of the UK NEQAS exercises, but the alternative is to only be able to use a severely limited range of specificities.

I agree that you would expect Kidd antibodies to react in a reliable 2-stage enzyme technique. However, I would not be prepared to exclude Kidd antibodies due to lack of a reaction in an enzyme technique, and especially not where the reactions by IAT indicate that they might be present.

The EQA samples are tested by all IAT technologies in common use in the UK (Tube, DiaMed, BioVue and Capture), and are not scored if not identifiable by IAT at the closing date of the exercise. We are careful not to distribute Kidd antibodies that don’t react well in enzyme in combination with an antibody non-reactive by enzyme e.g. Fya, as this is the situation where the lack of reactivity of the Kidd antibody by enzyme is most likely to increase the degree of difficulty of identification.

As part of the educational aspect of the exercises we advise the use of an ‘enzyme IAT’ to confirm the presence of a weak Kidd antibody (that maybe reacting only with apparent homozygous cells), or to make an exclusion in the presence of other specificities. Enzyme IAT should enhance the reactions with antigen positive cells in real and EQA samples.

So Malcolm is right - it is probably more to do with this particular EQA sample than with the enzyme technique.

[newBB]

Hi,

Malcolm has alerted me to the query regarding the UK NEQAS samples. Whilst the last thing we intend to do at UK NEQAS is to trick and confuse our participants, I acknowledge that there are some issues with distributing diluted antibodies for identification.

The premise of EQA requires that all participants test the same material, and this means we have to produce a 2 to 3 litre pool for each EQA sample. Therefore, we have no choice but to use diluted antibodies, and in some cases the enzyme activity can be lost at a lower dilution than the IAT activity. This is a limitation of the UK NEQAS exercises, but the alternative is to only be able to use a severely limited range of specificities.

I agree that you would expect Kidd antibodies to react in a reliable 2-stage enzyme technique. However, I would not be prepared to exclude Kidd antibodies due to lack of a reaction in an enzyme technique, and especially not where the reactions by IAT indicate that they might be present.

The EQA samples are tested by all IAT technologies in common use in the UK (Tube, DiaMed, BioVue and Capture), and are not scored if not identifiable by IAT at the closing date of the exercise. We are careful not to distribute Kidd antibodies that don’t react well in enzyme in combination with an antibody non-reactive by enzyme e.g. Fya, as this is the situation where the lack of reactivity of the Kidd antibody by enzyme is most likely to increase the degree of difficulty of identification.

As part of the educational aspect of the exercises we advise the use of an ‘enzyme IAT’ to confirm the presence of a weak Kidd antibody (that maybe reacting only with apparent homozygous cells), or to make an exclusion in the presence of other specificities. Enzyme IAT should enhance the reactions with antigen positive cells in real and EQA samples.

So Malcolm is right - it is probably more to do with this particular EQA sample than with the enzyme technique.

Thanks Jenny for detail answer . Thanks to Maclom too !!