About anti-D test in pregnant women

[Yanxia]

I have several question about this topic. I wish I can get help at here. Thanks in advance！

How to quantitate the anti-D antibody?

Does it need D positive RBC?

And how to eliminate the antigen intensity difference?

Some paper says testing the same sample in different laboratory will have a big differentia,so we prefer to use a new method . Does the notation of"iu/ml " can resolve the differentia between laboratory?

[Mabel Adams]

Correct me if I am wrong, but I think you are suggesting that we find a new method for doing titrations of anti-D that removes the variable of varying antigen strength on the different D positive cells used for titrating. I think you are proposing some sort of measurement of D antigen strength on the test cells defined in iu/ml. If this exists already I am not aware of it, but there are lots of things I am unaware of (just ask my teen-age daughter!).

We always use R2R2 cells from our current panel or screen lot. Thus, we usually use different cells every month as we follow a titer. We don't see much lack of consistency, but maybe someone that does more than 1 or 2 titer series per year could provide better data. I know of recommendations that the same cells be preserved (frozen?) and used each time.

What is probably needed is a whole new way to quantitate anti-D, maybe using flow cytometry or something.