this is a donor blood grouping also with tube tech anti A given Neg reaction !!! what could be the reason?

Edited September 17, 2024Sep 17 by yayani

It looks like an A subgroup B to me.  The apparent reaction with the A cells and the donor's plasma in the reverse group in the first photograph could be a weak anti-A1, but more likely it is another specificity altogether (such as an anti-P1).

Without a doubt, however, a sample from the donor should be sent to a Reference Laboratory to have the ABO type sorted out (e.g. by adsorption and elution tests, preferably using a strong human-derived polyclonal anti-A).

Nice crisp photographs, by the way.

"Nice crisp photographs, by the way." thanks 

thanks for advice 

Came to say the same thing as @Malcolm Needs 

We actually just had a patient a week or so ago with a long standing history of being B.....and then all of a sudden we had weak reactions in gel with the anti-A and Anti-A1 in the plasma......

Sent it for ABO genotyping and they were indeed (A)B !

pretty cool stuff - this Blood Banking! 

Edited September 18, 2024Sep 18 by Bet'naSBB

7 minutes ago, Bet'naSBB said:

anti-A and Anti-A1 in the plasma......

actually - that should have said anti-A1 in the eluate.......

we did some adsorption and elution studies "off the books" as that's not in our SOP - but it worked!