Isohemagglutinin titers

[alt5575]

Hi,

 

I am writing an standard operating procedure on performing isohemagglutinin titers on apheresis group O platelets.  I am having troubles finding information on this subject that agrees with each other.  It appears that the procedure varies from tittering and testing at immediate spin in one place to tittering and incubating at room temperature for 30-60 minutes.  I have also found a procedure where the titer is incubated at 37 degrees C for 30 minutes.  I would love to hear what other facilities are using for a procedure.  I am also having troubles finding a cutoff value.  One I have read says the cutoff is 200, the next I read says the cutoff ranges from 128 to 250. I would also like to hear what other facilities are using as a cutoff.

 

Thanks.

[Eagle Eye]

Tesing a RT for 15 minutes and cutoff is 1:64