We have an OB patient with an anti-E. This morning when I titered it, it gave me some very odd reactions, something I have never seen an antibody do before. The repeat was the same.

I performed the titer in gel.

The first (raw) tube was weak, the second tube was 1+ and the third tube was a strong 2+, the rest were negative.

I repeated it thinking I set up the tubes incorrectly. The repeat was the exact same with tube 4 being weakly positive. The rest were negative.

Anybody else ever see anything like this? And what's up with the antibody that would cause this?

Thanks in advance for any and all responses.

Melissa

You used to hear about prozone but I don't know if you see it in gel and I think the titer would be much higher than that.

You CAN see prozone in gel - but yes, usually it is with stronger antibodies. I have never seen one before at this titre (DiaMed gel - can't speak for the others)

Why don't you try your titer in tubes (based on your results I would bet that you find no reactivity). . . were you using Ortho cells? I'd try a different vendor's cells and see what you get. I have had R2R2 Ortho cells react in gel but no other vendor's R2R2 would react unless enzyme pretreated.

Thanks for all your replies! Right after I posted this - my brain did the old "Of course - prozone!"

I thought I would titer it in the tube next - just to see what it does.

I, too, was very surprised it wasn't a higher titer than that.

We'll see what happens as the pregnancy progresses.

Thanks again!

I wonder if this is a new Anti E and the concentrations of IgM and IgG fractions are somehow involved in these reactions.

I wonder if this is a new Anti E and the concentrations of IgM and IgG fractions are somehow involved in these reactions.

I was going to suggest this as well, we had a patient with a persistent IgM anti-E that never seroconverted to IgG.