Ortho 0.8% screen cells VS676 exp 11/12/13 false pos?

[Mabel Adams]

We opened this lot of screen cells on 10/14 and have had 6 patients react weakly with cell 2 but found nothing in gel panels or PEG 3-cell screens. Of course many patients are negative with it.  We have similar results in 3 sets of vials--2 open for 2 weeks and one freshly opened.  If anyone else is having similar results please notify Ortho so they get enough data to make a determination on this donor's suitability for screen cells or whatever else is wrong.  The cell is not listed as Bg positive but they test their donors only once I have heard.

[Justina]

Good to know, cell 2 is looking a bit funky.

[David Saikin]

Are the pts reacting mutliparous women?  Most of mine have been.  I have found that the "junky" cell 2 rxs are probably something and have discussed this with ortho several times.  I have found that enzyme pretreatment removes the rxs about 80% of the time. The other 20% - only the R2R2 cells react and the pt is invariably E negative. 

[Malcolm Needs ☆]

Are the pts reacting mutliparous women?  Most of mine have been.  I have found that the "junky" cell 2 rxs are probably something and have discussed this with ortho several times.  I have found that enzyme pretreatment removes the rxs about 80% of the time. The other 20% - only the R2R2 cells react and the pt is invariably E negative. 

Edited November 1, 2013 by Malcolm Needs

[Malcolm Needs ☆]

Despite the fact that they say their cells are Bg negative, and because of what David says, it may still be worthwhile treating the cells with chloroquine diphosphate to see if the reactions disappear; Bg antigen expression can vary very greatly in the same donor from one time to another.

[JoyG]

We reported this phenomena to Ortho on 9/24/13.  They asked us to perform a DAT_IgG on this cell and it was positive!  We removed the cell (actually the panel) from use.

[Mabel Adams]

I assume the DAT is negative on the screen cell since it doesn't react with all patients but I didn't test it.

[Justina]

I assume the DAT is negative on the screen cell since it doesn't react with all patients but I didn't test it.

The DAT is negative on that cell (we tested it yesterday).