Cw reactivity

[RichU]

Hi all,

I am happy to use a negative enzyme result to exclude Rh antibodies. However, I have a nagging doubt about being able to do this with anti-Cw but can't find any reference to this.

Have I made this up or can anyone point me to where I can find this in black and white.

Cheers,

Rich

[Malcolm Needs ☆]

ALL Rh antibodies react with red cells treated with proteolytic enzymes, such as ficin, papain, trypsin and alpha-chymotrypsin (well, red cells that are expressing the cognate antigen, anyway), BUT, be careful because most monoclonal grouping reagents, including monoclonal anti-C^w, will often say to be used by either direct agglutination or by IAT, BUT NOT to be used with enzyme-treated red cells, because they can cause false positives.

Most of what I have written above can be found in Reid ME, Lomas-Francis C, Olsson ML.  The Blood Group Antigen FactsBook.  3^rd edn, 2012. Academic Press.  ISBN: 978-0-12-415849-8.  The rest can be found in the manufacturer's insert, if the reagent is commercial.

Hope that helps, but feel free to get back if it doesn't.

[RichU]

Thanks for your speedy reply Malcolm.

To clarify - If a R1wR1 cell is positive by IAT in the screen/panel but negative against (the same) enzyme treated cells, can I exclude Anti-D, anti-C, anti-e and anti-Cw?

Regards,

Rich

 

[Malcolm Needs ☆]

Hi Rich,

Yes you can, and, don't forget, under BSH Guidelines, you do not have to give blood that has been tested for the C^w antigen, if the unit is compatible by IAT with the patient's plasma/serum.  It is one of the few Rh antigens that can be given under these circumstances.

Be aware though, that I answer this in the knowledge that you are working in the Isle of Man (i.e. the UK).  This may not apply in other parts of the world (particularly Lithuania and Finland).

Edited April 25 by Malcolm Needs
I forgot to put in the last bit!!!!!!!!