PathLabTalk

Register now to gain access to all of our features. Once registered and logged in, you will be able to contribute to this site by submitting your own content or replying to existing content. You'll be able to customize your profile, receive reputation points as a reward for submitting content, while also communicating with other members via your own private inbox, plus much more!

This message will be removed once you have signed in.

jollymon

RESt and DARA

18 posts in this topic



Interesting question - do rabbit red cells carry CD38 ?

I thought I heard/read that removal of anti-CD38 by adsorption was not successful using human cells (which we know carry CD38). Even if rabbit red cells do carry the marker, I assume the same would apply ?

Share this post


Link to post
Share on other sites

We have been  asked by reference lab to provide informmation if patient is on CD38. It will be useful for them to process the sample.  if patient is on DARA how does reference lab process the sample. Do they use different absorption techniques? 

 

Share this post


Link to post
Share on other sites
9 minutes ago, gagpinks said:

We have been  asked by reference lab to provide informmation if patient is on CD38. It will be useful for them to process the sample.  if patient is on DARA how does reference lab process the sample. Do they use different absorption techniques? 

 

Well, in a way, yes.  They will not waste time on trying to perform alloadsorptions (as these don't work) and will probably perform genotyping from the word go, rather than trying to get a phenotype.

To be honest, the submitting hospital should give the Reference Laboratory as much information as they can about ANY patient, whether they be on ANTI-CD38 (gagpinks, they are on a monoclonal antibody - not a monoclonal antigen!!!!!!!!!!!) or not.

Share this post


Link to post
Share on other sites

The only way I'm aware of is DTT treating the screening cells used.  

Ensis01 likes this

Share this post


Link to post
Share on other sites
On 2017-5-27 at 11:05 PM, MaryPDX said:

The only way I'm aware of is DTT treating the screening cells used.  

I agree MaryPDX, but, unless the Reference Laboratory is made aware that the patient has been on Dara, time and reagents can be wasted by trying to sort out the problem by more "traditional" means.

Share this post


Link to post
Share on other sites

I've heard that they can decide it is some weird Lutheran antibody if they don't know it is DARA.

Share this post


Link to post
Share on other sites
4 hours ago, Mabel Adams said:

I've heard that they can decide it is some weird Lutheran antibody if they don't know it is DARA.

I haven't heard of that method Mabel.  What is the "weird" Lutheran antibody.

Share this post


Link to post
Share on other sites

A little off topic but related to DARA:  Some of my techs are reporting that hand-washing the tubes in tube testing (PeG) versus using a cell washer is more likely to give negative reactions with DARA samples.  I wonder if anyone else has experienced this?

Share this post


Link to post
Share on other sites
On 5/30/2017 at 3:26 AM, Malcolm Needs said:

I agree MaryPDX, but, unless the Reference Laboratory is made aware that the patient has been on Dara, time and reagents can be wasted by trying to sort out the problem by more "traditional" means.

I heard last week that there is another method some of the US ref labs are either using or want to start using for the Dara patients and Kell isn't affected, but I can't for the life of me remember what they said and I haven't had any luck with google. 

Has anyone heard anything similar?

Share this post


Link to post
Share on other sites

I haven't heard anything (but then I am retired), but something could come out from the ISBT Meeting taking place in Copenhagen at the moment.  I will get my "spies" on to it!

jmm8427 and MOBB like this

Share this post


Link to post
Share on other sites
9 hours ago, MOBB said:

I heard last week that there is another method some of the US ref labs are either using or want to start using for the Dara patients and Kell isn't affected, but I can't for the life of me remember what they said and I haven't had any luck with google. 

Has anyone heard anything similar?

You may be referring to trypsin-treatment of the red cells (screening cells). Apparently CD38 is destroyed/inactivated (along with Lutheran system determinants) but Kell system antigens remain intact. Other blood group antigens are also affected by trypsin, so I think the modified approach involves testing the patients' samples against both DTT-treated and trypsin-treated cells.

To further complicate matters.....manufacturing a reliable, consistent trypsin reagent is VERY difficult. The enzyme activity of source material varies immensely and, as with other enzymes, stability is a problem.

MOBB, BldBnker, Ensis01 and 2 others like this

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now

  • Advertisement