All DR reactivity by Luminex https://www.ashi-hla.org/forums/posts.aspx?topic=1374701 Sat, 6 Jun 2026 11:42:17 GMT Tue, 8 Aug 2017 21:35:27 GMT Copyright © 2017 American Society for Histocompatibility and Immunogenetics All DR reactivity by Luminex https://www.ashi-hla.org/forums/posts.aspx?topic=1374701 https://www.ashi-hla.org/forums/posts.aspx?topic=1374701 Hi all,

We have a patient with reactivity to all DRB1 and DRB3/4/5 antigens (including self-alleles) when tested by Luminex single antigen (One Lambda). We have seen it before, as have many others, but I would like to do a survey about how other labs would handle such a case.

  1. Are there any publications showing the cause of this reactivity or demonstrating its clinical relevance (or lack thereof)?

  2. How would you report these results to clinicians? For example, do you just include all the specificities on a report but don’t call them unacceptable in UNET, or do you include the specificities on the report and add a comment about non-clinically relevant reactivity, or do you not report any specificities?

  3. Is there any kind of serum treatment or assay modification that can get rid of this reactivity, while maintaining any “real” antibody that might be present underneath it?

Thanks very much for your help with this.

Susan

]]> Fri, 28 Jul 2017 21:43:50 GMT https://www.ashi-hla.org/forums/posts.aspx?topic=1374713 https://www.ashi-hla.org/forums/posts.aspx?topic=1374713 4. Does this kind of reactivity eventually go away in future samples from the same patient?
]]> Fri, 28 Jul 2017 22:16:03 GMT https://www.ashi-hla.org/forums/posts.aspx?topic=1375003 https://www.ashi-hla.org/forums/posts.aspx?topic=1375003
We have had some patients like that too. Most often, we find that they don’t truly have antibodies that react with ALL DR, but the Abs do react to most subtypes. If the patient expresses a DRB1*04 subtype, for example, she may react to most of the other DRB1*04 subtypes, but not her own subtype.

When the LSA background is high, I am much more conservative about which reactivities I accept as “real.” Those apparent Abs usually go away in future patient sera when the interfering substances subside.

You did not state the patient’s typing, but as you know, several DRB1 alleles and some DRB1*07 are not associated with DRB3, DRB4, or DRB5. If the patient does not herself express DRB3, DRB4, or DRB5, then Ab to DR51, DR52, and DR53 would not be surprising.

Best wishes,
Charlie
Charles T. Lutz, MD, PhD
Vice Chair for Research, Department of Pathology and Laboratory Medicine
Director, Division of Cell and Molecular Pathology
Professor, Department of Microbiology, Immunology and Molecular Genetics
Member, Markey Cancer Center
University of Kentucky
800 Rose Street, MS 117
Lexington, KY 40536-0298
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“Ignorance more frequently begets confidence than does knowledge” Charles Darwin]]> Mon, 31 Jul 2017 16:01:24 GMT https://www.ashi-hla.org/forums/posts.aspx?topic=1375047 https://www.ashi-hla.org/forums/posts.aspx?topic=1375047
Case: male patient with no previous TX, self = DR11,DR12,DR52. Two samples (6 months apart) by the OLI Labscreen SAB were positive for all DR beads including self, from ~1000-7000MFI. However, OLI FlowPRAs were 0% and squeaky clean. We also tested by the OLI Labscreen-PRA beads which was negative! After a few surrogate XM to be really sure, we reported it as pan-DR.
Responses:
1) I've only found two publication (including a poster) that discuss these odd cases: ASHI poster: CHARACTERIZATION OF PAN-DR ANTIBODIES DETECTED IN TWO TRANSPLANT CANDIDATES. and World J Transplant 2014 September 24; 4(3): 153-167 (i'll email them to you).

2) We reported the SAB as false-positive. We said there was a pan-DR reactivity but that most screens were negative for DR antibody. We did not call any DRs as UAs in UNET.

3) We didn't try any special treatments. We used EDTA-treated sera for SAB.

4) We will see! This patient has been consistently negative for FlowPRAs for 1.5 years, and coming up on another SAB+ Phenotype-PRA beads in a couple of months.

Interestingly, this patient also had reactivity to Cw1/12/15 which we learned was a false reaction pattern (thanks to a talk at ASHI). Therefore, we typed him for Cw, found out he typed as Cw12. Once again FlowPRA and Labscreen-PRA were negative for Class I. Now we don't believe Cw1/12/15 reactivity by SAB!]]> Mon, 31 Jul 2017 18:34:31 GMT https://www.ashi-hla.org/forums/posts.aspx?topic=1376807 https://www.ashi-hla.org/forums/posts.aspx?topic=1376807 We've seen the same in several patients, where all the DR (DRB1 and DRB345) are moderately to strongly positive, including self antigens.

We usually reflex these to phenotype beads/PRA, and report the single antigen negative if the PRA is negative. We've also done surrogate crossmatches on a few of these sera and found them to be completely negative. The most problematic are those that are post-transplant; in these cases, where we are looking for DSA, we might run single antigen on another vendor's platform/beads.

 

I agree with above experience that often the class I single antigen shows reactivity to Cw1, 12 and 15.

 

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