Anyone familiar or have heard of HU5F9-G4: anti-CD47 (mostly looking at the European readers as you all get approval for drugs earlier than we do in the US)?  It is in phase 1 clinical trials and I believe it is being used for treatment of AML and solid tumors.

And what part of the Red cell does this cross-react with?  Anything like DARA?

Let me preface by saying we haven't seen this in my lab yet.

From what I've been able to scrape up here and there, anti-CD47 binds to CD47 on cell membranes and blocks the "don't-eat-me" signal allowing macrophages to destroy the cells.  Cancer cells apparently express high numbers of CD-47.  They are in phase I clinical trials for treatment of AML.

In testing all panel cells react 4+ at RT to 2+s at Anti-IgG.  The RT reactivity is also seen in the reverse type. Further testing looked as if papain treated RBCs absorbed the reactivity.

Hopefully, we'll see something in the literature soon or I'll see it in my lab and we can "play around" with it.  Not sure if that is a good wish or a bad one...  

11 hours ago, dragonlady97213 said:

In testing all panel cells react 4+ at RT to 2+s at Anti-IgG.  The RT reactivity is also seen in the reverse type. Further testing looked as if papain treated RBCs absorbed the reactivity.

IgM, IgG or both ?

Edited March 16, 20178 yr by exlimey

From what I've read, the antibody uses an IgG4 backbone.  Using Immucor's GammaClone that doesn't pick up IgG4 alloantibodies should work, but I haven't seen anything verifying that.

11 hours ago, dragonlady97213 said:

From what I've read, the antibody uses an IgG4 backbone.  Using Immucor's GammaClone that doesn't pick up IgG4 alloantibodies should work, but I haven't seen anything verifying that.

Apologies, I now remember you posted that earlier. The mind is a terrible.....wait, what was I saying..........

It's IgG4 nature and use of the Immucor/Gamma reagent won't help much if it's causing direct agglutination before the antiglobulin phase, especially in reverse typing.

Here's a little something I found useful:

http://nybloodcenter.org/media/filer_public/2017/10/04/2017aabbpostervelliquetteserological_observationsfinalcp246.pdf

For screens, I would avoid any phase except the IAT one to minimize the carryover.  Our facility hasn't started any trials of this drug yet, so I haven't had a chance to try this (or try using gel in a neutral card with Immucor Gammaclone IgG).  My suspicion is that gel won't work, but I still want to give it a shot.

I just saw that the FDA approved the use of Keytruda (anti-CD47) for a type of lymphoma so wondered if anyone has newer information for managing these patients if they need transfusion.  Does the Immucor AHG work reliably?  How are you resolving typing discrepancies?

20 hours ago, Mabel Adams said:

I just saw that the FDA approved the use of Keytruda (anti-CD47) 

Everything I am reading on that one says it targets PD-1, which doesn't look like it's expressed on red cells (obviously, I could be wrong - this is the result of a couple Google searches, I haven't opened my actual immunology book in a while!), so hopefully this one won't interfere with our testing.

My mistake.  Keytruda is not the name of the anti-CD47 drug.  Does it have any name besides anti-CD47 or HU5F9-G4?  Is it still in clinical trials in the US?

I think I've seen it called CAMELLIA. 

Looked up CAMELLIA and it comes up on the ClinicalTrials.gov website as anti-CD47 and used for AML and MDS. Sponsor is company called Forty Seven Inc. and is currently in Phase 1 trials expecting to end August 2018.