Rh IG contain anti-G?

[Rh-fan]

Hmmmmmmmmm, I not sure I agree with that one Peter. If that had been "standard", we would still be calling anti-LW, anti-D and may never have discovered anti-G! The fact is that they are directed against different antigens and this should be reflected in what they are called.

The reaction patern of anti LW is different from anti D, atleasth the strong versions of anti LW.

I am not sure it are different antigens, dispite the ISBT naming in which they are statet as different epitope. With the DNA info of these days, you can see the G antigen as an epitope of the RhD antigen (one of the many) that is also expressed on the RhCE protein if C is present.

But I agree with you that I have to be clear in my nomenclature. What I menth to say was that when a anti G is present (with or without an anti D) it will look as anti C + D. So if there is anti G present in an anti D Ig, it can look like an anti C + D in the serum.

When a donor has before immunisation no anti C and after immunisation with C neg (D+) cells made an anti C (as it look like in the panel) we name it an anti G (+D). We do this even when we have not performed absorption/elution test to prove the presence of anti G and the absence of anti C.

[Rh-fan]

The other thing is, of course, that the first anti-G to be recognised, reacted with an r"r red cell (C negative) that just happened to be a very rare example that expressed the G antigen.

I was not aware of this situation. I thought that the existance ot the G antigen was found when someone had made anti D (+C) after immunisation with D-C+ blood or someone who had made anti C (+D) after immunisation with C-D+ blood. But I belive you.

[Malcolm Needs ☆]

[ATTACH]604[/ATTACH]

I don't know if this will help. It is something that I put together about 4 years ago for my Department for their Continuing Professional Development.

[lacs]

[ATTACH]604[/ATTACH]

I don't know if this will help. It is something that I put together about 4 years ago for my Department for their Continuing Professional Development.

Since we're on the same subject.

We just had a female patient (much older than a typical childbearing age) who has anti-D and C in her plasma but we were able to dilute anti-D and C in eluate as well. We ruled out passive antibodies. Is it a stretch to think the she received rG at some point and attaching to rG cells from current transfusion? This is still a rare situation. It's almost always an academic interest for us so we hardly work up samples like this, unless there is a good reason to do so, due to costs. What else could it be?

Edited February 17, 2012 by lacs

[cbaldwin]

Unfortunately nor Pony. If only it were that simple!

Until fairly recently, if the mutation resulted in a change to an amino acid residue either in the cytoplasm of the cell or was in the transmembraneous part of the Rh molecule, but not any change to the extra cellular amino acid residues, we (in the Reference Service) tended to call it a Weak D. If the amino acid residue alteration was in the extracellular part of the Rh polypeptide, we would call it a Partial D. This, however, did not take into account the fact that amino acid residue alterations in the cytoplasmic or transmembraneous part of the Rh polypeptide can drastically alter the tertiary structure of the molecule, including that part of the molecule that is extracellular.

It is partly because of this that I agree that any RHD gene that is different from the wild-type should be called a variant.

All that having been said though, very many individuals within the hospital community (and some in the Reference community, to be fair), seem to use the terms Weak D, Partial D, D variant and Du interchangably (if that is how it is spelt!), and this becomes immensely confusing as one person talking to another, about exactly the same mutation, may be totally at odds with one another, and not undertsand for a long time that they are talking about exactly the same thing!

The first ever thread I started on this site was about the use of correct nomenclature. It bombed!!!!!!!!!!!!!!!!!!!

I have yet to be in a conversation regarding mutations to RHD or RHCE, but I am preparing myself to be understood.

Malcolm, here is someone who agrees with your opinion!

From page 210, "Human Blood Groups", 2nd edition, 2007,Geoff Daniels:

"Weak D red cells are considered to have all epitopes of D, expressed weakly. Partial D red cells have some epitopes missing, the remainder being expressed normally. Partial weak D cells have some epitopes missing, the remainder being expressed weakly. These divisions, however, are often not distinct and are difficult to differentiate, although the ability to make alloanti-D in partial D phenotypes, but not in weak D phenotypes, is probably the most suitable definition if one is required. However, some individuals with red cell phenotypes initially regarded to be weak D have produced alloanti-D. Weak D is often associated with RHD mutations encoding amino acid substitutions in the cytoplasmic or membrane-spanning domains of the D protein, whereas partial D is usually caused by changes in the extracellular loops. However, this is not absolute and is dependent, to some extent, on the model for the conformation of the Rh proteins in the membrane used. The terms "weak D" and "partial D" are retained here to assist in providing some degree of order to the large number of aberrant D antigens, but there is a compelling argument in favour of scrapping the terms and replacing them with "D variant".

[galvania]

I agree too and have been pushing this terminology (D variants for all) for years:)