Blood_Banker

Thanks. Finally found a great journal article about this phenomena - just takes googling the right keywords to find something. Here is a link for those interested. https://onlinelibrary.wiley.com/doi/full/10.1111/vox.12909

There is a donor that reacts with two polyclonal anti-s antisera from 2 different manufacturers but not a monoclonal anti-s (contains clone P3BER). Is this likely to be an s antigen variant? Quite sure that the donor was genotyped as s positive which is the only reason we tested with polyclonal antisera after we got a negative result with the monoclonal anti-s. Donor is Mi(a+). Anybody seen anything similar? Thanks in advance.

If you spin a sample for 20 secs at 500g, is this the equivalent of spinning a sample for 10 secs at 1000g? We typically use 500g and 1000g on our centrifuges but the new cell washer we have purchased has a high and low speed. The low speed is lower than 500g and the high speed is higher than 1000g. I guess im trying to understand if I can somehow calculate how long I spin at the speeds of the new cell washer that will be equivalent for spinning at 500g and 1000g for different times.

I'm looking to see if anybody knows any suppliers of glass tiles/ceramic tiles for blood grouping that can be washed and reused. We have some old glass tiles that the partitioning has fallen apart so that the reaction mixtures in different wells combine and therefore have to replace them. While I can find disposable plastic tiles easily enough, I'm really looking to replace with preferably glass tiles but ceramic tiles will also be good.

Call it destiny Malcolm, I actually contacted them yeserday after reading some journal articles and they had an advertisement at the end of the articles. Cheers.

Looking for a source of this rare antisera - anybody know any sellers?

Yes in my investigations, I have also found these guidelines but thank you for the link. And your point is absolutely right about the number of lows known to exist - how long is a piece of string. I mean in our particular procedure it even says to test against SARA, which is just crazy considering that there are only a handful of people that have this low incidence antigen. That's why the more I think about it, the more I'm inclined to think that someone just selected some random low incidence antigens to throw in the procedure. But with the crazy amount of regulation in our company now, to modify this procedure is extremely difficult as you have to confront a panel of 10 control members (most of which lack any sort of blood banking knowledge) and have one moron disagree with you to get your change thrown out and have to restart you justification.

I've already tried to go down this path but the current procedure appears to have been so truncated that the references that may have existed have been removed. Now it would be great if I could go to the very first edition of the procedure but our archiving procedures then were very poor so it will take a lot of work to find this edition. I was hoping people might have some answers for me here - also there are a lot of people here who use these reagents so I was hoping to get a general feel for what is expected from these reagents. Also some of my questions are more broader such that people with long experience in blood banking would be able to answer (something that I sadly lack). In particular, whether 2 stage IAT papain testing would help detect relevant contaminating antibodies that simple IAT testing otherwise wouldn't. That is why I'm curious to know if any people use phenotyping reagents to test papainised cells or even if people test their QC reagents with papainised cells (even though IFU don't indicate that these reagents should be used this way!). If the answer is no, then really there is no point in using papainised cells for testing these reagents.

Hi all I'm hoping someone can help answer several questions that I have about the manufacture of phenotyping reagents. Currently our procedures require us to test raw plasma donations containing alloantibodies for antibodies to low incidence antigens. These raw donations are then used to manufacture phenotyping reagents. So my question revolves around whether this procedure is worthwhile. I've been trying to find a reference that specifically states what low incidence antigens should be tested to see if this procedure has some sort of basis in order to eliminate it or modify it. The UK BTS lists the following: "Where appropriate, the following requirements should also be included in performance evaluation:In the case of polyclonal antibodies, contaminating antibodies to antigens having a prevalence of greater than 99% in the general population of the UK should be excluded by negative results in tests using samples of red cells from four different individuals who lack the antigen corresponding to the antibody specificity under test. Tests for the presence of contaminating ABO antibodies should be performed with red cells from a minimum of two individuals of group A1 and two of group B who lack the antigen corresponding to the antibody specificity under test.If tests using all methods recommended for use by the manufacturer do not exclude the presence of antibodies to the following antigens, these antibody specificities should be stated in the package insert as not having been excluded in specificity testing:Xga; Doa; Yta; Cob; Wra; and Vw" The strange thing is that our procedure specifically states to test against Bg(a+) cells specifically but where on earth did this come from. And it presents plenty of problems as we lack Bga antisera to even consider being able to easily perform this test. Secondly as part of this testing we also perform testing against papainised cells but immediate spin testing. Is this really relevant? Are phenotyping reagents used against papainised cells? Are we likey to be able to detect relevant contaminating antibodies if we extend this to a 2 stage IAT with papainised cells? Or are we likely to find all relevant contaminating antibodies using a simple IAT with no enzymatically treated cells. I guess that leads me to my next question - has anybody ever had their polyclonal antisera react to a low incidence antigen? Plenty of questions but I see there are plenty of great minds who can hopefully provide me with some sort of answers to my post.

Hi all We have a sample that contains an enzyme only antibody. We're not interested in identifying it but rather just seeing if we can remove it easily. This enzyme only antibody reacts with all our cells in an 11 cell panel. So if we want to remove this enzyme only antibody do we have to absorb against papainised cells or can we remove it with normal cells. Thanks in advance.

Just another newbie from Australia. Used to work in a core pathology lab in Australia but moved into producing blood transfusion testing products a few years ago. So sorry in advance if I try to promote our fantastic and fabulous products lol.

Has anybody seen any good videos on the Net demonstrating the "Tip & Roll" Technique? Link please! Thx in advance.