We use 0.8% Ortho screening cells for our gel method but over the last few months have noticed that the screening cells are degrading faster. They are out, in use, most of the day and on off shifts are kept in the refrigerator except when in use. There is apparently no other maker for 0.8% screening cells so does anyone have any suggestions about how to stop this degradation? We will probably have to start pouring off aliquots for daily use. No we will not be making up 0.8% from a 3-4% screening cells, sorry too many contamination issues.

We have been using Ortho gel cells for a few years now and occasionally have problems with them. What does Ortho say? If they sent out a bad lot they will have had other complaints.

Of course they say they have had no complaints. I know this is not true do to the ongoing dialog among the other blood bank supervisors in the VA system.

We made our 0.8% cells from 3-4% cells for several years with no contamination problems, though it was a serious pain in the...... That's the only way we could get around the problem of funky reactions.

We still make ours up daily from a 3-4% suspension. The pain in the .... is outweighed by the avoidance of the issues that started this thread. An added bonus is reduced contamination for our lab. If you are into your primary bottle frequently was when we experienced higher contamination frequency. You have to do what works for your situation. Sounds like you need to do some looking for light protection and keeping the bottles cooler. I think Wescott Lab Solutions offers a sort of sleeve to help with the light exposure issue (they advertise on the site here) Give them a call and see if they have some suggestions for you. The company owner is a past blood banker (is there such a thing??) and knows his products.

We aliquot from the bottle daily and keep the aliquots in an opaque plastic container when out on the bench to keep away from the light. We haven't had as many contamination problems since we started doing this.

A question for those who dilute the 3-4% cells. Did you do any kind of validation?

A question for those who dilute the 3-4% cells. Did you do any kind of validation?

Yes. We diluted Immucor cells with Ortho's diluent. We simply ran duplicate ABS with Ortho cells and our diluted cells - about 40 negative screens and 10 positive screens as I recall. That's how we validated gel to begin with, so I just repeated that plan.

It could probably be easily solved by keeping the reagents in the fridge more. We keep ours (though not ortho) in the fridge unless they are actually being opened for use. They go back in the fridge immediately after - not after the antibody screen is finished...

Edit - the expiry quoted is based on the reagents being kept in the fridge. If they are out during the day then you will expect degredation.

We are a small facility and alternate sets of screening cells from one day to the next. I also only use one set for 2 weeks. At that point I open new sets of the same lot. This has helped in addition to keeping the reagent rack in a black file box to protect it from the light.

We try to use up open vials up as quickly as possible and put an in use expiry date of 6 days on them , if not used up by end of 6 days we bin them

as we focus on using up opened vials rather than opening up a second set of vials we don't usually have a problem

we use Diamed cells

Have used both ortho and Diamed cards / cells over the last 20 years and I know which one I prefer - Diamed

Grief! 7 days?

Our cells have a 28 day expiry on and show no loss of reactivity during that time. We used to use Diamed to the same effect but now use a donor-centre's own cells as they are much cheaper.

Each of our 4 workstations has fresh aliquots of the screening cells each day. The original containers are kept in the fridge. This works well with no degradation or contamination problems.

We rotate three sets of the 0.8 screening cells; one set for each shift. From your post it sounds like you are using one set 24/7.

Have you considered rotating two sets, one for day use and one to be use on the off shifts. The set used on the off-shifts would be refrigerated when not in use.

A question for those who dilute the 3-4% cells. Did you do any kind of validation?

Like AMcCord we use Ortho's diluent. I have validated Immucor's cells in the past and am in the process of doing the same with Biorad's red cell reagents as we speak.

We use 0.8% Ortho screening cells for our gel method but over the last few months have noticed that the screening cells are degrading faster. They are out, in use, most of the day and on off shifts are kept in the refrigerator except when in use. There is apparently no other maker for 0.8% screening cells so does anyone have any suggestions about how to stop this degradation? We will probably have to start pouring off aliquots for daily use. No we will not be making up 0.8% from a 3-4% screening cells, sorry too many contamination issues.

We keep cells on 2 racks: 1 for day shift (6:30 am- 7 pm) & one for evening & nights. We alternate daily QC between the racks. 2nd rack is used less so is refrigerated more. Stored in refrigerator without internal lights.