Quality Control of Panel cells

[PHYLLIS]

How often should Panel cells be QC'd? Should this be done on receipt only or day of use?

[tbostock]

There is no regulatory requirement to QC panel cells that I know of. We just do a visual inspection upon receipt.

[Likewine99]

We are the same as Terri. CAP says screening cells must be QC'd each day of use, which we do.

We don't consider the panel a screen, it is confirmatory testing done to f/u up with the positive screening results.

[David Saikin]

I qc m;y panel cells when they are received using a dilute (1:20 or 1:40) antibody depending on whether they are 3% or 0.8% cells. Check your package insert, if the manufacturer requires qc, you have to do it/CFR. Otherwise, I do no other qc while they are in date. There is some question regarding use of outdated panel cells - I am mulling over qcing those outdated but used with the same weak ab (but I really do not care to waste either gel cards or other reagents on this). I may wait to get citted by someone before going that route.

Edited December 23, 2008 by David Saikin
Check the cfr

[JHH1999]

Performing daily QC of screening cells using a weak antibody is a good idea and necessary.

But, QC of panel cells. This would really seem like a huge task. I would not know were to begin. What antigens do you type for on the panel cells. Are some more liable than others that could indicate deterioration or would you need to test them all. This would use a significant amount of antisera and take a lot of valuable time.

I would suggest panel cells do not need to be QC'd. They are used to determine antibody specificity. If you use multiple cells for rule outs, it would be a low risk. Other things like confirming the patient's red cells are negative for the antibody, typing units for the antigen and the actual crossmatch help prevent problems.

Of course using expiring panel cells has been a bit of a controversy for years.

[Trek Tech]

This baffles me every time this issue comes up. How would you QC a panel? Which antigen would you QC and why? Obviously you could not check every antigen on every cell so what would the point be?

I can understand QC'ing expired cells you might use to rule out with. In that case you would check the antigen that you are checking for with antisera but that does not check the level of sensitivity.

I enjoy reading what others are doing and their rationale for it.

[ckcheng]

I agree panel is not a screen, it is a part of the antibody workup. QC on panel daily, like screen, or right before each workup is not necessary cuz not economical.

However, if you do wanna QC the panel to see if weak antibody still be detected before it expires, use weak reactive anti-Jka and/or anti-Fya against the panel on the first and the last days of use.

Any comments?

CK Cheng, MSc, SBB(ASCP), CQA(ASQ)

Dec 2008

[Lcsmrz]

For QC of panels to be performed, you would need information that only the manufacturer can provide, such as stability of common antigens in their diluent, age- or process-related appearance of cryptantigens, storage issues with the diluent, and the like. Without this kind of information or other guidance from the company, and without published studies in the literature, any QC performed would be a guess (at best!) and without any scientific merit.

We defined "periodic testing" as mentioned in the product insert (IMHO, a CYA ststement!) as required with each use after 30 days. Since we receive our standing order shipment before the 30 days are up, we never have to QC our panels, and inspectors are happy that we have a panel QC procedure in our manual.

Performing QC when using expired panels is a whole other topic ...

[ckcheng]

Resolve Panel from Ortho packing insert says

For quality assurance, RESOLVE Panel should be tested periodically with weak antibodies.

However, 'periodically' and 'weak abs' are not defined. So I suggest to choose weak reactive anti-Jka and anti-Fya to test at least at the last day of the panel to make sure it still works properly before it expired.

Ck Cheng, MSc, SBB(ASCP), CQA(ASQ)

Dec 31, 2008

[ovrwkd]

Get more bang for your buck. Prepare a 1:128 or 1:256dilution of anti-D and test this against your screening cells. This way you won't waste precious and costly Kidd or Duffy antisera.

Once you prove your sample reacts against reagent red cells you've met your requirement for the day. Save your panels!

[ovrwkd]

1:256!

[PHYLLIS]

I QC,d the Ortho Panel cell B with the Ortho confidence serum and got 1+ to +/- reactions in tube.

[ovrwkd]

A weak dilution of anti-D should produce a 2+ reaction when tested with albumin, LISS reagent or PEG. MTS Gel usually yields the same result. Ideally for QC you would have a negative control with your panel to prove reactivity is not due to other issues. I mentiond the previous dilutions as I'm lazy in math and love serial dilutions. Make whatever gives you a 2+ reaction.

I've noted some facilities use a 2-3 cell screen, others have done the whole panel. A representative amount of cells per panel lot should be sufficient to prove you have reactivity.

[PHYLLIS]

I feel that every cells is unique, so I would have to test each cell for reactivity.

We always get a 4+ reaction in gel.

[Malcolm Needs ☆]

Within the Reference Laboratories of the NBS in England, we test the panel each day with an weak anti-D, a weak anti-c, a weak anti-K and a weak anti-Fya. This covers a positive and a negative for each cell.

I should stress that we use genuine weak antibodies, rather than strong antibodies that have been diluted, because the biological dynamics of genuine weak antibodies, such as the equilibrium constants between antibody/antigen complex and antibody and antigen not complexed (and remember, this state is dynamic) is different for weak antibodies and strong antibodies that have been diluted.

[dmpollock]

As far as requirements go, the CLIA Interpretative guidelines state:

There are no daily quality control requirements for reagent red cell

panels used in antibody identification. Panel quality control is a

combination of serological test results, such as: strength of reactions

and patient phenotype; statistical probability, patient’s medical

history; and laboratory standard of practice (i.e., how the laboratory

handles compatibility testing for patients with unexpected antibodies).

However, the QC requirements pertaining to new batch, lot, shipment

of identification systems at §493.1256(e)(1) must be met.

Reference: page 27 of: http://www.cms.hhs.gov/CLIA/downloads/apcsubk2.pdf

[RR1]

Malcolm,

Are the NBS controls we buy (-D, -c,-K,-Fya), diluted or genuine weak ?

Thanks

[Malcolm Needs ☆]

They are genuine Rashmi.

They are exactly the same as we use ourselves ('cept we don't pay for them of course!).

[John C. Staley]

Just thought I would throw in my 2 cents worth. Never QC'd a panel, never considered QCing a panel and can see no need or value in it.

[bxcall1]

I've got 30 years and agree with Staley.

[Malcolm Needs ☆]

Candidly, I agree that the controls are a waste of time! It's just that we have to follow our national SOP!!!!!!!!

35 years, but feels nearer 135 some days (most days though, are wonderful, as my job is my hobby).

[keisterkid]

For giggles we typed our panels with commercially prepared antisera when we received them and for the next 6 months after outdate. The S and Fy antigens became weak to undetectable after 3 months on the Immucor panels while the Ortho and Medion panels maintained their S and Fy antigens for 4+ months. The Rh antigens got stronger in many instances. We are in the process of getting human plasma with the antibodies, diluting to a 2+ reactivity, and repeating the work.

[Nisar]

How often should Panel cells be QC'd? Should this be done on receipt only or day of use?

visual inspection and not expired is enough and there is no need of qc.if you want to use expired panel cells for ruling in or out then you can do Qc for that corresponding antigen.

[teskridge]

Can someone tell me how you QC a 0.8% expired panel cell that you are using on a select panel for rule-outs?

[Malcolm Needs ☆]

The way we do it is to test the cells with specific grouping antisera, but we have all sorts of grouping reagents available to us, which, I appreciate, most laboratories do not.