exlimey

This is the best thread, EVER !!!! Keep it rolling, please.

I was originally trained using an "inverted microscope" - that was a thing of beauty. The light source was above, the relatively low-powered lens below. The cells stayed in the tube and the tube could be rotated to get movement and/or a suitable thickness of liquid in which to see the cells. It was great and very easy to use (even though it had a large footprint), but as others have commented, if one looked long enough, one could always find "friendly cells". I'm not a fan of microscopic reading and I dissuade others from doing it. As I've said in the past, high level tools and techniques

Apologies. I was discussing reagents used in tubes, not gel cards.

I disagree. It is in the FDA's manufacturing requirements that DVI be detected. Unfortunately, I couldn't find a suitable CFR quote, but several of the Directions for Use I looked at from different manufacturers indicate that they detect DVI. However, I agree that strategic differential use of reagents such as these on patients vs donors can certainly help the transfusionist and/or determine the necessity for Rh Immune globulin.

Anti-D reagents are specifically formulated to detect DVI - that is REQUIRED by the FDA in the USA. It was also true of the human sera-based reagents I manufactured in the UK during the 1980s. There was a period when anti-D reagents were approved for donors or patients. The reagents used for donors were required to detect DVI, arguably the "weakest" expression of the D antigen of the known D-variant and typically that meant an antiglobulin phase was required. Those reagents formulated for patients often were not designed to detect DVI (had no IAT) and subscribed to the "it's better to tre

See....you've already got the makings of a club. You can celebrate your CEce heterozygosity together.

Good point, but we're very unlikely to make the antibody.

Sorry, John. You'll have to start your own club. Perhaps "f-negatives Rule", or something like that.

An interesting idea, but I'm not sure I want my psychological dirty laundry hung out for the world to see.

I confess: I'm much the same way in the OCD sense. I'm also DCeDCe (R1R1), so perhaps this issue hits a little too close to the sensitive area.

An EXCELLENT question, John, but as Malcolm suggests, is appears that there is still a large dose of "we always do that" in many laboratories.

Short answer: Yes How was the anti-Jka detected initially, i.e., what technique ? Assuming it was an antiglobulin test, but was it Gel, Solid Phase, LISS, PEG ? Yes, the panel cells are now ficin-treated and antibodies to Jka should be enhanced, but the test conditions that were used in the original assay may not exist when ficin-treated cells are used - one may need to add LISS or PEG, one may need to test by Gel or Solid Phase.

Ouch !

Actually, I'm not suggesting that replacement of the batteries is cause to re-qualify a timer. Accuracy of most timers is not affected by battery replacement because there is no actual CALIBRATION, i.e., no adjustment process. Typically, today's timers are CERTIFIED - their accuracy is verified against a standard. That accuracy is independent of the batteries. But, I do agree that a broken/unreadable timer is the ultimate expression of "inaccurate".

Perhaps the real question is: Do you (or the supplier/certifier) actually CALIBRATE them ? That is, can the reading be adjusted in any way ? If the timer differs greatly from the "Standard", can it be tweaked into range ? Most simple electronic (battery-powered) timers are not adjustable. I'm not even sure that the official certifiers (the ones providing the certificates) are able to adjust the cheap and cheerful electronic timers. The electronics are so reliable (and cheap) these days that it's rare to find an inaccurate timer. The ones with unacceptable performance are probably just discarde