I typed a unit of RBC with different sources of anti sera and the following are the results. 

1) Ortho monoclonal Anti-Jka (manufacture insert says incubate at room temp 5min to 30 min and read macro) 

at 5' incubation- 0 

at 15' incubation- w 

repeated result at 5 min incubation - 0 

at 15 min incubation - +/- or micro (even though insert says to read macro, I read micro because it seems "grainy" on the mirror) 

 

2) Immunocor IAT reagent types negative 

 

3) Unit will be typed with Bio Rad Monoclonal reagent today but I think I am going to type negative with this reagent since it react weaker. 

 

My question- is this unit Jka neg, Jka pos or maybe Jka variant? As Ortho reagent is monoclonal, should I be expecting other specificities in this antisera bottle? I learned that monoclonal reagent are very specific? 

Above all, is it safe to give this unit to patient with Anti-Jka? 

 

Thanks in advance for your replies. 

I typed a unit of RBC with different sources of anti sera and the following are the results. 

1) Ortho monoclonal Anti-Jka (manufacture insert says incubate at room temp 5min to 30 min and read macro) 

at 5' incubation- 0 

at 15' incubation- w 

repeated result at 5 min incubation - 0 

at 15 min incubation - +/- or micro (even though insert says to read macro, I read micro because it seems "grainy" on the mirror) 

 

2) Immunocor IAT reagent types negative 

 

3) Unit will be typed with Bio Rad Monoclonal reagent today but I think I am going to type negative with this reagent since it react weaker. 

 

My question- is this unit Jka neg, Jka pos or maybe Jka variant? As Ortho reagent is monoclonal, should I be expecting other specificities in this antisera bottle? I learned that monoclonal reagent are very specific? 

Above all, is it safe to give this unit to patient with Anti-Jka? 

 

Thanks in advance for your replies. 

 

dothandar, you are absolutely correct in saying that are known Jk^a variant antigens.

 

Under the circumstances, DO NOT give this unit to a patient with anti-Jk^a!  It is easy enough to find another Jk(a-) unit, without taking the risk.

 

I am going to attach (I hope!!!!!!!!!) a lecture I have recently written on the Kidd Blood Group System, which may explain why, BUT, be warned, I have yet to check this lecture for complete accuracy, so treat it cautiously.

 

In Depth Lecture on The Kidd Blood Group System.ppt

I do not have much knowledge about these variants. Thank you very much for the lecture slide and helpful advice. I am hesitating  very much to enter this unit as Jka-, though this donor has been typed as Jk(a-) three times since 2011. Thank you very much for the assurance.  

 

P.S. Love slide number 38 

Edited August 25, 20159 yr by dothandar

Ah, slide 38 is an almost, but not quite, direct quote from Jill Storry.

Yesterday, I found out from a senior tech that weak positive (rough reaction) were often found with this Ortho Monoclonal reagent (I will look up the clone number when I get to work today). in 1995 (way before I started working in this lab) when molecular genotyping was being validated here, most of these units that has weak reaction are Jk(a-) molecular typing and variant Jka was not found when sequencing was done. 

 

Anybody else having these "rough" reactions with Ortho Monoclonal Anti-Jka? Should I stay away from this reagent when performing donor typing? Or should I keep using this reagent to type donors and avoid labeling units with "rough" reaction as Jk(a-)? Any thought? 

Edited August 26, 20159 yr by dothandar

We've been using it for quite a while, no weak/rough reactions come to mind..

I have found that the monoclonal Kidd typing sera available (from a few vendors) seems to give weaker rxs than I am comfortable with. 

Unfortunately our lab switched our Anti-Jka reagent that it is no longer available for me to play with