SSP new format study

Olerup SSP

IMPROVING RESULTS IN SSP LOW RESOLUTION TYPING

Olerup SSP® Low resolution Kits – Flexibility and Convenience

• A comparative study of different kit formats for: – HLA-A – HLA-B – HLA–DRB

• Objective: – To investigate the frequencies of typing ambiguities for low resolution SSP typings in two sets of samples – To compare the performance of the ”classic” formats to the new formats.

• Material and Methods – 102 randomly selected Swedish blood donors – 102 consecutive UCLA Exchange DNAs – The most current lots of the Olerup SSP® kits for HLA-A, -B and -DRB low resolution typing • ”classic” format vs new, extended formats

– Analyzed using Olerup SSP ® version of Helmberg-SCORE™ , allele database 3.5.0

Product formats vs Low Resolution Ambiguities, All samples 40%

35%

30%

25%

20%

) g(% b m a tin slu re w Lo

15%

10%

5%

0%

HLA-A

HLA-B

HLA-DRB

All samples, "classic format"

14%

16%

3,4%

All samples, new format

0,5%

1,5%

0,0%

Product formats vs Low Resolution Ambiguities, Sample Breakdown

HLA-A

HLA-B

HLA-DRB

”Classic” format

New format

”Classic” format

New format

”Classic” format

New format

All samples (n=204)

14%

0,5%

16%

1,5%

3,4%

0,0%

Random samples (n=102)

16%

1,0%

17%

1,0%

0,5%

0,0%

UCLA samples (n=102)

12%

0,0%

16%

2,0%

5,9%

0,0%

Olerup SSP® Low resolution Kits – Examples of improved low resolution HLA-A –Improved resolution for A*01,03; A*01,11 and A*03,11 samples • Resolves for example: – 01:01,03:01=03:01,03:18 and 1:01,11:01=11:01,11:94

–Improved resolution for samples containing A*26, A*66 or A*34 alleles • Resolves for example: – 01:01,26:01=03:18,26:01 – 11:01,26:03=03:75,11:10 – 26:01,66:02=26:09,26:65=26:65,43:01 – 66:01,66:02=34:01,66:12

–Improved reactivity pattern for A19-samples • A19-specific vial included – Will decrease risks of new alleles with blank reactivity patterns. Thereby sustaining resolution for homozygous samples

HLA-DR • Improved resolution for DRB1*13,13; DRB1*13,14 and DRB1*14,14 samples • Resolves for example: – – – –

13:01,14:02= 14:21,14:24 14:01,14:02=13:44/86,14:01 13:03,14:01=03:76,14:01=14xx,14xx Improved resolution for samples containing DRB1*03, DRB1*08, DRB1*07, DRB1*09 or DRB1*12

Olerup SSP® Low resolution Kits – Examples of improved low resolution HLA-B –Improved resolution for B*07,39 and B*07,40 samples • Resolves for example: – 07:02,39:01=07:69,67:01 – 07:02,39:02=48:05,67:01 – 07:02,40:01=40:xx, 40:166

–Improved resolution for B62,B63 samples.

Separated from B15- and B62 serological equivalents –Exon 2-3 (Intron 2 spanning) primer pairs included

–Improved resolution for B*35 samples • With respect to B*18-alleles

• Resolves for example: – B*35:01:01:01,51:01:02=B*53:01:01,7 8:02:01

–Improved resolution for B*08:01 homozygous samples –Improved resolution through B*42 specific primer mix • Resolving various ambiguities for samples containing for example B*07, B*08, B*27 or B*39 alleles

Confidential - for internal use only

Olerup SSP® Low resolution Kits – Flexibility and Convenience • Conclusions – Low resolution kit format expansion result in a significant decrease of ambiguities for both sample populations – Possible in new format to include primer pairs spanning Class I intron 2 • resolves for example B*35:01:01:01,51:01:02 = B*53:01:01,78:02:01

• Benefits of the format change – will enable us to continue to: • cover all alleles as databases are released • Sustain high quality low resolution • Increase genotype resolution