Report from the Proficiency Testing of HLA Class I Typing for Central / East Europe

Katarzyna Bogunia-Kubik, Anna Laba, Bartosz Grzywacz, Malgorzata Polak & Andrzej Lange

Unit of Quality Control and Standardisation, Department of Clinical Immunology, Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland

Success of many transplants, in particular allogeneic hematopoietic stem cell transplantation largely depends on optimal donor selection. It is based on HLA typing results. HLA can be typed by serology and at the DNA level. Molecular biology techniques (i.e. PCR-SSP, PCR-SSO, SBT) offer greater specificity and range of alleles detected.

Lack of the use of standardised procedures for HLA typing and an increased number of new HLA allelic specificities (frequently not typed by serology) provided a strong indication for implementation of the quality control system in Poland. In November 1999 we started to run the Quality Control Workshop for Polish HLA labs (Bogunia-Kubik K et al. Report from the Quality Control Workshop for HLA typing. Acta Haematologica Polonica, 2000, 2, 213-219.). To date 3 rounds of the standardisation exercise were organised. In the first one, five out of eleven invited institutions responded positively and took part in the standardisation trial. In the next trial eight laboratories were involved. Each centre received four blood samples for serological typing of HLA class I and 5 samples for DNA HLA class II typing. Four of the samples for DNA typing contained 30-100 ng/ml of DNA isolated with the use of Qiagen kit. HLA class II typing should be performed as least for DRB1 alleles at the low resolution level.

The success of two national trials prompted us to expand the activity to the Central East European area. As a result the third national workshop was combined with The Proficiency Testing of HLA Class I for Central East (CE) Europe. The letters with an information and invitation were sent to 23 laboratories involved in HLA typing in CE Europe. Altogether 17 laboratories took part in this trial. Nine institutions from abroad and 8 Polish laboratories were involved. Four volunteer donors were invited to donate blood for typing. From each donor two blood samples, one taken on heparin and one on EDTA, were taken and sent by a courier post to each centre for HLA-class I typing either by serology or at the DNA level. Results adequate to serological typing / DNA low resolution were expected.

Fifteen out of 17 laboratories received the samples within 48 hours and two others with a substantial delay. For one lab the delay prevented the typing. Fifteen out of 17 labs returned the results of the trial. Three laboratories submitted only DNA typing results. Three other laboratories submitted separately both, serological and genetical typing results. Two institutions submitted combined results where HLA specificities were typed using both (serology and DNA typing) techniques. Other participating laboratories typed the HLA class I antigens only by serology. Each laboratory was given a Lab code. All participating institutions were provided with tables with all submitted typing results. The proper typing results were given together with a sample number in bold. Discrepancies were given in italic and underlined. The proper typing results of standardisation samples are presented in Table 2.

Due to some delay in sending the quality control samples one lab did not complete typing and the other laboratory did not type any sample. One laboratory received 3 out of 4 standardisation samples. One laboratory did not submit the results although the samples reached the destination institution without any delay. HLA-A and B specificities were typed by all laboratories regardless the technique used. HLA-C specificities were not analysed in 5 institutions.

Altogether 18 results were submitted including HLA class I typing by serology, DNA typing or with the use of both methods. HLA-A typing results were discrepant in 6 cases, HLA-B in 8 and HLA-C in 18 cases.

The discrepancies in HLA-A results were mainly connected with Sample 3 where 3 laboratories detected in addition a specificity not actually being detected in a primary homozygous regarding locus A situation. There was also one erroneous typing of Sample 2. One laboratory did not submit the results.

Two samples, Sample 3 and 4, were typed properly with respect to the HLA-B specificities by all participating laboratories. Typing of Sample 1 caused a problem for three labs (two failed to type splits of B5 and B15 and one did not submit typing results). Discrepancies in HLA-B typing of Sample 2 were seen in 5 cases. One lab failed to type one HLA-B specificity and one was unable to type both HLA-B specificities. Two other labs performed wrong typing of B55 antigen and one did not type the splits of B22.

Most labs had problems with HLA-C locus typing. Five labs did not type antigens of this locus. Number of erroneous typings was also higher than for A and B. The percentage of concordant results was the lowest of all HLA class I loci (33-45%, Table 3). Altogether 24 out of 72 typings were discrepant. In a number of situations Internet connections was used and this was facilitated by a support offered by RETRANSPLANT project.

The results were discussed against the consensus typing. In the future all samples will be typed with the use of SBT to provide genetical typing results as a background to consensus typing data and making a choice of cells to be sent we will cover all the most frequent antigens.

Presented here Class I Proficiency Testing Exercise will be continued with sending the sample sets in 4 months interval and organisation of the workshop will be consistent with the "Proposal of new rules for EFI Proficiency Testing" (EFI Newsletter, 2000, 30, 1). In organising the Class I Quality Control Workshop we joined the activity of the Vienna centre organising successfully Quality Control Workshop for DNA based HLA class II Typing.

This work was supported in a part by RETRANSPLANT project. The authors are grateful to Dr E. van den Berg-Loonen and Dr J.-M. Tiercy for critical comments.

Table 1. Participants in the CE European Quality Control Workshop for HLA Class I Typing

1. Ludmila Bubnova, St. Petersburg, Russia
2. Irena Bugajna, Walbrzych, Poland
3. Zuzana Cermakova, Ostrava, Czech Rep.
4. Eva Gyodi, Budapest, Hungary
5. Andrija Kastelan, Zagreb, Croatia
6. Miroslaw Klos, Warszawa Poland
7. Eniko Kulcsarova, Bratislava, Slovakia
8. Andrzej Lange, Wroclaw, Poland
9. Radvile Malaickaite, Vilnus, Lithuania
10. Andrzej Miklaszewicz, Szczecin, Poland
11. Grazyna Moszkowska, Gdansk, Poland
12. Elissaveta Naumova, Sofia, Bulgaria
13. Martin Petrek, Olomouc, Czech Rep.
14. Ildko B. Petri, Szeged, Hungary
15. Anna Pituch-Noworolska, Krakow, Poland
16. Urszula Siekiera, Katowice, Poland
17. Grzegorz Woszczek, Lodz, Poland

Table 2. DNA typing results at the low resolution level of standardisation samples.

Table 3. Percentage of concordant results for HLA-A, B and C locus in each standardisation sample.

# - Sample No 1 was not sent to one institution.

© The European Federation for Immunogenetics
Page Created 10 July, 2002, Last Modified 1 August, 2006