HLA Department
The workplace is integrated into the Complement of Laboratories IHBT. It continuously upholds an independent and impartial assessment of the professional competence of the Complement of Laboratories according to the ČSN EN ISO 15189 standard, the application of which is verified by the Czech Institute for Accreditation. Examination methods within the scope of accreditation are defined by the annex to the Accreditation Certificate in its current version. It is available on the website IHBT.
The HLA Department performs specialized genetic examinations of patients and donors of hematopoietic stem cells and further examines samples from patients with suspected congenital HLA predisposition to diseases such as celiac disease. All examinations are performed using molecular genetics methods.
When examining patients and searching for suitable hematopoietic stem cell donors, the department tests the main human immune system – HLA (Human Leukocyte Antigens) at high resolution level using massively parallel sequencing technology. Additionally, KIR genes (killer cell immunoglobulin-like receptors) are also tested for these purposes.
Within the framework of testing HLA association with diseases, particularly HLA genes associated with celiac disease risk, the department works as a reference laboratory and ensures and coordinates the exchange of information with other DNA laboratories in the Czech Republic. It further provides consulting services and organizes interlaboratory comparisons of tests.
Since 2007, the department has been accredited by the international professional organization European Federation for Immunogenetics. As part of this organization, we regularly successfully participate in international quality control checks for all performed examinations. The HLA Department is part of the NRL for DNA diagnostics.
Employees are bound by confidentiality in accordance with theHealth Services Act, Act No. 372/2011 Coll.
Trust and high data security is one of the fundamental priorities within the activities of the Complement of Laboratories IHBT. Established procedures take place in accordance with the Personal Data Protection Act 110/2019 Coll., and Regulation (EU) 2016/679 of the European Parliament and of the Council of 27 April 2016 on the protection of natural persons with regard to the processing of personal data and on the free movement of such data and repealing Directive 95/46/EC. More information is available on the website IHBT.
HLA system genotyping has been performed by the HLA Department since 1993 as the first in the Czech Republic for the needs of patients IHBT, the Clinic of Pediatric Hematology and Oncology FN Motol and other clinical requesters.
The HLA system (Human Leukocyte System) is the main histocompatibility system of humans. Genetically, it is mapped to the short arm of chromosome 6 (to position 6p21.31 - 6p21.33). The products of its extremely polymorphic genes are antigenic structures (transmembrane glycoproteins) that recognize foreign structures to the organism and thereby initiate a cascade of immune responses.
Determining the precise HLA genotype in a patient and their donor is one of the fundamental conditions for the success of allogeneic hematopoietic stem cell transplantation. Discordance in the HLA region between the donor and transplant recipient can induce graft rejection, or may cause Graft Versus Host Disease (GvHD), which is a serious or potentially fatal complication.
Currently, we routinely perform genotyping of the most important transplantation loci of HLA class I and II: HLA-A, HLA-B, HLA-C, DRB1, DQB1, DQA1 and DPB1 in patients indicated for allogeneic hematopoietic stem cell transplantation and as confirmatory examination for unrelated donors selected for them from Czech and foreign registries.
Association of some diseases (e.g. rheumatoid arthritis, celiac disease, narcolepsy, insulin dependent diabetes mellitus) with specific HLA system alleles is also known, which manifests as an increase in relative risk of disease when the given allele is present. However, none of these associations is absolute.
The laboratory determines HLA markers associated with diseases:
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HLA-B*27 positivity for association with rheumatoid diseases
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DQB1*06:02 positivity for determining association with narcolepsy
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DQB1 and DQA1 alleles associated with celiac disease according to the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition Guidelines for the Diagnosis of Coeliac Disease
For the listed HLA markers, the laboratory organizes annual EQA programs for interested parties.
By agreement, we also perform genotyping of selected HLA system loci as supplementary information for the diagnosis of some HLA-associated diseases.
The study of the HLA system is also an important tool in pharmacogenetics, where an HLA marker can predict the responsiveness/non-responsiveness or sensitivity of a patient to the administration of a therapeutic drug (e.g. administration of Abacavir in HIV-positive patients).
For genotyping, we use a range of precise methods:
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PCR method with gel electrophoresis (PCR-SSP) massively parallel sequencing (NGS) real-time PCR method
Result evaluation is performed using special software that is linked to the international HLA allele database and is regularly updated depending on this database. This ensures maximum informativeness of the results issued.