HLA-DR Typing By PCR-SSP And Comparison Of Serologic Results With This Method

Document Type : Original Article


Immunology Department, Biotechnology Department, Faculty of medicine, Medical University of Isfahan, Isfahan, Iran


Introduction: Considering the role of HLA matching in transplant outcome, the quality of HLA-DR typing is clearly an important issue.In recent years serologic methods have been replaced with DNA based typing methods.The main objective of this study was to compare HLA-DR typing data obtained from existing serologic method with that obtained by the new PCR-SSP method.
Material and Methods: Fifty-five peripheral blood samples were collected from randomly selected individuals who reffered to the transplantation laboratory of Isfahan in Aliasghar Hospital and was typed for HLA-DR antigens by both methods. HLA-DR typing by serologic method was performed using 30 different antisera and for PCR-SSP method specific primers were used for HLA-DRB1*01-10(except DR6, 8, 10) and also for HLA-DR52 and DR53. After DNA extraction 13 pairs of specific primers were used for each sample separately and PCR reaction was performed. In this study the third intron of DR locus was used as internal positive control. After PCR amplification, electrophoresis on 2% agarose gel was performed on reaction products, and after photography of gel ,interpretation and comparison of results was performed.
Results: The results of 31 samples (56.3%) correlated completely with serologic method. 12 samples (22%) had been assigned heterozygous in serology and homozygous in molecular typing, 7 samples (12.7%) were heterozygous in both methods but different in one allele, 2 samples (3.6%) were homozygous in serology and heterozygous in molecular typing, and also one sample (1.8%) was homozygous in both methods; that is serologically DR14 positive and moleculary DR11 positive. And finally 2 samples of 55 (3.6%) were not definable by in serologic method.
Conclusion: The data obtained from the conventional and the new method were compared. Sensitivity,specificity and rate of discrepancy between the two methods were discussed.