Validity of human leukocyte antigen class ii typing in-house assay in comparison with commercial kit

ABSTRACT

To determine the validity of in-house assay for DNA based HLA class II typing against commercial kit as gold standard. Validation Study. Department of Immunology, Armed Forces Institute of Pathology, Rawalpindi, from Feb 2006 to March 2007. 56 cases referred to Immunology Department for HLA class II typing were included in the study and each subject tested by both the assays. INNO-LiPA assay was done by commercial kits which are based on sequence specific oligonucleotide probes. For in-house assay, individual reagents were obtained from commercial sources and protocol of the assay was established. The results of in-house assay were compared with INNO-LiPA kit. The sensitivity and specificity of in-house assay as compared to commercial assay were calculated, for each of the individual alleles identified, and at the end, cumulative sensitivity and specificity were found to be 92% and 99% respectively. High sensitivity, specificity, cost effectiveness and being easy to perform, make in-house assay a suitable alternative approach for performing HLA-DRB1 typing, especially in renal transplant patients where it can replace serological techniques. In addition, with the addition of primers for new alleles, it can be used to resolve any ambiguity that arises during the course of commercial testing. However, further work is required to study and analyze primers for DRB1 03 and DRB115, to make in-house assay, a cost effective method for low resolution typing