Anti-human leukocyte antigen DQ antibodies in renal transplantation: Are we underestimating the most frequent donor specific alloantibodies?

Clinical Significance of HLA-DQ Antibodies in the Development of Chronic Antibody-Mediated Rejection and Allograft Failure in Kidney Transplant Recipients

“…Therefore, the immune system stimulated by sensitizing events such as transplantation, pregnancy, or transfusion is most likely to form antibodies against HLA-DQ. 16 DQ-DSA was most commonly accompanied by DSA against HLA-DR in our study, which is also consistent with results from previous studies. 3 , 9 , 10 This may be explained by the strong linkage disequilibrium between the DQ and DR locus, and which is probably why the two are often inherited together within the same racial or ethnic group.…”

“…As a result, DQ-DSA proved to be the most commonly detected type not only in the entire cohort but also in the subgroup comprised of previously nonsensitized patients, which is consistent with previous studies. 9 – 11 , 16 The high frequency of DQ-DSA found after transplantation may be explained by the high polymorphism of the genes which encode the DQ molecule (DQA1 and DQB1). Therefore, the immune system stimulated by sensitizing events such as transplantation, pregnancy, or transfusion is most likely to form antibodies against HLA-DQ.…”

De-Novo Donor Specific DQ Antibody in AMR and Need for Extended HLA Typing

“…There is literature to suggest that there is a high frequency of antibodies formed to DQ antigens post transplant due to the highly polymorphic nature if the genes encoding for the molecule. Hence sensitizing events lead to formation of DQ antibodies by the immune system [20]. Interpretation of DQ antibodies has been extensively discussed by Haarberg et al [10] suggesting that since HLA class II antigens are composed of two chains, α and β it is important to consider the contribution of both while analyzing antibodies rather that beta chain alone, as has been common practice [10].…”

Two Cases of Antibody-Mediated Rejection Following Kidney Transplantation due to HLA-DQB1 Allele-Specific and DQ Alpha Protein-Specific HLA Antibodies

“…Recent studies using single antigen bead-based assays (SABAs) have revealed that HLA-DQ donor-specific HLA antibodies (DSHAs) are associated with inferior allograft outcomes [12]. Therefore, donor HLA-DQ typing prior to transplantation is now thought to be highly important.…”