One of the MPN-AITL samples in the present study harbored two different IDH2 gene mutations (R172G and R140Q) and was found with barely perceptible IDH2 protein expression, Figure 2B. As the anti-IDH2 antibody used in the present study recognizes wildtype (wt) IDH2 protein, it could be postulated that in this sample, almost no wt IDH2 protein was expressed. This evidence concerns the gene IDH2 and angioimmunoblastic T-cell lymphoma.