Could Immunophenotype Guide Molecular Analysis in Patients with Myeloid Malignancies?

Objective: Immunophenotype has been correlated with molecular aberrations in several studies. The aim of this study was the discovery of immunophenotypic features related to mutations in AML and MDS patients connected to prognostic factors. Moreover, an effort to evaluate a method for the detection of the most common NPM1 mutations of exon12 and Internal Tandem Duplications (ITD) mutations of FLT3 gene by flow cytometry was performed. Method: Patients with de novo myeloid neoplasms [ AML and MDS (AML-M3 patients were excluded)] were included. FLT3/ITD/TKD and NPM1 mutations were detected by PCR and fragment analysis. The immunophenotypic analysis was performed by multi-dimensional flow cytometry (FC) with a standardized panel of monoclonal antibodies on peripheral blood or bone marrow samples. Nucleophosmin Antibody and CD135 were used for the mutations immunophenotypic detection. Results: NPM1 and/or FLT3 mutations correlated with low or no expression of more immature cells markers such as CD34, CD117, HLADR, as well as higher expression of more mature markers such as CD11b. The higher expression of CD33 should be mentioned as well. The presence of NPM1mut and FLT3/ITD does not seem to be detectable by FC at least using these two monoclonal antibodies. The presence of CD7 aberrant lymphoid marker’s expression was associated with FLT3mut, NPM1wt genotype. CD56 or CD2 positivity was found only in patients’ samples negative for NPM1 and/or FLT3 mutations. Conclusions: Certain immunophenotype findings including the presence of aberrant lymphoid markers may be indicative of the presence of mutations in NPM1 and FLT3 linked to prognosis

Extracorporeal photopheresis in refractory chronic graft-versus-host disease: The influence on peripheral blood T cell subpopulations. A study by the Hellenic Association of Hematology

Extracorporeal photopheresis (ECP) has been established as an effective treatment modality for patients with chronic extensive graft-versus host disease (GVHD). In the present study, we evaluated the influence of ECP on the numbers of CD4(+), CD8(+), CD20(+), CD56(+) cells, and on T-regulatory (Tregs), as well as on the numbers of naive, central memory (CM), and effector memory (EM) T-cells in patients treated for refractory chronic GVHD. Flow cytometric analysis of peripheral blood lymphocytes was performed for the calculation of the different T-cell subsets. Patients with GVHD had a higher percentage of EM-CD4(+) cells in comparison with healthy donors (p = 0.046). The percentages of naive-CD8(+), naive-CD4(+), CM-CD8(+), CM-CD4(+), EM-CD8(+), and Tregs were not different between patients with GVHD and healthy donors. Similarly there was no statistical difference in the percentages of naive, CM, and EM CD4(+) and CD8(+) cells before and after 3 months of treatment with ECP. However, in the subset of Tregs a statistically significant increase was observed after 3 months of treatment with ECP (p = 0.015). Responders to ECP had statistically significantly higher absolute numbers of CD4(+), and CD8(+) cells, in comparison with non-responders. These data further support the concept that ECP does not cause immune-suppression, but should be better considered as an immune-modulating treatment. (C) 2011 Elsevier Ltd. All rights reserved