(15) evaluated CEBPA promoter methylation in 5 AML and 99 T-ALL cases, with expression of cytoplasmic CD3 and CD7
transcripts, T-cell receptor rearrangement, and NOTCH1 mutations.
The aberrant expression of CD7
showed positivity in 28 (26.4%) cases, most frequently expressed in AML-M2 and CD19 was expressed in 1(1.1%) case.
In spite of CD4, they were negative for other T-cell markers such as CD3, CD5, CD7
, and CD8.
The blasts may show frequent Auer rods and express aberrant CD7
by flow cytometry (Figure 1, A through D).
Various Gal 1 ligands are found on lymphocytes (CD7
, CD43, and CD45), on endothelial cells (CD13, CD36, ROBO4, and integrins), and in the extracellular matrix (fbronectin, integrins, laminin, ROBO4, and GM1) (14).
Eight-color MFC was performed in all patients as a routine clinical test on BM samples that were obtained as part of baseline assessment at the time of diagnosis, the end of the first and second courses of chemotherapy, as well as pre-HSCT., A panel of eight antibody combinations that recognize CD7
, CD11b, CD13, CD14, CD16, CD19, CD33, CD34, CD38, CD41, CD45, CD56, CD61, CD64, CD71, CD117, CD123, and HLA-DR was used for MRD detection, and 0.2-1 million events per tube were acquired on a Fluorescence activated cell sorter (FACS Canto II) (BD Co., USA).
In the immunohistochemical analysis, the tumor cells were positive for LCA, CD3, CD7
, CD8, and CD56, and negative for CD20, CD5, CD4, CD79a, CD10, CD99, and CK.
Total 32 cases (18 children and 12 adults) expressed cross lineage aberrant markers, CD13, CD33 and CD7
In literature, abnormal co-expression of other T-cell antigens, CD2, CD4, CD7
, and CD8, has also been reported.
Peripheral blood flow cytometric immunophenotyping revealed a 40% population of aberrant B-lymphoblasts, that were CD45 (-), CD10 (+), CD22 (+), CD20 variably (+), CD19 (+), HLA-DR variably (+), CD34 partial (+), CD56 partial (+), Tdt (+), and negative for the remaining lymphoid and myeloid markers tested, including CD14, CD5, CD7
, CD33, CD13, CD3, CD4, CD8, CD117, CD16, and MPO (Figure 2).
One of the patients with AML had a subtype M0 with co-expression of CD7
. The sex ratio was as follows: 6 females and 2 males.