HLA-G Expression on Blasts and Tolerogenic Cells in Patients Affected by Acute Myeloid Leukemia

Abstract EN

Human Leukocyte Antigen-G (HLA-G) contributes to cancer cell immune escape from host antitumor responses.

The clinical relevance of HLA-G in several malignancies has been reported.

However, the role of HLA-G expression and functions in Acute Myeloid Leukemia (AML) is still controversial.

Our group identified a subset of tolerogenic dendritic cells, DC-10 that express HLA-G and secrete IL-10.

DC-10 are present in the peripheral blood and are essential in promoting and maintaining tolerance via the induction of adaptive T regulatory (Treg) cells.

We investigated HLA-G expression on blasts and the presence of HLA-G-expressing DC-10 and CD4+ T cells in the peripheral blood of AML patients at diagnosis.

Moreover, we explored the possible influence of the 3′ untranslated region (3′UTR) of HLA-G, which has been associated with HLA-G expression, on AML susceptibility.

Results showed that HLA-G-expressing DC-10 and CD4+ T cells are highly represented in AML patients with HLA-G positive blasts.

None of the HLA-G variation sites evaluated was associated with AML susceptibility.

This is the first report describing HLA-G-expressing DC-10 and CD4+ T cells in AML patients, suggesting that they may represent a strategy by which leukemic cells escape the host’s immune system.

Further studies on larger populations are required to verify our findings.