Innate T Cells and TKI Discontinuation

Overview

After more than a decade of treating chronic myeloid leukemia (CML) with tyrosine kinase inhibitors (TKI), the discontinuation of treatment represents the expected new revolution. The investigators has recently discovered a new innate CD8+ T population in healthy subjects, the Eomes+ KIR+ CD8+ T population, with anti-tumor properties. Remarkably, these cells are numerically and functionally deficient in patients at diagnosis and then restored in patients in major molecular remission (MMR) on TKI. Our work performed in a retrospective pilot study interestingly shows a very significant increase in the proportion of CD8+ Eomes+ KIR+ T cells within total T cells in patients with prolonged success in stopping their ITK (≥ 2 years).Thus, the investigators postulate that CD8+ Eomes+ KIR+ T cells are a predictive signature of TKI arrest success in CML. The investigators will rely on a prospective translational study of this cell contingent during treatment cessation.

To perform this research, the investigators have started a prospective translational study to collect samples in CML patients with successful versus patients who have failed TKI therapy discontinuation. The investigators plan to study functional and phenotypic characteristics of innate T cells. The investigators also plan to evaluate in vitro whether immune check points inhibitors could help to restore the innate T lymphocytes population.

Conditions

Interventions