Application of a radiosensitivity flow assay in a patient with DNA ligase 4 deficiency.

ABSTRACT: DNA ligase 4 deficiency (LIG4-SCID) causes lymphopenia (T-B-NK⁺) and a radiosensitive SCID (RS-SCID) phenotype. We demonstrate, for the first time, flow cytometric-based kinetic analysis of phosphorylated H2AX (γH2AX) in lymphocyte subsets, especially NK cells, for the assessment of LIG4-SCID. Measurement of phosphorylated (p) ATM, SMC1, and H2AX (γH2AX) was performed by flow cytometry to assess DNA repair defects in a 3-year-old girl. Functional assessment (phosphorylation) was measured in T and NK cells (B cells were absent) before irradiation (background control) or after low-dose (2Gy) irradiation (1 and 24 hours). We observed maximal γH2AX at 1 hour postirradiation, with dephosphorylation at 24 hours postirradiation in healthy control patients. The patient showed normal fre

SUBMITTER: Buchbinder D 

PROVIDER: S-EPMC6093729 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature