PROJECT: JTC2022 - Cerebrovascular: CH-Stroke

Clonal Haematopoiesis in Ischemic Stroke

Abstract

Stroke incidence is rising with aging, as does the prevalence of leukaemia-associated mutations in hematopoietic stem cells, known as clonal haematopoiesis (CH). In an incident stroke cohort, we identified a strong association of TET2 mutations and clone size with combined vascular endpoints in a three-year follow-up. The impact of CH on stroke damage and outcome is unknown. We will model CH in mice using TET2 KO or WT BM chimeras and various clone sizes. Stroke will be induced by transient middle cerebral artery occlusion and invading BM cells that have a myeloid bias due to the TET2 mutation will be traced by CD45.1 expression. Damage and structural plasticity will be assessed by MRI (T2 incidence maps and diffusion tensor imaging) and functional recovery by daily behavioral testing. The fate, and activity of invading mutant cells in ischemic brains will be determined by index sorting of CD45.1 and scRNAseq and histology (7 and 21 days). The recipient response will be studied by RiboTag-based translatome analysis and tracer injections to monitor BBB leakage. Impact of graft cells on microenvironment will be analysed by microdialysis in awake mice after stroke and in the blood. In an exploratory translational experiment, the established clone size of mutant Tet2 BM with the largest effect on stroke outcome will be treated with neuralizing anti-IL-1b, expecting mice with a burden of a large Tet2 mutant clone size will benefit more than littermates with WT BM chimerism.

Keywords

Omics approaches Imaging techniques Gene targeting in the brain Molecular modelling techniques Behavioural methodologies Animal studies

Call topic

Cerebrovascular

Proposed runtime

n/a - n/a

Project team

Christoph Harms (Coordinator)
Germany (DFG)
Steffen Jung
Israel (CSO-MOH)
Anna Malik
Poland (NCBR)
Matthias Endres
Germany (DFG)
Daniel Lewandowski
France (ANR)