Glycolytic metabolism of pathogenic T cells enables early detection of GvHD by 13C-MRI.

Graft-versus-host disease (GvHD) is a prominent barrier to allogeneic hematopoietic stem cell transplantation (HSCT). Definitive diagnosis of GvHD is invasive and biopsies of involved tissues pose a high risk of bleeding and infection. Our previous studies in a chronic GvHD mouse model demonstrated that alloreactive CD4+ T cells are distributed to target organs ahead of overt symptoms, meanwhile CD4+ T cell activation is tied to increased glycolysis. We aimed to compare the gene expression of allogeneic (mismatched) naive (Tn) and effector memory (Tem) CD4+ T cell subsets early post transplant. Specifically, we hypothesized that allogeneic CD4 effector memory T cells would show upregulated expression of genes related to glycolysis. We found that almost all enzymes of glycolysis were upregulated in effector memory CD4 T cells compared to naive cells, including transporters for glucose. In contrast, enzymes of the tricarboxylic acid cycle were not uniformly elevated. FACS-purified CD45+ CD4+ cells were isolated from syngeneic and allogeneic transplanted mice (n= 3 each) in a model of chronic GvHD on day 14 from the liver. After sorting, cells were counted, tested for viability and a target of 6000 cells was loaded onto the 10X system. The cells were processed according to the instructions for the 5' sequencing kit.