The following is a summary of the “Circulating extracellular vesicles as a predictive biomarker for acute graft-versus-host disease,” published in the January 2023 issue of Hematology by Carneiro, et al.

Allogeneic stem cell transplantation has been successful in saving lives, but the detection and treatment of graft-versus-host disease (GVHD) have remained significant obstacles (allo-SCT). To further improve on patient outcomes, new diagnostic technologies and therapeutic strategies are required. Biomarkers of cellular injury, activity, and intercellular signalling, extracellular vesicles (EV) are microvesicles generated by the inversion of the phospholipid bilayer of many cellular subtypes. 

They examined whether or not there was a correlation between EV concentrations and the occurrence of acute GVHD (aGVHD). Around 40 patients with haematological malignancies who were receiving allo-SCT had their plasma sampled during the time when the neutrophils were engrafting. Fluorescent bead flow cytometry was used to determine the percentage of EVs that were annexin V positive, the percentage of EVs that were CD61 positive for platelets, and the percentage of EVs that were CD235 positive for erythrocytes (EryEV).

The cumulative incidence (CI) of grade II to IV aGVHD was higher in patients with TEV counts larger than 516/L (54% vs. 21%; P = 0.02) and in those with EryEV counts greater than 357/L (59% vs. 26%; P = 0.04). High TEV and EryEV counts are more strongly associated with aGVHD in patients who undergo reduced intensity conditioning (RIC) (77% vs. 22%; P = 0.003 and 89% vs. 27%; P = 0.002, respectively). The risk of developing aGVHD was not correlated with PEV concentrations. They conclude that measuring cell-derived EV upon engraftment can serve as a prophylactic biomarker for acute GVHD.

Source: sciencedirect.com/science/article/pii/S0301472X22008086