Xenopus as an alternative model to study CHIP (Clonal Hematopoiesis of Indeterminate Potential)

Abstract

Clonal hematopoiesis of indeterminate potential (CHIP) is a condition that contains a subpopulation of mutated hematopoietic stem cells (HSCs) or blood progenitor cells without hematologic malignancy. At the beginning of the CHIP condition, only a few parts of HSCs or progenitors are mutated with exposure to risk factors. As time passed, CHIP contributes to giving rise to hematologic diseases such as acute myelogenous leukemia (AML) and atherothrombotic risk. Xenopus laevis has been used as an animal model system for developmental biology. Xenopus embryos have a short period for development and are easy to manipulate genetic characteristics. Especially, it is easy to manipulate only a specific part of the target according to the cell fate map, similar to the case of CHIP. In this study, we used Xenopus laevis as an alternative model system for CHIP and leukemia. Using the CRISPR system, mutation on genes related to hematologic malignancies such as Tet2 and DDX41 was induced in Xenopus embryos. In this procedure, we injected CRISPR into only one part of the blood-lineaged cells to obtain a CHIP-like developmental process. We obtained embryonic blood cells and confirmed blood cell phenotype with Giemsa-Wright staining and quantitative PCR using blood cell markers discovered through Xenopus blood single cell sequencing. We found out that abnormal blood phenotypes were detected in some embryos, and further studies were undergoing.