Project description:The adaptor protein Lnk is an important negative regulator of HSC homeostasis and self-renewal. This study aims to investigate the role of Lnk in HSC aging. Here we performed expression profiling of bone marrow CD150+CD48-LSK LT-HSCs from young and old WT and Lnk-/- mice. Results identify select Lnk-mediated pathways with potential involvement in HSC self-renewal and aging. CD150+CD48-LSK HSCs were double sorted from WT and Lnk-/- mice at both young and old ages (2 months and 20 months, respectively). RNA was isolated using miRNeasy kit from QIAGEN and processed using the NuGEN Pico kit. The microarray analysis was performed at the Penn Molecular Profiling/Genomics Facility using GeneChip Mouse Gene 1.0ST array (Affymetrix).
Project description:The adaptor protein Lnk is an important negative regulator of HSC homeostasis and self-renewal. This study aims to investigate the role of Lnk in HSC aging. Here we performed expression profiling of bone marrow CD150+CD48-LSK LT-HSCs from young and old WT and Lnk-/- mice. Results identify select Lnk-mediated pathways with potential involvement in HSC self-renewal and aging.
Project description:Aged hematopoietic stem cells (HSCs) display myeloid-biased differentiation and reduced regenerative potential. In this study, we uncover that P-selectin (Selp) marks a subset of aged HSCs with reduced repopulation capacity. This population of HSCs expresses a prominent aging transcriptome. Overexpression of Selp in young HSCs impaired long-term reconstitution potential and repressed erythropoiesis. We show that IL-1β is elevated in aged bone marrow and administration of IL-1β induces expression of Selp and other aging-associated genes in HSCs. Finally, we demonstrate that transplantation of aged HSCs into young recipients restores a young-like transcriptome, specifically by repressing pro-inflammatory pathways, highlighting the important role of the bone marrow microenvironment in HSC aging.
Project description:To describe the protein profile in hippocampus, colon and ileum tissue’ changing after the old faeces transplants, we adopted a quantitative label free proteomics approach.
Project description:Using RNA sequencing analysis on myeloid biased HSC, we compared gene expression profiles between WT and Igf2bp2 knock-out mice at young and old age. 1421 differentially expressed genes were identified in young myeloid biased HSC from Igf2bp2 knock-out mice compared to young WT; however, only 26 differentially expressed genes were identified in old myeloid biased HSC from Igf2bp2 knock-out mice compared to old WT. Compared to young WT myeloid biased HSC, myeloid biased HSC from young Igf2bp2 knock-out exhibits reduced expression of genes involved in metabolism and translation. In addition, single cell RNA sequencing analysis of myeloid biased HSC in young wildtype mice identified nine sub-clusters. HSCs from a sub-cluster with high expression of Igf2bp2 exhibit up-regulated IGF/PI3K/AKT signaling and increased expression of genes involved in HSC quiescence and maintenance. Altogether, the study provides a correlation and mechanism to understand the role of Igf2bp2 in HSC function and aging.
Project description:Purpose: Compare the transcriptome of hematopoietic stem cells (HSCs) that were aged in old and young niches Methods: barcoded GFP+ HSCs were FACS-sorted from a) three recipient mice 15 months post transplantation, and b) six serial transplantation recipient mice 5 months after the 8th transplantation, then subjected to processed using the Chromium Single-cell 3′ v2 Library Kit (10× Genomics, Pleasanton, CA) following the manufacturer’s instructions Results: we obtained transcriptomes of about 12k HSCs aged in young niche, and about 10k HSCs aged in old niche, with the average sequencing depth at close to 50k reads per cell Conclusions: we identified striking differences in gene expression profiles 1) between HSCs aged in young niches from mice with early aging and from mice with delayed aging, and 2) between HSCs aged in old niches and young niches when mice exhibited hematopoietic aging phenotype
Project description:In this project two sets of proteomic experiments were performed: (1) Autophagosome content profiling: Autophagosomes were isolated from cultured primary lung endothelial cells of LC3-GFP and WT mice using anti-GFP uMACS (n=3 biological replicates). (2) Expression proteomics: Protein lysates from endothelial cells of n=3 young and old WT mice, young and old vecCRE-ATG5flox mice (ATG5 KO mice).