QTL analyses of lineage-negative mouse bone marrow cells labeled with Sca-1 and c-Kit

Abstract

Differences in the number of functionally and/or phenotypically defined bone marrow cells in inbred mouse strains have been exploited to map quantitative trait loci (QTL) that determine the variation in cell frequency. To extend this approach to the differences in the stem/progenitor cell compartment in CBA/H and C57BL/6 mice, we have exploited the resolution of flow cytometry and the power of QTL analyses in 124 F2 mice to analyse lineage negative (Lin -) bone marrow cells according to the intensity of labelling with Sca-1 and c-Kit. In the Lin -Sca-1 + c-Kit + enriched population six quantitative trait loci (QTL) were identified -one significant and five suggestive. Whereas previous in vitro clonogenic, LTIC-IC, CAFC day 35, and flow cytometry each identified different QTL, our approach identified the same or very similar QTL at all three loci (Chromosome 1, 17 and 18) as well as QTL on chromosomes 6 and 10. In silico analyses implicate haematopoietic stem cell homing involving Cxcr4 and Cxcl12 as being the determining pathway. The mapping of the same or very similar QTLs in independent studies using different assay(s) suggests a common genetic determinant, and thus reinforces the biological and genetic significance of the QTL. These data also suggest that mouse bone marrow cell subpopulations can be functionally, phenotypically and genetically defined.3

The Genetic Landscape of Hematopoietic Stem Cell Frequency in Mice

“…With the development of immunophenotypic markers that could identify functional HSPCs ( Morrison and Weissman, 1994 ), flow cytometric analysis has been used to identify QTLs for HSPC frequency in the BXD RI panel, but this approach has only been successful in aged mice ( Henckaerts et al., 2002, 2004 ). In addition, QTLs for HSPCs distinct from those mapped in the BXD RI panel have been identified using different inbred mouse strains ( Morrison et al., 2002; van Os et al., 2006; Jawad et al., 2008 ), suggesting that the limited variation in crosses between two strains restricts the identification of other genetic factors that play a role in HSPC physiology. Furthermore, the classical QTL approach has inherently low mapping resolution, since the regions of interest typically span large chromosomal intervals and can contain hundreds to thousands of genes.…”

Effect of human umbilical cord blood derived lineage negative stem cells transplanted in amyloid-β induced cognitive impaired mice

“…Such primitive population of cells are deprived of any mature hematopoietic markers such as, CD2, CD3, CD14, CD16, CD19, CD24, CD56, CD66b, and CD235a (glycophorin A) [28] and found to be present in only 0.1% population of mono-nucleated cells enriched from hUCB [29] These are also found in peripheral blood and bone marrow cell in a very limited fraction [30,31]. These cells were shown to have the potential to differentiate into granulocytemacrophage, erythroid and megakaryocytic colony forming units when cultured in-vitro [32].…”