L-Calc™ Software

Software for limiting dilution analysis

More Views

L-Calc™ Limiting Dilution Software

Software for limiting dilution analysis

N/A
Catalog #28600
.

Overview

Limiting Dilution Analysis (LDA) has been applied to the in vitro quantitation of hematopoietic stem cells (HSCs) using assays such as the long term culture-initiating cell (LTC-IC) assay (Conneally et al.) and the cobblestone area forming cell (CAFC) assay (Wang et al.). Limiting dilution protocols have also been adapted to allow the quantitation of human and mouse HSCs with the capacity to produce mature cells of all hematopoietic lineages in vivo, in competitive repopulating unit (CRU) (Ploemacher et al.; Szilvassy et al.) and SCID repopulating cell (SRC) assays (Dick et al.).

L-Calc™ will assist you in analyzing the results of your LDA. For each experiment, values corresponding to dose (i.e. cells per well); total number of positive responses obtained per dose; and total number of replicates tested (i.e. total number of wells used per cell dose) are entered. From these data, the frequency of cells within a given cell population capable of a defined response is determined. L-Calc™ can also be used as a guide to assess differences between paired sets of LDAs. A statistician should be consulted to perform the appropriate comparison.

Free Software Download Available: lcsetup.exe

Suitable for use with Microsoft® Windows.
Please note we no longer provide support or updates for L-Calc software.
Application:
Functional Assay
Area of Interest:
Stem Cell Biology

Technical Resources

Educational Materials

(2)

Product Applications

This product is designed for use in the following research area(s) as part of the highlighted workflow stage(s). Explore these workflows to learn more about the other products we offer to support each research area.

Data and Publications

Publications

(16)
Blood 2011 JUL

Crebbp haploinsufficiency in mice alters the bone marrow microenvironment, leading to loss of stem cells and excessive myelopoiesis.

Zimmer SN et al.

Abstract

CREB-binding protein (CREBBP) is important for the cell-autonomous regulation of hematopoiesis, including the stem cell compartment. In the present study, we show that CREBBP plays an equally pivotal role in microenvironment-mediated regulation of hematopoiesis. We found that the BM microenvironment of Crebbp(+/-) mice was unable to properly maintain the immature stem cell and progenitor cell pools. Instead, it stimulates myeloid differentiation, which progresses into a myeloproliferation phenotype. Alterations in the BM microenvironment resulting from haploinsufficiency of Crebbp included a marked decrease in trabecular bone that was predominantly caused by increased osteoclastogenesis. Although CFU-fibroblast (CFU-F) and total osteoblast numbers were decreased, the bone formation rate was similar to that found in wild-type mice. At the molecular level, we found that the known hematopoietic modulators matrix metallopeptidase-9 (MMP9) and kit ligand (KITL) were decreased with heterozygous levels of Crebbp. Lastly, potentially important regulatory proteins, endothelial cell adhesion molecule 1 (ESAM1) and cadherin 5 (CDH5), were increased on Crebbp(+/-) endothelial cells. Our findings reveal that a full dose of Crebbp is essential in the BM microenvironment to maintain proper hematopoiesis and to prevent excessive myeloproliferation.
Blood 2011 JAN

Angiopoietin-like protein 3 supports the activity of hematopoietic stem cells in the bone marrow niche.

Zheng J et al.

Abstract

The physiologic roles of angiopoietin-like proteins (Angptls) in the hematopoietic system remain unknown. Here we show that hematopoietic stem cells (HSCs) in Angptl3-null mice are decreased in number and quiescence. HSCs transplanted into Angptl3-null recipient mice exhibited impaired repopulation. Bone marrow sinusoidal endothelial cells express high levels of Angptl3 and are adjacent to HSCs. Importantly, bone marrow stromal cells or endothelium deficient in Angptl3 have a significantly decreased ability to support the expansion of repopulating HSCs. Angptl3 represses the expression of the transcription factor Ikaros, whose unregulated overexpression diminishes the repopulation activity of HSCs. Angptl3, as an extrinsic factor, thus supports the stemness of HSCs in the bone marrow niche.
Blood 2010 MAR

Slug deficiency enhances self-renewal of hematopoietic stem cells during hematopoietic regeneration.

Sun Y et al.

Abstract

Both extrinsic and intrinsic mechanisms tightly govern hematopoietic stem cell (HSC) decisions of self-renewal and differentiation. However, transcription factors that can selectively regulate HSC self-renewal division after stress remain to be identified. Slug is an evolutionarily conserved zinc-finger transcription factor that is highly expressed in primitive hematopoietic cells and is critical for the radioprotection of these key cells. We studied the effect of Slug in the regulation of HSCs in Slug-deficient mice under normal and stress conditions using serial functional assays. Here, we show that Slug deficiency does not disturb hematopoiesis or alter HSC homeostasis and differentiation in bone marrow but increases the numbers of primitive hematopoietic cells in the extramedullary spleen site. Deletion of Slug enhances HSC repopulating potential but not its homing and differentiation ability. Furthermore, Slug deficiency increases HSC proliferation and repopulating potential in vivo after myelosuppression and accelerates HSC expansion during in vitro culture. Therefore, we propose that Slug is essential for controlling the transition of HSCs from relative quiescence under steady-state condition to rapid proliferation under stress conditions. Our data suggest that inhibition of Slug in HSCs may present a novel strategy for accelerating hematopoietic recovery, thus providing therapeutic benefits for patients after clinical myelosuppressive treatment.
Blood 2010 DEC

Progenitor cell dose determines the pace and completeness of engraftment in a xenograft model for cord blood transplantation.

Liu C et al.

Abstract

Two critical concerns in clinical cord blood transplantation are the initial time to engraftment and the subsequent restoration of immune function. These studies measured the impact of progenitor cell dose on both the pace and strength of hematopoietic reconstitution by transplanting nonobese diabetic/severe combined immunodeficiency/interleukin-2 receptor-gamma-null (NS$) mice with lineage-depleted aldehyde dehydrogenase-bright CD34(+) human cord blood progenitors. The progress of each transplant was monitored over an extended time course by repeatedly analyzing the peripheral blood for human hematopoietic cells. In vivo human hematopoietic development was complete. After long-term transplantation assays (≥ 19 weeks), human T-cell development was documented within multiple tissues in 16 of 32 NS$ mice. Human T-cell differentiation was active within NS$ thymuses, as documented by the presence of CD4(+) CD8(+) T-cell progenitors as well as T-cell receptor excision circles. It is important to note that although myeloid and B-cell engraftment was detected as early as 4 weeks after transplantation, human T-cell development was exclusively late onset. High progenitor cell doses were associated with a robust human hematopoietic chimerism that accelerated both initial time to engraftment and subsequent T-cell development. At lower progenitor cell doses, the chimerism was weak and the human hematopoietic lineage development was frequently incomplete.
Blood 2008 APR

Angiopoietin-like 5 and IGFBP2 stimulate ex vivo expansion of human cord blood hematopoietic stem cells as assayed by NOD/SCID transplantation.

Zhang CC et al.

Abstract

Hematopoietic stem cells (HSCs) are the basis of bone marrow transplantation and are attractive target cells for hematopoietic gene therapy, but these important clinical applications have been severely hampered by difficulties in ex vivo expansion of HSCs. In particular, the use of cord blood for adult transplantation is greatly limited by the number of HSCs. Previously we identified angiopoietin-like proteins and IGF-binding protein 2 (IGFBP2) as new hormones that, together with other factors, can expand mouse bone marrow HSCs in culture. Here, we measure the activity of multipotent human severe combined immunodeficient (SCID)-repopulating cells (SRCs) by transplantation into the nonobese diabetic SCID (NOD/SCID) mice; secondary transplantation was performed to evaluate the self-renewal potential of SRCs. A serum-free medium containing SCF, TPO, and FGF-1 or Flt3-L cannot significantly support expansion of the SRCs present in human cord blood CD133+ cells. Addition of either angiopoietin-like 5 or IGF-binding protein 2 to the cultures led to a sizable expansion of HSC numbers, as assayed by NOD/SCID transplantation. A serum-free culture containing SCF, TPO, FGF-1, angiopoietin-like 5, and IGFBP2 supports an approximately 20-fold net expansion of repopulating human cord blood HSCs, a number potentially applicable to several clinical processes including HSC transplantation.
STEMCELL TECHNOLOGIES INC.’S QUALITY MANAGEMENT SYSTEM IS CERTIFIED TO ISO 13485. PRODUCTS ARE FOR RESEARCH USE ONLY AND NOT INTENDED FOR HUMAN OR ANIMAL DIAGNOSTIC OR THERAPEUTIC USES UNLESS OTHERWISE STATED.
Chat with an Expert