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Invariant asymmetry renews the lymphatic vasculature during homeostasis.

Connor AL, Kelley PM, Tempero RM - J Transl Med (2016)

Bottom Line: Interestingly, the morphology of tdT(+) lymphatic vasculature appeared relatively stable without significant remodeling during this time period.The results of these studies support a mechanism of invariant asymmetry to self renew the lymphatic vasculature during homeostasis.These original findings raise important questions related to the plasticity and self renewal properties that maintain the lymphatic vasculature during life.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurosensory Genetics and Otolaryngology and Head and Neck Surgery, Boys Town National Research Hospital, 555 North 30th Street, Omaha, NE, 68131, USA.

ABSTRACT

Background: The lymphatic vasculature regulates tissue physiology and immunity throughout life. The self renewal mechanism that maintains the lymphatic vasculature during conditions of homeostasis is unknown. The purpose of this study was to investigate the cellular mechanism of lymphatic endothelial cell (LEC) self renewal and lymphatic vessel maintenance.

Methods: Inductive genetic techniques were used to label LECs with tandem dimer tomato (tdT) in adult mice. Two types of studies were performed, those with high dose inductive conditions to label nearly all the lymphatic vessels and studies with low dose inductive conditions to stochastically label individual clones or small populations of LECs. We coupled image guidance techniques and live fluorescence microscopy imaging with lineage tracing to track the fate of entire tdT(+) cutaneous lymphatic vessels or the behavior of individual or small populations of LECs over 11 months. We tracked the fate of 110 LEC clones and 80 small LEC populations (clusters of 2-7 cells) over 11 months and analyzed their behavior using quantitative techniques.

Results: The results of the high dose inductive studies showed that the lymphatic vessels remained tdT(+) over 11 months, suggesting passage and expression of the tdT transgene from LEC precursors to progenies, an intrinsic model of self- renewal. Interestingly, the morphology of tdT(+) lymphatic vasculature appeared relatively stable without significant remodeling during this time period. By following the behavior of labeled LEC clones or small populations of LECs individually over 11 months, we identified diverse LEC fates of proliferation, quiescence, and extinction. Quantitative analysis of this data revealed that the average lymphatic endothelial clone or small population remained stable in size despite diverse individual fates.

Conclusion: The results of these studies support a mechanism of invariant asymmetry to self renew the lymphatic vasculature during homeostasis. These original findings raise important questions related to the plasticity and self renewal properties that maintain the lymphatic vasculature during life.

No MeSH data available.


Related in: MedlinePlus

The fate of 110 tdT+ clones was diverse despite a balanced population size. 110 tdT+ clones were identified 20 days after labeling (a), Histograms b–d show individual tdT+ clone fates at the indicated times post-labeling and the evolution of this process over 323 days. For example, at 323 post labeling, 45 clones were undetectable, 25 remained 1 cell, and 40 expanded to 2–5 cells. Analysis of the population showed that the survival or clone density decreased and stabilized over 323 days (e). Quantitative analysis showed that the average tdT+ clone size (calculated by dividing the number of total starting tdT+ clones (110)/the number of tdT+ cells at a given point in time) remained approximately one over 323 days (f). This was pooled data from 4 Lyve1CreERT2tdT mice
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Fig5: The fate of 110 tdT+ clones was diverse despite a balanced population size. 110 tdT+ clones were identified 20 days after labeling (a), Histograms b–d show individual tdT+ clone fates at the indicated times post-labeling and the evolution of this process over 323 days. For example, at 323 post labeling, 45 clones were undetectable, 25 remained 1 cell, and 40 expanded to 2–5 cells. Analysis of the population showed that the survival or clone density decreased and stabilized over 323 days (e). Quantitative analysis showed that the average tdT+ clone size (calculated by dividing the number of total starting tdT+ clones (110)/the number of tdT+ cells at a given point in time) remained approximately one over 323 days (f). This was pooled data from 4 Lyve1CreERT2tdT mice

Mentions: The fate of 110 tdT+ clones changed considerably over 323 days. tdT+ clonal extinction, quiescence, or proliferation were visualized and quantified. At the conclusion of the study 45 clones were no longer detectable (extinct). 25 clones remained as one cell (quiescence), and some clones had proliferated to become clusters of 2–5 tdT+ cells (Fig. 5a–d). Analysis of the individual tdT+ clone fates showed heterogeneous behavior over 323 days. To study the behavior of tdT+ clones as a population we used quantitative analysis. The function of tdT+ clones surviving (clone density) over time produced a death rate of 0.3 tdT+ clone/day (Fig. 5e). The average tdT+ clone size (calculated by dividing the number of total starting tdT+ clones (110)/the number of tdT+ cells at a given point in time) remained approximately 1 over 323 days (Fig. 5f). Because the average clone size was 1, we concluded that the clone proliferation and death rates were approximately equal, 0.3 tdT+ clone/day.Fig. 5


Invariant asymmetry renews the lymphatic vasculature during homeostasis.

Connor AL, Kelley PM, Tempero RM - J Transl Med (2016)

The fate of 110 tdT+ clones was diverse despite a balanced population size. 110 tdT+ clones were identified 20 days after labeling (a), Histograms b–d show individual tdT+ clone fates at the indicated times post-labeling and the evolution of this process over 323 days. For example, at 323 post labeling, 45 clones were undetectable, 25 remained 1 cell, and 40 expanded to 2–5 cells. Analysis of the population showed that the survival or clone density decreased and stabilized over 323 days (e). Quantitative analysis showed that the average tdT+ clone size (calculated by dividing the number of total starting tdT+ clones (110)/the number of tdT+ cells at a given point in time) remained approximately one over 323 days (f). This was pooled data from 4 Lyve1CreERT2tdT mice
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4940917&req=5

Fig5: The fate of 110 tdT+ clones was diverse despite a balanced population size. 110 tdT+ clones were identified 20 days after labeling (a), Histograms b–d show individual tdT+ clone fates at the indicated times post-labeling and the evolution of this process over 323 days. For example, at 323 post labeling, 45 clones were undetectable, 25 remained 1 cell, and 40 expanded to 2–5 cells. Analysis of the population showed that the survival or clone density decreased and stabilized over 323 days (e). Quantitative analysis showed that the average tdT+ clone size (calculated by dividing the number of total starting tdT+ clones (110)/the number of tdT+ cells at a given point in time) remained approximately one over 323 days (f). This was pooled data from 4 Lyve1CreERT2tdT mice
Mentions: The fate of 110 tdT+ clones changed considerably over 323 days. tdT+ clonal extinction, quiescence, or proliferation were visualized and quantified. At the conclusion of the study 45 clones were no longer detectable (extinct). 25 clones remained as one cell (quiescence), and some clones had proliferated to become clusters of 2–5 tdT+ cells (Fig. 5a–d). Analysis of the individual tdT+ clone fates showed heterogeneous behavior over 323 days. To study the behavior of tdT+ clones as a population we used quantitative analysis. The function of tdT+ clones surviving (clone density) over time produced a death rate of 0.3 tdT+ clone/day (Fig. 5e). The average tdT+ clone size (calculated by dividing the number of total starting tdT+ clones (110)/the number of tdT+ cells at a given point in time) remained approximately 1 over 323 days (Fig. 5f). Because the average clone size was 1, we concluded that the clone proliferation and death rates were approximately equal, 0.3 tdT+ clone/day.Fig. 5

Bottom Line: Interestingly, the morphology of tdT(+) lymphatic vasculature appeared relatively stable without significant remodeling during this time period.The results of these studies support a mechanism of invariant asymmetry to self renew the lymphatic vasculature during homeostasis.These original findings raise important questions related to the plasticity and self renewal properties that maintain the lymphatic vasculature during life.

View Article: PubMed Central - PubMed

Affiliation: Department of Neurosensory Genetics and Otolaryngology and Head and Neck Surgery, Boys Town National Research Hospital, 555 North 30th Street, Omaha, NE, 68131, USA.

ABSTRACT

Background: The lymphatic vasculature regulates tissue physiology and immunity throughout life. The self renewal mechanism that maintains the lymphatic vasculature during conditions of homeostasis is unknown. The purpose of this study was to investigate the cellular mechanism of lymphatic endothelial cell (LEC) self renewal and lymphatic vessel maintenance.

Methods: Inductive genetic techniques were used to label LECs with tandem dimer tomato (tdT) in adult mice. Two types of studies were performed, those with high dose inductive conditions to label nearly all the lymphatic vessels and studies with low dose inductive conditions to stochastically label individual clones or small populations of LECs. We coupled image guidance techniques and live fluorescence microscopy imaging with lineage tracing to track the fate of entire tdT(+) cutaneous lymphatic vessels or the behavior of individual or small populations of LECs over 11 months. We tracked the fate of 110 LEC clones and 80 small LEC populations (clusters of 2-7 cells) over 11 months and analyzed their behavior using quantitative techniques.

Results: The results of the high dose inductive studies showed that the lymphatic vessels remained tdT(+) over 11 months, suggesting passage and expression of the tdT transgene from LEC precursors to progenies, an intrinsic model of self- renewal. Interestingly, the morphology of tdT(+) lymphatic vasculature appeared relatively stable without significant remodeling during this time period. By following the behavior of labeled LEC clones or small populations of LECs individually over 11 months, we identified diverse LEC fates of proliferation, quiescence, and extinction. Quantitative analysis of this data revealed that the average lymphatic endothelial clone or small population remained stable in size despite diverse individual fates.

Conclusion: The results of these studies support a mechanism of invariant asymmetry to self renew the lymphatic vasculature during homeostasis. These original findings raise important questions related to the plasticity and self renewal properties that maintain the lymphatic vasculature during life.

No MeSH data available.


Related in: MedlinePlus