Thymus Development - Revision history

Z8600021 at 05:15, 23 Ocak 2020

2020-01-23T05:15:48Z

← Older revision		Revision as of 15:15, 23 Ocak 2020
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	===Articles===		===Articles===
			{{#pmid:31505755}}

	{{#pmid:30476234}}		{{#pmid:30476234}}

Z8600021 at 22:19, 19 November 2019

2019-11-19T22:19:29Z

← Older revision		Revision as of 08:19, 20 November 2019
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	* '''{{Hox}} genes in the pharyngeal region: how Hoxa3 controls early embryonic development of the pharyngeal organs'''{{#pmid:30604847\|PMID30604847}} "The pharyngeal organs, namely the {{thyroid}}, {{thymus}}, {{parathyroid}}s, and ultimobranchial bodies, derive from the pharyngeal {{endoderm}} during embryonic development. The pharyngeal region is a segmented structure comprised of a series of reiterated structures: the pharyngeal arches on the exterior surface, the pharyngeal pouches on the interior, and a mesenchymal core. It is well known that {{Hox}} genes control spatial identity along the anterior-posterior axis of the developing vertebrate embryo, and nowhere is this is more evident than in the pharyngeal region. Each of the distinct segmented regions has a unique pattern of Hox expression, which conveys crucial positional information to the cells and tissues within it. In the context of pharyngeal organ development, molecular data suggest that HOXA3 is responsible for specifying organ identity within the third pharyngeal pouch, and in its absence, {{thymus}} and {{parathyroid}} organogenesis fails to proceed normally"		* '''{{Hox}} genes in the pharyngeal region: how Hoxa3 controls early embryonic development of the pharyngeal organs'''{{#pmid:30604847\|PMID30604847}} "The pharyngeal organs, namely the {{thyroid}}, {{thymus}}, {{parathyroid}}s, and ultimobranchial bodies, derive from the pharyngeal {{endoderm}} during embryonic development. The pharyngeal region is a segmented structure comprised of a series of reiterated structures: the pharyngeal arches on the exterior surface, the pharyngeal pouches on the interior, and a mesenchymal core. It is well known that {{Hox}} genes control spatial identity along the anterior-posterior axis of the developing vertebrate embryo, and nowhere is this is more evident than in the pharyngeal region. Each of the distinct segmented regions has a unique pattern of Hox expression, which conveys crucial positional information to the cells and tissues within it. In the context of pharyngeal organ development, molecular data suggest that HOXA3 is responsible for specifying organ identity within the third pharyngeal pouch, and in its absence, {{thymus}} and {{parathyroid}} organogenesis fails to proceed normally"

	* ''Dynamic regulation of {{~~NOTCH~~}}~~1 activation and Notch~~ ligand expression in human thymus development'' {{#pmid:30042180\|PMID30042180}} "T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced in vivo in CD34+ progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development."		* ''Dynamic regulation of NOTCH1 activation and {{Notch}} ligand expression in human thymus development'' {{#pmid:30042180\|PMID30042180}} "T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced in vivo in CD34+ progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development."

	* '''Implications for thymus growth in childhood: histogenesis of cortex and medulla'''{{#pmid:30155680\|PMID30155680}} "The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development, studies on the pre-/post-natal development of this organ and T lymphocytes in human and other species are of special interest. During our screening studies we observed structures that had not been described or mentioned previously, and named them "epitheliostromal sheaths". Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules), which the authors consider as markers of histogenesis and the growth of the organ during early childhood; these findings are thus presented to researchers in this field."		* '''Implications for thymus growth in childhood: histogenesis of cortex and medulla'''{{#pmid:30155680\|PMID30155680}} "The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development, studies on the pre-/post-natal development of this organ and T lymphocytes in human and other species are of special interest. During our screening studies we observed structures that had not been described or mentioned previously, and named them "epitheliostromal sheaths". Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules), which the authors consider as markers of histogenesis and the growth of the organ during early childhood; these findings are thus presented to researchers in this field."

Z8600021 at 22:14, 19 November 2019

2019-11-19T22:14:51Z

← Older revision		Revision as of 08:14, 20 November 2019
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	* ''Dynamic regulation of ~~NOTCH1~~ activation and Notch ligand expression in human thymus development'' {{#pmid:30042180\|PMID30042180}} "T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced in vivo in CD34+ progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development."		* '''{{Hox}} genes in the pharyngeal region: how Hoxa3 controls early embryonic development of the pharyngeal organs'''{{#pmid:30604847\|PMID30604847}} "The pharyngeal organs, namely the {{thyroid}}, {{thymus}}, {{parathyroid}}s, and ultimobranchial bodies, derive from the pharyngeal {{endoderm}} during embryonic development. The pharyngeal region is a segmented structure comprised of a series of reiterated structures: the pharyngeal arches on the exterior surface, the pharyngeal pouches on the interior, and a mesenchymal core. It is well known that {{Hox}} genes control spatial identity along the anterior-posterior axis of the developing vertebrate embryo, and nowhere is this is more evident than in the pharyngeal region. Each of the distinct segmented regions has a unique pattern of Hox expression, which conveys crucial positional information to the cells and tissues within it. In the context of pharyngeal organ development, molecular data suggest that HOXA3 is responsible for specifying organ identity within the third pharyngeal pouch, and in its absence, {{thymus}} and {{parathyroid}} organogenesis fails to proceed normally"

			* ''Dynamic regulation of {{NOTCH}}1 activation and Notch ligand expression in human thymus development'' {{#pmid:30042180\|PMID30042180}} "T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced in vivo in CD34+ progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development."

	* '''Implications for thymus growth in childhood: histogenesis of cortex and medulla'''{{#pmid:30155680\|PMID30155680}} "The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development, studies on the pre-/post-natal development of this organ and T lymphocytes in human and other species are of special interest. During our screening studies we observed structures that had not been described or mentioned previously, and named them "epitheliostromal sheaths". Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules), which the authors consider as markers of histogenesis and the growth of the organ during early childhood; these findings are thus presented to researchers in this field."		* '''Implications for thymus growth in childhood: histogenesis of cortex and medulla'''{{#pmid:30155680\|PMID30155680}} "The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development, studies on the pre-/post-natal development of this organ and T lymphocytes in human and other species are of special interest. During our screening studies we observed structures that had not been described or mentioned previously, and named them "epitheliostromal sheaths". Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules), which the authors consider as markers of histogenesis and the growth of the organ during early childhood; these findings are thus presented to researchers in this field."

Z8600021 at 05:21, 8 November 2019

2019-11-08T05:21:46Z

← Older revision		Revision as of 15:21, 8 November 2019
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	===Reviews===		===Reviews===
			{{#pmid:30927993}}

	{{#pmid:27378598}}		{{#pmid:27378598}}

Z8600021 at 01:38, 18 July 2019

2019-07-18T01:38:24Z

← Older revision		Revision as of 11:38, 18 July 2019
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	These features are named after [[:File:Arthur Hill Hassall.jpg\|Arthur Hill Hassall]] (1817-1894) a British physician and chemist who first identified these regions in 1849.<ref name=Hassall1849>{{Ref-Hassall1849}}</ref>		These features are named after [[:File:Arthur Hill Hassall.jpg\|Arthur Hill Hassall]] (1817-1894) a British physician and chemist who first identified these regions in 1849.<ref name=Hassall1849>{{Ref-Hassall1849}}</ref>

			Hassall’s Corpuscle Fetal Thymus ({{GA}} week 20)

			[[File:Thymus histology 05.jpg\|300px]]

	===Human Development===		===Human Development===

Z8600021 at 01:31, 18 July 2019

2019-07-18T01:31:59Z

← Older revision		Revision as of 11:31, 18 July 2019
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	\|}		\|}
	==Blood-Thymus Barrier==		==Blood-Thymus Barrier==
	[[File:Blood-thymus barrier EM01.jpg\|thumb\|alt=Blood-thymus barrier EM\|Blood-thymus cortical barrier EM{{#pmid:4115129\|PMID4115129}}]]		[[File:Blood-thymus barrier EM01.jpg\|thumb\|150px\|alt=Blood-thymus barrier EM\|Blood-thymus cortical barrier EM{{#pmid:4115129\|PMID4115129}}]]
	The T-lymphocytes in the thymus cortex are separated from cortical capillaries by the "blood-thymus barrier". This is a functional and selective barrier first identified in the 1960's.{{#pmid:26522647\|PMID26522647}} Venules located at the cortico-medullary junction are "leaky" for blood antigens, while the capillaries draining the cortex are largely impermeable~~. The barrier is structurally formed by both reticular cells and macrophages surrounding the cortical blood vessels~~.		The T-lymphocytes in the thymus cortex are separated from cortical capillaries by the "blood-thymus barrier". This is a functional and selective barrier first identified in the 1960's.{{#pmid:26522647\|PMID26522647}} Venules located at the cortico-medullary junction are "leaky" for blood antigens, while the capillaries draining the cortex are largely impermeable.


			The barrier is structurally formed by both epithelioreticular (reticular) cells and macrophages surrounding the cortical blood vessels.

			Barrier layers: capillary endothelium - endothelial basal lamina - perivascular CT sheath - basal lamina of epithelioreticular cells - epithelioreticular cell sheath

	==Hassall’s Corpuscles==		==Hassall’s Corpuscles==

Z8600021 at 01:28, 18 July 2019

2019-07-18T01:28:29Z

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	{{Thymus Movie 1}}		{{Thymus Movie 1}}
	\|}		\|}
			==Blood-Thymus Barrier==
			[[File:Blood-thymus barrier EM01.jpg\|thumb\|alt=Blood-thymus barrier EM\|Blood-thymus cortical barrier EM{{#pmid:4115129\|PMID4115129}}]]
			The T-lymphocytes in the thymus cortex are separated from cortical capillaries by the "blood-thymus barrier". This is a functional and selective barrier first identified in the 1960's.{{#pmid:26522647\|PMID26522647}} Venules located at the cortico-medullary junction are "leaky" for blood antigens, while the capillaries draining the cortex are largely impermeable. The barrier is structurally formed by both reticular cells and macrophages surrounding the cortical blood vessels.



	==Hassall’s Corpuscles==		==Hassall’s Corpuscles==

Z8600021 at 01:07, 14 February 2019

2019-02-14T01:07:51Z

← Older revision		Revision as of 11:07, 14 February 2019
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	* ''~~'Implications for thymus growth in childhood: histogenesis~~ of ~~cortex~~ and ~~medulla'~~''{{#pmid:~~30155680~~\|~~PMID30155680~~}} "The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development~~, studies~~ on ~~the pre~~-~~/post-natal development of this organ and T lymphocytes in human and other species are of special interest~~. ~~During our screening studies we observed structures~~ that ~~had not been described or mentioned previously~~, and ~~named them "epitheliostromal sheaths"~~. ~~Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules)~~, ~~which~~ the ~~authors consider as markers of histogenesis~~ and ~~the growth~~ of the organ during early childhood; these findings are thus presented to researchers in this field. Approximately 1000 sections prepared from infantile thymic tissues of partial biopsy specimens were immunostained and ~~examined~~. ~~Specimens were taken from ten patients (with informed consent) in the age range~~ of ~~4-9 years who underwent surgery due to congenital cardiovascular anomalies but were otherwise normal. Digital images of interest were captured to describe them in detail. Determining~~ the ~~immunophenotype~~ of ~~the compartments in these newly developing lobules assisted us greatly in defining compartments and their growth order. In summary, our findings suggest a~~ niche-based thymus growth mechanism during childhood. We presented our findings, hoping to provide additional insight to researchers aiming to restore thymus function in adulthood and improve its immunological functions.		* ''Dynamic regulation of NOTCH1 activation and Notch ligand expression in human thymus development'' {{#pmid:30042180\|PMID30042180}} "T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced in vivo in CD34+ progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development."

	* ''~~Dynamic regulation~~ of ~~NOTCH1 activation~~ and ~~Notch ligand expression in human thymus development~~'' {{#pmid:~~30042180~~\|~~PMID30042180~~}} "T-cell development ~~is a complex dynamic process that relies~~ on ~~ordered stromal signals delivered to thymus~~-~~seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated~~ in ~~cortical TECs during~~ human ~~thymus ontogeny~~ and ~~involution~~. ~~Also,~~ we ~~provide the first evidence~~ that ~~NOTCH1 activation is induced in vivo in CD34+ progenitors~~ and ~~developing thymocytes at particular cortical niches of~~ the ~~human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation~~ of ~~Notch ligand expression~~, which ~~ensures~~ the ~~coordinated delivery~~ of ~~niche-specific NOTCH1 signals required for dynamic T-cell development~~."		* '''Implications for thymus growth in childhood: histogenesis of cortex and medulla'''{{#pmid:30155680\|PMID30155680}} "The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development, studies on the pre-/post-natal development of this organ and T lymphocytes in human and other species are of special interest. During our screening studies we observed structures that had not been described or mentioned previously, and named them "epitheliostromal sheaths". Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules), which the authors consider as markers of histogenesis and the growth of the organ during early childhood; these findings are thus presented to researchers in this field."

	* '''A Single-Cell Transcriptomic Atlas of Thymus Organogenesis Resolves Cell Types and Developmental Maturation'''{{#pmid:29884461\|PMID29884461}} "We characterized maturation dynamics of thymic epithelial cells in vivo, classified cell maturation state in a thymic organ culture, and revealed the intrinsic capacity of thymic epithelium to preserve transcriptional regularity despite exposure to exogenous retinoic acid. Finally, by integrating the cell atlas with human genome-wide association study (GWAS) data and autoimmune-disease-related genes, we implicated embryonic thymus-resident cells as possible participants in autoimmune disease etiologies. This resource provides a single-cell transcriptional framework for biological discovery and molecular analysis of thymus organogenesis."		* '''A Single-Cell Transcriptomic Atlas of Thymus Organogenesis Resolves Cell Types and Developmental Maturation'''{{#pmid:29884461\|PMID29884461}} "We characterized maturation dynamics of thymic epithelial cells in vivo, classified cell maturation state in a thymic organ culture, and revealed the intrinsic capacity of thymic epithelium to preserve transcriptional regularity despite exposure to exogenous retinoic acid. Finally, by integrating the cell atlas with human genome-wide association study (GWAS) data and autoimmune-disease-related genes, we implicated embryonic thymus-resident cells as possible participants in autoimmune disease etiologies. This resource provides a single-cell transcriptional framework for biological discovery and molecular analysis of thymus organogenesis."

Z8600021 at 01:06, 14 February 2019

2019-02-14T01:06:12Z

← Older revision		Revision as of 11:06, 14 February 2019
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	* ''Dynamic regulation of NOTCH1 activation and Notch ligand expression in human thymus development'' {{#pmid:30042180}} "T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced in vivo in CD34+ progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development."		* '''Implications for thymus growth in childhood: histogenesis of cortex and medulla'''{{#pmid:30155680\|PMID30155680}} "The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development, studies on the pre-/post-natal development of this organ and T lymphocytes in human and other species are of special interest. During our screening studies we observed structures that had not been described or mentioned previously, and named them "epitheliostromal sheaths". Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules), which the authors consider as markers of histogenesis and the growth of the organ during early childhood; these findings are thus presented to researchers in this field. Approximately 1000 sections prepared from infantile thymic tissues of partial biopsy specimens were immunostained and examined. Specimens were taken from ten patients (with informed consent) in the age range of 4-9 years who underwent surgery due to congenital cardiovascular anomalies but were otherwise normal. Digital images of interest were captured to describe them in detail. Determining the immunophenotype of the compartments in these newly developing lobules assisted us greatly in defining compartments and their growth order. In summary, our findings suggest a niche-based thymus growth mechanism during childhood. We presented our findings, hoping to provide additional insight to researchers aiming to restore thymus function in adulthood and improve its immunological functions.

			* ''Dynamic regulation of NOTCH1 activation and Notch ligand expression in human thymus development'' {{#pmid:30042180\|PMID30042180}} "T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced in vivo in CD34+ progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development."

	* '''A Single-Cell Transcriptomic Atlas of Thymus Organogenesis Resolves Cell Types and Developmental Maturation'''{{#pmid:29884461\|PMID29884461}} "We characterized maturation dynamics of thymic epithelial cells in vivo, classified cell maturation state in a thymic organ culture, and revealed the intrinsic capacity of thymic epithelium to preserve transcriptional regularity despite exposure to exogenous retinoic acid. Finally, by integrating the cell atlas with human genome-wide association study (GWAS) data and autoimmune-disease-related genes, we implicated embryonic thymus-resident cells as possible participants in autoimmune disease etiologies. This resource provides a single-cell transcriptional framework for biological discovery and molecular analysis of thymus organogenesis."		* '''A Single-Cell Transcriptomic Atlas of Thymus Organogenesis Resolves Cell Types and Developmental Maturation'''{{#pmid:29884461\|PMID29884461}} "We characterized maturation dynamics of thymic epithelial cells in vivo, classified cell maturation state in a thymic organ culture, and revealed the intrinsic capacity of thymic epithelium to preserve transcriptional regularity despite exposure to exogenous retinoic acid. Finally, by integrating the cell atlas with human genome-wide association study (GWAS) data and autoimmune-disease-related genes, we implicated embryonic thymus-resident cells as possible participants in autoimmune disease etiologies. This resource provides a single-cell transcriptional framework for biological discovery and molecular analysis of thymus organogenesis."

Z8600021 at 02:18, 22 Ocak 2019

2019-01-22T02:18:55Z

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	{{#pmid:21862553}}		{{#pmid:21862553}}

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	{{#pmid:18403191}}		{{#pmid:18403191}}

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	{{#9067775}}		{{#pmid:9067775}}


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	{{#pmid:11857615}}		{{#pmid:11857615}}

← Older revision		Revision as of 08:19, 20 November 2019
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	* '''{{Hox}} genes in the pharyngeal region: how Hoxa3 controls early embryonic development of the pharyngeal organs'''{{#pmid:30604847\|PMID30604847}} "The pharyngeal organs, namely the {{thyroid}}, {{thymus}}, {{parathyroid}}s, and ultimobranchial bodies, derive from the pharyngeal {{endoderm}} during embryonic development. The pharyngeal region is a segmented structure comprised of a series of reiterated structures: the pharyngeal arches on the exterior surface, the pharyngeal pouches on the interior, and a mesenchymal core. It is well known that {{Hox}} genes control spatial identity along the anterior-posterior axis of the developing vertebrate embryo, and nowhere is this is more evident than in the pharyngeal region. Each of the distinct segmented regions has a unique pattern of Hox expression, which conveys crucial positional information to the cells and tissues within it. In the context of pharyngeal organ development, molecular data suggest that HOXA3 is responsible for specifying organ identity within the third pharyngeal pouch, and in its absence, {{thymus}} and {{parathyroid}} organogenesis fails to proceed normally"		* '''{{Hox}} genes in the pharyngeal region: how Hoxa3 controls early embryonic development of the pharyngeal organs'''{{#pmid:30604847\|PMID30604847}} "The pharyngeal organs, namely the {{thyroid}}, {{thymus}}, {{parathyroid}}s, and ultimobranchial bodies, derive from the pharyngeal {{endoderm}} during embryonic development. The pharyngeal region is a segmented structure comprised of a series of reiterated structures: the pharyngeal arches on the exterior surface, the pharyngeal pouches on the interior, and a mesenchymal core. It is well known that {{Hox}} genes control spatial identity along the anterior-posterior axis of the developing vertebrate embryo, and nowhere is this is more evident than in the pharyngeal region. Each of the distinct segmented regions has a unique pattern of Hox expression, which conveys crucial positional information to the cells and tissues within it. In the context of pharyngeal organ development, molecular data suggest that HOXA3 is responsible for specifying organ identity within the third pharyngeal pouch, and in its absence, {{thymus}} and {{parathyroid}} organogenesis fails to proceed normally"

	* ''Dynamic regulation of {{~~NOTCH~~}}~~1 activation and Notch~~ ligand expression in human thymus development'' {{#pmid:30042180\|PMID30042180}} "T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced in vivo in CD34+ progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development."		* ''Dynamic regulation of NOTCH1 activation and {{Notch}} ligand expression in human thymus development'' {{#pmid:30042180\|PMID30042180}} "T-cell development is a complex dynamic process that relies on ordered stromal signals delivered to thymus-seeding progenitors that migrate throughout different thymus microenvironments (TMEs). ... We further show that Notch ligand expression, particularly DLL4, is tightly regulated in cortical TECs during human thymus ontogeny and involution. Also, we provide the first evidence that NOTCH1 activation is induced in vivo in CD34+ progenitors and developing thymocytes at particular cortical niches of the human fetal and postnatal thymus. Collectively, our results show that human thymopoiesis involves complex spatiotemporal regulation of Notch ligand expression, which ensures the coordinated delivery of niche-specific NOTCH1 signals required for dynamic T-cell development."

	* '''Implications for thymus growth in childhood: histogenesis of cortex and medulla'''{{#pmid:30155680\|PMID30155680}} "The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development, studies on the pre-/post-natal development of this organ and T lymphocytes in human and other species are of special interest. During our screening studies we observed structures that had not been described or mentioned previously, and named them "epitheliostromal sheaths". Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules), which the authors consider as markers of histogenesis and the growth of the organ during early childhood; these findings are thus presented to researchers in this field."		* '''Implications for thymus growth in childhood: histogenesis of cortex and medulla'''{{#pmid:30155680\|PMID30155680}} "The increase in autoimmune diseases in recent years has drawn attention back to the thymus, with new approaches to improve and/or restore immune function being investigated. As the primary lymphoid organ responsible for functional T cell development, studies on the pre-/post-natal development of this organ and T lymphocytes in human and other species are of special interest. During our screening studies we observed structures that had not been described or mentioned previously, and named them "epitheliostromal sheaths". Associated with these unique structures were also small attached lobules (possibly reflecting the maturational stages of thymic lobules), which the authors consider as markers of histogenesis and the growth of the organ during early childhood; these findings are thus presented to researchers in this field."