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Dumont-Lagacé M, Daouda T, Depoërs L, Zumer J, Benslimane Y, Brochu S, Harrington L, Lemieux S, Perreault C. Qualitative Changes in Cortical Thymic Epithelial Cells Drive Postpartum Thymic Regeneration. Front Immunol 2020; 10:3118. [PMID: 32010151 PMCID: PMC6974522 DOI: 10.3389/fimmu.2019.03118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 12/20/2019] [Indexed: 12/05/2022] Open
Abstract
During gestation, sex hormones cause a significant thymic involution which enhances fertility. This thymic involution is rapidly corrected following parturition. As thymic epithelial cells (TECs) are responsible for the regulation of thymopoiesis, we analyzed the sequential phenotypic and transcriptomic changes in TECs during the postpartum period in order to identify mechanisms triggering postpartum thymic regeneration. In particular, we performed flow cytometry analyses and deep RNA-sequencing on purified TEC subsets at several time points before and after parturition. We report that pregnancy-induced involution is not caused by loss of TECs since their number does not change during or after pregnancy. However, during pregnancy, we observed a significant depletion of all thymocyte subsets downstream of the double-negative 1 (DN1) differentiation stage. Variations in thymocyte numbers correlated with conspicuous changes in the transcriptome of cortical TECs (cTECs). The transcriptomic changes affected predominantly cTEC expression of Foxn1, its targets and several genes that are essential for thymopoiesis. By contrast, medullary TECs (mTECs) showed very little transcriptomic changes in the early postpartum regenerative phase, but seemed to respond to the expansion of single-positive (SP) thymocytes in the late phase of regeneration. Together, these results show that postpartum thymic regeneration is orchestrated by variations in expression of a well-defined subset of cTEC genes, that occur very early after parturition.
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Affiliation(s)
- Maude Dumont-Lagacé
- Immunobiology Research Unit, Department of Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| | - Tariq Daouda
- Immunobiology Research Unit, Department of Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada.,Functional and Structural Bioinformatics Research Unit, Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| | - Lucyle Depoërs
- Immunobiology Research Unit, Department of Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| | - Jérémie Zumer
- Functional and Structural Bioinformatics Research Unit, Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| | - Yahya Benslimane
- Telomere Length Homeostasis and Genomic Instability Research Unit, Department of Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| | - Sylvie Brochu
- Immunobiology Research Unit, Department of Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| | - Lea Harrington
- Telomere Length Homeostasis and Genomic Instability Research Unit, Department of Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| | - Sébastien Lemieux
- Functional and Structural Bioinformatics Research Unit, Department of Biochemistry and Molecular Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
| | - Claude Perreault
- Immunobiology Research Unit, Department of Medicine, Institute for Research in Immunology and Cancer, Université de Montréal, Montréal, QC, Canada
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Brown GP, Shine R. Maternal body size influences offspring immune configuration in an oviparous snake. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160041. [PMID: 27069670 PMCID: PMC4821281 DOI: 10.1098/rsos.160041] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 02/16/2016] [Indexed: 06/05/2023]
Abstract
Like most ectothermic vertebrates, keelback snakes (Tropidonophis mairii) do not exhibit parental care. Thus, offspring must possess an immune system capable of dealing with challenges such as pathogens, without assistance from an attendant parent. We know very little about immune system characteristics of neonatal reptiles, including the magnitude of heritability and other maternal influences. To identify sources of variation in circulating white blood cell (WBC) concentrations and differentials, we examined blood smears from 246 hatchling snakes and their field-caught mothers. WBC concentrations were lower in hatchlings than in adults, and hatchlings had more basophils and fewer azurophils than adults. A hatchling keelback's WBC differential was also influenced by its sex and body size. Although hatchling WBC measures exhibited negligible heritability, they were strongly influenced by maternal body size and parasite infection (but not by maternal body condition, relative clutch mass or time in captivity). Larger mothers produced offspring with more azurophils and fewer lymphocytes. The mechanisms and consequences of WBC variation are currently unknown, but if these maternal effects enhance offspring fitness, the impact of maternal body size on reproductive success may be greater than expected simply from allometric increases in the numbers and sizes of progeny.
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Bílková B, Vinklerová J, Vinkler M. The relationship between health and cell-mediated immunity measured in ecology: Phytohaemagglutinin skin-swelling test mirrors blood cellular composition. ACTA ACUST UNITED AC 2015; 323:767-777. [DOI: 10.1002/jez.1990] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 09/03/2015] [Accepted: 09/07/2015] [Indexed: 11/10/2022]
Affiliation(s)
- Barbora Bílková
- Department of Zoology; Faculty of Science; Charles University in Prague; Viničná 7 Czech Republic
| | - Jitka Vinklerová
- Department of Zoology; Faculty of Science; Charles University in Prague; Viničná 7 Czech Republic
| | - Michal Vinkler
- Department of Zoology; Faculty of Science; Charles University in Prague; Viničná 7 Czech Republic
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