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Halouani A, Michaux H, Jmii H, Trussart C, Chahbi A, Martens H, Renard C, Aouni M, Hober D, Geenen V, Jaïdane H. Coxsackievirus B4 Transplacental Infection Severely Disturbs Central Tolerogenic Mechanisms in the Fetal Thymus. Microorganisms 2021; 9:microorganisms9071537. [PMID: 34361972 PMCID: PMC8303261 DOI: 10.3390/microorganisms9071537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 07/10/2021] [Accepted: 07/16/2021] [Indexed: 01/09/2023] Open
Abstract
Thymus plays a fundamental role in central tolerance establishment, especially during fetal life, through the generation of self-tolerant T cells. This process consists in T cells education by presenting them tissue-restricted autoantigens promiscuously expressed by thymic epithelial cells (TECs), thus preventing autoimmunity. Thymus infection by Coxsackievirus B (CV-B) during fetal life is supposed to disturb thymic functions and, hence, to be an inducing or accelerating factor in the genesis of autoimmunity. To further investigate this hypothesis, in our current study, we analyzed thymic expression of autoantigens, at the transcriptional and protein level, following in utero infection by CV-B4. mRNA expression levels of Igf2 and Myo7, major autoantigens of pancreas and heart, respectively, were analyzed in whole thymus and in enriched TECs together along with both transcription factors, Aire and Fezf2, involved in autoantigens expression in the thymus. Results show that in utero infection by CV-B4 induces a significant decrease in Igf2 and Myo7 expression at both mRNA and protein level in whole thymus and in enriched TECs as well. Moreover, a correlation between viral load and autoantigens expression can be observed in the whole thymus, indicating a direct effect of in utero infection by CV-B4 on autoantigens expression. Together, these results indicate that an in utero infection of the thymus by CV-B4 may interfere with self-tolerance establishment in TECs by decreasing autoantigen expression at both mRNA and protein level and thereby increase the risk of autoimmunity onset.
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Affiliation(s)
- Aymen Halouani
- Laboratoire des Maladies Transmissibles et Substances Biologiquement Actives LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir 5000, Tunisia; (A.H.); (H.J.); (M.A.)
- Faculté des Sciences de Tunis, Université de Tunis El Manar, Tunis 1068, Tunisia
- GIGA-I3 Immunoendocrinologie, Faculté de Médicine, Université de Liège, CHU-B34, Sart Tilman, 4000 Liège, Belgium; (H.M.); (C.T.); (H.M.); (C.R.); (V.G.)
| | - Hélène Michaux
- GIGA-I3 Immunoendocrinologie, Faculté de Médicine, Université de Liège, CHU-B34, Sart Tilman, 4000 Liège, Belgium; (H.M.); (C.T.); (H.M.); (C.R.); (V.G.)
| | - Habib Jmii
- Laboratoire des Maladies Transmissibles et Substances Biologiquement Actives LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir 5000, Tunisia; (A.H.); (H.J.); (M.A.)
- Faculté des Sciences de Tunis, Université de Tunis El Manar, Tunis 1068, Tunisia
| | - Charlotte Trussart
- GIGA-I3 Immunoendocrinologie, Faculté de Médicine, Université de Liège, CHU-B34, Sart Tilman, 4000 Liège, Belgium; (H.M.); (C.T.); (H.M.); (C.R.); (V.G.)
| | - Ahlem Chahbi
- Laboratoire d’Hématologie, Faculté de Médecine de Tunis, Université de Tunis El Manar, Tunis 1007, Tunisia;
| | - Henri Martens
- GIGA-I3 Immunoendocrinologie, Faculté de Médicine, Université de Liège, CHU-B34, Sart Tilman, 4000 Liège, Belgium; (H.M.); (C.T.); (H.M.); (C.R.); (V.G.)
| | - Chantal Renard
- GIGA-I3 Immunoendocrinologie, Faculté de Médicine, Université de Liège, CHU-B34, Sart Tilman, 4000 Liège, Belgium; (H.M.); (C.T.); (H.M.); (C.R.); (V.G.)
| | - Mahjoub Aouni
- Laboratoire des Maladies Transmissibles et Substances Biologiquement Actives LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir 5000, Tunisia; (A.H.); (H.J.); (M.A.)
| | - Didier Hober
- Laboratoire de Virologie EA3610, Faculté de Médecine, Université de Lille, CHU Lille, 59000 Lille, France;
| | - Vincent Geenen
- GIGA-I3 Immunoendocrinologie, Faculté de Médicine, Université de Liège, CHU-B34, Sart Tilman, 4000 Liège, Belgium; (H.M.); (C.T.); (H.M.); (C.R.); (V.G.)
| | - Hela Jaïdane
- Laboratoire des Maladies Transmissibles et Substances Biologiquement Actives LR99ES27, Faculté de Pharmacie de Monastir, Université de Monastir, Monastir 5000, Tunisia; (A.H.); (H.J.); (M.A.)
- Correspondence: ; Tel.: +216-98-677-174
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MicroRNAs Regulate Thymic Epithelium in Age-Related Thymic Involution via Down- or Upregulation of Transcription Factors. J Immunol Res 2017; 2017:2528957. [PMID: 29226156 PMCID: PMC5684555 DOI: 10.1155/2017/2528957] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Revised: 08/09/2017] [Accepted: 08/20/2017] [Indexed: 12/14/2022] Open
Abstract
Age-related thymic involution is primarily induced by defects in nonhematopoietic thymic epithelial cells (TECs). It is characterized by dysfunction of multiple transcription factors (TFs), such as p63 and FoxN1, and also involves other TEC-associated regulators, such as Aire. These TFs and regulators are controlled by complicated regulatory networks, in which microRNAs (miRNAs) act as a key player. miRNAs can either directly target the 3'-UTRs (untranslated regions) of the TFs to suppress TF expression or target TF inhibitors to reduce or increase TF inhibitor expression and thereby indirectly enhance or inhibit TF expression. Here, we review the current understanding and recent studies about how miRNAs are involved in age-related thymic involution via regulation of TEC-autonomous TFs. We also discuss potential strategies for targeting miRNAs to rejuvenate age-related declined thymic function.
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