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Wnt-1 and Wnt-4 regulate thymic cellularity.

Thomas Mulroy·Jill A McMahon·Steven J Burakoff·Andrew P McMahon·Jyoti Sen
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Abstract

Thymic primordium, formed by cells derived from the endoderm, the ectoderm and the neural crest-derived mesenchyme, receive fetal liver derived lymphoid precursors. Reciprocal cell-cell interactions between thymic stromal cells and lymphoid precursors are critical in the expansion and maturation of thymocytes. Transcription factor TCF-1 is critical for the expansion of thymocytes because deletion of TCF-1 results in a significant decrease in the number of thymocytes without affecting the developmental pattern. In this report we show that Wnt-1 and Wnt-4 are expressed in the thymus and the deletion of Wnt-1 or Wnt-4 result in a substantial decrease in the number of thymocytes without affecting the pattern of maturation. Wnt-1 and Wnt-4 both regulate developing thymocytes because a double deficiency results in a significantly greater decrease of immature and mature thymocytes compared to deficiency in either Wnt-1 or Wnt-4.

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Amphibian ProteinsAnimalsCell DifferentiationCell DivisionCell SurvivalDNA, ComplementaryDNA-Binding ProteinsEgg ProteinsFetal ProteinsGenes, LethalHepatocyte Nuclear Factor 1-alphaLymphocyte CountLymphoid Enhancer-Binding Factor 1MiceMice, Inbred BALB CProtein BiosynthesisProteinsProto-Oncogene ProteinsStromal CellsT Cell Transcription Factor 1T-LymphocytesThymus GlandTranscription FactorsWnt ProteinsWnt1 ProteinWnt3 ProteinWnt4 ProteinZebrafish ProteinsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Thomas Mulroy, Jill A McMahon, Steven J Burakoff, Andrew P McMahon, Jyoti Sen. 2002. Wnt-1 and Wnt-4 regulate thymic cellularity.. https://doi.org/10.1002/1521-4141(200204)32%3A4%3C967%3A%3Aaid-immu967%3E3.0.co%3B2-6

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