Modulation of thymocyte development by estrogen and autoimmune hepatitis

在芳香酶缺陷的小鼠中，胸腺退化和细胞减少是明显的。胸腺细胞发育的主要困难在皮质-髓质交界处的CD44~CD25^阶段和被膜下区域的CD44~CD25^阶段。在双阴性细胞中，Hedgehog信号的平滑表达增强。这种增强可能导致CD44^-CD25^-细胞向CD4^CD8^双阳性阶段进展受阻，并使CD4^CD8^双阳性细胞的增殖受阻。这可能是ARKO小鼠胸腺细胞成熟后期CD3、TCR、β、高GT；细胞比例降低的原因。

Thymic regression and reduced cellularity were evident in aromatase-deficient mice. The major difficulties in thymocyte development were observed during the CD44^+CD25^- stage at the cortico-medullary junction and during the CD44^-CD25^- stage at the subcapsular region. The expression of Smoothened of the Hedgehog signaling was enhanced in CD4^-CD8^- double negative cells. This enhancement may result in impaired progression of CD44^-CD25^- cells to the CD4^+CD8^+ double positive stage and impaired proliferation of CD4^+CD8^+ double positive cells. This could be the reason why the proportion of CD3^+TCRβ^<high> cells during the late phase of thymocyte maturation was reduced in ArKO mice.