Adrenocortical tissue formed by transplantation of undifferentiated cells

肾上腺皮质由形态和功能不同的肾小球带（zG）、束状带（zF）和网状带（zR）组成。最近我们在zG和zF之间发现了另一个区（未分化细胞区：zU）。;通过无法表达区域特异性甾体生成酶P450aldo和P45011β来判断，该层细胞在功能上未分化，被认为是肾上腺皮质细胞的干细胞。1999年，我们利用携带温度敏感的SV 40T抗原基因的小鼠成功建立了具有这种肾上腺皮质干细胞（AcA 101）特性的细胞系。本研究旨在探讨未分化腺皮质细胞的分化机制以及皮质区形成和维持的机制。我们在两年内（2001年和2002年）得到了以下结果。未分化细胞系AcA 101在SV40T抗原的非允许温度（39℃）和二丁基cAMP的协同作用下表达P45011β基因，并在由层粘连蛋白和胶原组成的MATRIGEL的允许温度（33℃）下表达P45011β基因。通过减法杂交，在aac101中鉴定出一个新的分泌蛋白。该蛋白包含一个分泌信号、egf样重复序列和一个蛋白水解无活性的catepsin b相关序列。mRNA及其编码蛋白仅在zU和zG中检测到，而在zF中未检测到。3 .确定该蛋白为肾上腺皮质区化因子1 （AZ-1）。有趣的是，AZ-1在肾上腺皮质细胞中的表达与p45011 β 0.5的表达呈负相关。我们曾尝试将AcA101移植到scid小鼠的肾脏中，但尚未成功获得再生组织。我们仍在研究这些细胞移植的条件。

The adrenal cortex consists of morphologically and functionally different three zones, the zona glomerulosa (zG), the zona fasciculata (zF) and the zona reticularis (zR). Recently we discovered another zone (undifferentiated cell zone : zU) between zG and zF. ; cells in the layer are functionally undifferentiated as judged by their inability to express zone-specific steroidogenic enzymes, P450aldo and P45011β, and are thought to be stem cells for adrenocortical cells. In 1999 we successfully established cell-lines exhibiting properties of such adrenocortical stem cells (AcA 101) utilizing mice carrying a temperature-sensitive SV 40T antigen gene. This study was aimed to investigate the mechanisms of differentiation of the undifferentiated adenocortical cells and the formation and maintenance of cortical zones. We obtained the following results in 2 years (2001 and 2002).1. The undifferentiated cell line (AcA 101) expressed P45011β gene at a non-permissive temperature (39℃) of SV40T antigen synergistically with exposure to dibutyryl cAMP and also at the permissive temperature (33℃) with MATRIGEL consisting of laminin and collagen IV.2. A new secretory protein was identified in AcA 101 by subtractive hybridization. The protein contained a secretory signal, EGF-like repeats, and a proteolytically inactive catepsin B-related sequence.3. The mRNA and its encoded protein were detected only in the zU and zG and not in zF., and the protein was designated as adrenocortical zonation factor 1 (AZ-1).4. Interestingly the expression of AZ-1 in adrenocortical cells is inversely correlated with expression of P45011β.5. We have tried to transplant the AcA101 to the kidney of scid mice, but we have not yet succeeded to obtain the regenerated tissues. We are still investigating the conditions for the transplantation of those cells based on the results obtained so fur.