目的：证实人脑脉络丛内砂粒体的组成成分。方法：采用ＡＢＣ法对１例尸检的脉络丛组织进行ＴｙｐｅⅠ、Ⅲ、Ⅳ、Ⅴ、Ⅵ胶原和ｖｉｍｅｎｔｉｎ免疫组织化学检测。结果：ＴｙｐｅⅢ胶原在大量增生的胶原纤维、砂粒体的外层，未形成砂粒体的部分以及透明变的毛细血管壁呈强阳性表达。ＴｙｐｅⅥ胶原呈轻度阳性表达。ＴｙｐｅⅠ和Ⅴ胶原在少许部分呈弱阳性表达。ＴｙｐｅⅣ胶原阴性。ｖｉｍｅｎｔｉｎ在间质的纤维母细胞，血管内皮细胞和血管壁平滑肌阳性表达，而在砂粒体和透明变的毛细血管壁呈阴性表达。结论：首次报道人脑脉络丛内砂粒体的形成是来自纤维性胶原（以ＴｙｐｅⅢ胶原为主）的增生，变性和坏死所致 Objective: To confirm the composition of the sand body in the choroid plexus. Methods: The type Ⅰ, Ⅲ, Ⅳ, Ⅴ, Ⅵ collagen and vimentin immunohistochemistry were detected by ABC method in one autopsy choroid plexus. Results: TypeⅢcollagen showed strong positive expression in the hyperplastic collagen fibers, the outer layer of sand body, the non-sand body part and the transparent capillary wall. Type Ⅵ collagen was mildly positive expression. Type I and V collagens were weakly positive in a few parts. Type IV collagen negative. Vimentin was positively expressed in interstitial fibroblasts, vascular endothelial cells and vascular smooth muscle, but negatively expressed in the sagittal and transmural capillary walls. Conclusions: It was first reported that the formation of sand bodies in human choroid plexus is caused by the proliferation, degeneration and necrosis of fibrous collagen (mainly Type Ⅲ collagen)