Davenport W D, Allen E R
Department of Oral Pathology, Louisiana State University Medical Center, Schools of Dentistry and Medicine, New Orleans 70119.
Anat Rec. 1995 Feb;241(2):155-62. doi: 10.1002/ar.1092410203.
The immunological role played by the avian bursa of Fabricius has been well established. Although numerous studies have also reported on the development and general morphology of this organ, some structure-function relationships still have not been fully explained.
Bursae from chickens at three developmental stages were removed and examined by scanning electron microscopy. Routine preparation was used as well as sonication (microdissection). Micrographs were used for qualitative morphological study and for quantitative morphometric analyses.
Routine SEM observations were similar to those previously reported in the literature. Sonicated specimens allowed topographical study of various levels of surface erosion. Two types of surface cells were observed: typical absorptive epithelium and follicle-associated epithelial (FAE) cells. Erosion of the dome surface epithelium revealed basal lamina pores in the region over the subepithelial lymphoid follicles. These pores were present at hatching. Morphometric analysis of dome and pore areas revealed that the pore area decreases in relation to dome area with aging.
Basal lamina pores may provide a communication route between the lymphoid follicles and the external environment via the FAE cells. Also, the close association between the FAE cells of the epithelial domes, the epithelial pores, the capillary complex of the previously described bursal--blood barrier, and the subepithelial lymphoid follicles could represent a morphological "pore complex" that matures early in posthatching development and may be related to the immunological function of the bursa.
禽类法氏囊所发挥的免疫作用已得到充分证实。尽管众多研究也报道了该器官的发育及一般形态，但一些结构与功能的关系仍未得到充分解释。
采集处于三个发育阶段的鸡的法氏囊，通过扫描电子显微镜进行检查。采用常规制备方法以及超声处理（显微解剖）。显微照片用于定性形态学研究和定量形态计量分析。
常规扫描电镜观察结果与先前文献报道的相似。超声处理的标本能够对不同程度的表面侵蚀进行局部研究。观察到两种类型的表面细胞：典型的吸收上皮细胞和滤泡相关上皮（FAE）细胞。穹顶表面上皮的侵蚀揭示了上皮下淋巴滤泡上方区域的基膜孔。这些孔在孵化时就已存在。对穹顶和孔面积的形态计量分析表明，随着年龄增长，孔面积相对于穹顶面积减小。
基膜孔可能通过FAE细胞为淋巴滤泡与外部环境之间提供一条沟通途径。此外，上皮穹顶的FAE细胞、上皮孔、先前描述的法氏囊 - 血屏障的毛细血管复合体以及上皮下淋巴滤泡之间的紧密联系可能代表一种形态学上的“孔复合体”，它在孵化后发育早期成熟，可能与法氏囊的免疫功能有关。
