Suzuki Y, Takeda M, Farbman A I
Department of Oral Anatomy, School of Dentistry, Health Sciences University of Hokkaido, Japan.
J Comp Neurol. 1996 Dec 23;376(4):509-17. doi: 10.1002/(SICI)1096-9861(19961223)376:4<509::AID-CNE1>3.0.CO;2-5.
Macrophages are known to be phagocytes in the olfactory epithelium of adult rats. The participation of other cell types in phagocytosis in association with the cell death process was examined in the olfactory epithelium after unilateral bulbectomy of neonatal mice. The terminal deoxynucleotidyl transferase (TdT)-mediated biotinylated dUTP nick end-labeling (TUNEL) method revealed that the process of olfactory cell death consists of acute and chronic periods. The number of apoptotic cell profiles on the operated side peaked at 1 day, and the percentage of labeled cell profiles was 13.6%. The number of dying cells rapidly decreased at 3 days and decreased further at 5 days. Only 3% of the cells were labeled at 5 days. The percentage of dying cells increased again at the end of first postoperative week and remained two- to four-fold higher than control values for 2 months (4.7-5.3%). Electron micrographs of sections from early postbulbectomy stages (1-7 days) showed that as many as 30% of supporting cell profiles contained apoptotic bodies, cellular debris and phagosomes in the cytoplasm. The number of supporting cell profiles containing phagosomes declined to a plateau 2 weeks following bulbectomy and remained at 8-12% of the supporting cell population for 2 months. The results indicate that supporting cells in the olfactory epithelium play a significant role in phagocytosis in both acute and chronic of cell death after bulbectomy in newborn mice. However, supporting cells are not the exclusive phagocytic cell type in the bulbectomized epithelium; a small number of macrophages was also observed. Moreover, the phagocytosis by supporting cells was observed in unperturbed epithelium in the early stages during postnatal development.
已知巨噬细胞是成年大鼠嗅上皮中的吞噬细胞。在新生小鼠单侧嗅球切除术后，研究了嗅上皮中其他细胞类型与细胞死亡过程相关的吞噬作用。末端脱氧核苷酸转移酶（TdT）介导的生物素化dUTP缺口末端标记（TUNEL）方法显示，嗅细胞死亡过程包括急性期和慢性期。手术侧凋亡细胞轮廓数量在第1天达到峰值，标记细胞轮廓的百分比为13.6%。死亡细胞数量在第3天迅速下降，在第5天进一步下降。在第5天只有3%的细胞被标记。术后第一周结束时，死亡细胞百分比再次升高，并在2个月内比对照值高出两到四倍（4.7 - 5.3%）。嗅球切除术后早期阶段（1 - 7天）切片的电子显微镜照片显示，多达30%的支持细胞轮廓在细胞质中含有凋亡小体、细胞碎片和吞噬体。含有吞噬体的支持细胞轮廓数量在嗅球切除术后2周降至稳定水平，并在2个月内保持在支持细胞群体的8 - 12%。结果表明，嗅上皮中的支持细胞在新生小鼠嗅球切除术后细胞死亡的急性期和慢性期的吞噬作用中发挥重要作用。然而，支持细胞不是嗅球切除上皮中唯一的吞噬细胞类型；也观察到少量巨噬细胞。此外，在出生后发育早期的未受干扰的上皮中也观察到了支持细胞的吞噬作用。
