Carlile M J, Harrison V T, Lumsden A G, Palmer R M
Department of Dental Surgery & Periodontology, Dental School, University of Dundee, U.K.
Arch Oral Biol. 1998 May;43(5):395-406. doi: 10.1016/s0003-9969(97)00118-0.
Interpretation of results from previous tooth germ transplantation studies is limited by the inability to distinguish between donor and host cells unequivocally. Furthermore, ectopic transplantation sites have generally been used and the relevance of this to tooth development in situ is uncertain. The aim here was to determine cell fate in orthotopic tooth germ transplants using an interspecific mouse marker system. Mandibular first molar tooth germs were dissected from Mus musculus (CD1) and Mus caroli mice (age range 15-19 day embryo) and transplanted interspecifically into the alveolar crypt of extirpated first mandibular molars in neonatal M. musculus (CD1) and M. caroli hosts. Grafts were recovered at intervals up to 4 weeks postoperatively. Paraffin wax-embedded sections were examined using routine histological techniques and in situ hybridization with a biotinylated DNA probe (pmSat5) specific for M. musculus, to distinguish between donor and host cells. Development of M. musculus tooth germs in M. caroli mandibles and vice versa was similar and transplants progressed to incipient root formation. Vascularization of transplants was chimaeric, being donor-derived in the pulp and host-derived more peripherally. The investing soft tissues comprised a mixture of donor and host cells, predominantly donor. Donor cells were also found in the soft tissue of intertrabecular spaces in the surrounding bone, but alveolar osteocytes were almost entirely host-derived. Long-term survival of grafts was limited and few donor cells were present after 2 weeks. This study provides an unequivocal demonstration of the origin of all cells present in transplanted tooth germs.
以往牙胚移植研究结果的解读受到无法明确区分供体细胞和宿主细胞的限制。此外，通常使用的是异位移植部位，其与原位牙齿发育的相关性尚不确定。本研究的目的是利用种间小鼠标记系统确定原位牙胚移植中的细胞命运。从小家鼠（CD1）和卡罗小鼠（胚胎年龄范围为15 - 19天）中分离出下颌第一磨牙牙胚，并将其种间移植到新生小家鼠（CD1）和卡罗小鼠宿主中已拔除的下颌第一磨牙的牙槽窝内。术后每隔一段时间直至4周回收移植物。使用常规组织学技术和与小家鼠特异性的生物素化DNA探针（pmSat5）进行原位杂交，检查石蜡包埋切片，以区分供体细胞和宿主细胞。小家鼠牙胚在卡罗小鼠下颌骨中的发育以及反之亦然的情况相似，移植进展到初期牙根形成阶段。移植组织的血管化是嵌合的，牙髓中的血管来自供体，外周的血管来自宿主。包绕的软组织由供体细胞和宿主细胞混合组成，主要是供体细胞。在周围骨小梁间隙的软组织中也发现了供体细胞，但牙槽骨细胞几乎完全来自宿主。移植物的长期存活受到限制，2周后几乎没有供体细胞存在。这项研究明确证明了移植牙胚中所有细胞的来源。
