Department of Genetics and Bioengineering, Faculty of Engineering and Natural Sciences, Istanbul Okan University, Tuzla, 34959, Istanbul, Türkiye.
Department of Genetics and Bioengineering, Faculty of Engineering, Yeditepe University, Ataşehir, 34755, Istanbul, Türkiye.
J Endocrinol Invest. 2023 Nov;46(11):2257-2267. doi: 10.1007/s40618-023-02075-7. Epub 2023 Mar 28.
Hypoparathyroidism is a rare disease with low PTH, mostly seen as a consequence of neck surgery. Current management is the prescription of calcium and vitamin D, but the definitive treatment is parathyroid allotransplantation, which frequently triggers an immune response, thus cannot achieve the expected success. To overcome this problem, encapsulation of allogeneic cells is the most promising method. By optimizing the standard alginate cell encapsulation technique with parathyroid cells under high-voltage application, the authors reduced the size of parathyroid-encapsulated beads and evaluated these samples in vitro and in vivo.
Parathyroid cells were isolated, and standard-sized alginate macrobeads were prepared without any electrical field application, while microbeads in smaller sizes (< 500 µm), by the application of 13 kV. Bead morphologies, cell viability, and PTH secretion were evaluated in vitro for four weeks. For the in vivo part, beads were transplanted into Sprague-Dawley rats, and after retrieval, immunohistochemistry and PTH release were evaluated in addition to the assessment of cytokine/chemokine levels.
The viability of parathyroid cells in micro- and macrobeads did not differ significantly. However, the amount of in vitro PTH secretion from microencapsulated cells was significantly lower than that from macroencapsulated cells, although it increased throughout the incubation period. Immunohistochemistry of PTH staining in both of the encapsulated cells identified as positive after retrieval.
Contrary to the literature, a minimal in vivo immune response was developed for alginate-encapsulated parathyroid cells, regardless of bead size. Our findings suggest that injectable, micro-sized beads obtained using high-voltage may be a promising method for a non-surgical transplantation approach.
甲状旁腺功能减退症是一种罕见疾病，其甲状旁腺激素（PTH）水平较低，主要见于颈部手术后。目前的治疗方法是开补钙和维生素 D，但根本治疗方法是甲状旁腺同种异体移植，但该方法常引发免疫反应，因此无法达到预期的效果。为了解决这个问题，细胞的包封是最有前途的方法。作者通过在高电压应用下优化标准藻酸盐细胞包封技术，用甲状旁腺细胞制备较小尺寸(<500 µm)的微珠，并对这些样品进行了体外和体内评估。
分离甲状旁腺细胞，在没有任何电场应用的情况下制备标准大小的藻酸盐大珠，而在应用 13 kV 的情况下制备较小尺寸(<500 µm)的微珠。在体外评估了 4 周的珠形态、细胞活力和 PTH 分泌。在体内部分，将珠移植到 Sprague-Dawley 大鼠体内，在取回后，除了评估细胞因子/趋化因子水平外，还进行了免疫组织化学和 PTH 释放评估。
微珠和大珠中的甲状旁腺细胞活力没有显著差异。然而，微包封细胞体外 PTH 分泌量明显低于大包封细胞，尽管随着孵育时间的延长而增加。回收后对两种包封细胞的 PTH 染色免疫组织化学均鉴定为阳性。
与文献相反，用高压获得的藻酸盐包封甲状旁腺细胞在体内产生了最小的免疫反应，而与珠的大小无关。我们的研究结果表明，使用高压获得的可注射微珠可能是一种有前途的非手术移植方法。
