Oyer Jeremiah L, Pandey Veethika, Igarashi Robert Y, Somanchi Srinivas S, Zakari Ahmed, Solh Melhem, Lee Dean A, Altomare Deborah A, Copik Alicja J
Burnett School of Biomedical Sciences, University of Central Florida, Orlando, Florida, USA.
Division of Pediatrics and Cell Therapy Section, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
Cytotherapy. 2016 May;18(5):653-63. doi: 10.1016/j.jcyt.2016.02.006.
Natural killer (NK) cell immunotherapy for treatment of cancer is promising, but requires methods that expand cytotoxic NK cells that persist in circulation and home to disease site.
We developed a particle-based method that is simple, effective and specifically expands cytotoxic NK cells from peripheral blood mononuclear cells (PBMCs) both ex vivo and in vivo. This method uses particles prepared from plasma membranes of K562-mb21-41BBL cells, expressing 41BBL and membrane bound interleukin-21 (PM21 particles).
Ex vivo, PM21 particles caused specific NK-cell expansion from PBMCs from healthy donors (mean 825-fold, range 163-2216, n = 13 in 14 days) and acute myeloid leukemia patients. The PM21 particles also stimulated in vivo NK cell expansion in NSG mice. Ex vivo pre-activation of PBMCs with PM21 particles (PM21-PBMC) before intraperitoneal (i.p.) injection resulted in 66-fold higher amounts of hNK cells in peripheral blood (PB) of mice compared with unactivated PBMCs on day 12 after injection. In vivo administration of PM21 particles resulted in a dose-dependent increase of PB hNK cells in mice injected i.p. with 2.0 × 10(6) PM21-PBMCs (11% NK cells). Optimal dose of 800 µg/injection of PM21 particles (twice weekly) with low-dose interleukin 2 (1000 U/thrice weekly) resulted in 470 ± 40 hNK/µL and 95 ± 2% of total hCD45(+) cells by day 12 in PB. Furthermore, hNK cells were found in marrow, spleen, lung, liver and brain (day 16 after i.p. PM21/PBMC injection), and mice injected with PM21 particles had higher amounts.
The extent of NK cells observed in PB, their persistence and the biodistribution would be relevant for cancer treatment.
自然杀伤（NK）细胞免疫疗法在癌症治疗中前景广阔，但需要能够扩增循环中持续存在并归巢至疾病部位的细胞毒性NK细胞的方法。
我们开发了一种基于颗粒的方法，该方法简单、有效，能在体外和体内从外周血单核细胞（PBMC）中特异性扩增细胞毒性NK细胞。此方法使用由表达4-1BBL和膜结合白细胞介素-21的K562-mb21-41BBL细胞的质膜制备的颗粒（PM21颗粒）。
在体外，PM21颗粒能使健康供体（1天内平均扩增825倍，范围为163 - 2216倍，14天内n = 13）和急性髓系白血病患者的PBMC中的NK细胞特异性扩增。PM21颗粒还能刺激NSG小鼠体内的NK细胞扩增。在腹腔注射前用PM21颗粒（PM21-PBMC）对PBMC进行体外预激活，与未激活的PBMC相比，在注射后第12天小鼠外周血（PB）中的人NK细胞数量高66倍。体内给予PM21颗粒导致腹腔注射2.0×10⁶个PM21-PBMC（11%为NK细胞）的小鼠外周血hNK细胞呈剂量依赖性增加。每周两次注射800μg/次的PM21颗粒与低剂量白细胞介素2（每周三次，1000U）的最佳剂量组合，在第12天时外周血中产生470±40个hNK/μL且占总hCD45⁺细胞的95±2%。此外，在骨髓、脾脏、肺、肝脏和大脑中发现了hNK细胞（腹腔注射PM21/PBMC后第16天），注射PM21颗粒的小鼠体内hNK细胞数量更多。
在外周血中观察到的NK细胞数量、其持久性和生物分布对于癌症治疗具有重要意义。
