OncoImmunology | |
Reduction of CD11b+ myeloid suppressive cells augments anti-neuroblastoma immune response induced by the anti-GD2 antibody ch14.18/CHO | |
Leon von Lojewski1  Sascha Troschke-Meurer1  Holger N. Lode1  Nikolai Siebert1  Maxi Zumpe1  Madlen Marx1  | |
[1] University Medicine Greifswald; | |
关键词: neuroblastoma; immunotherapy; ch14.18/cho; cd11b; suppressive myeloid cells; 5-fu; | |
DOI : 10.1080/2162402X.2020.1836768 | |
来源: DOAJ |
【 摘 要 】
Neuroblastoma (NB) still remains a major challenge in pediatric oncology. We recently showed CD11b+-dependent upregulation of the PD-1/PD-L1 checkpoint on NB cells treated with the chimeric anti-GD2 antibody (Ab) ch14.18/CHO. Here, we report effects of reduction of CD11b+ myeloid suppressive cells on ch14.18/CHO immunotherapy against NB. Flow cytometry, immunohistochemistry and RT-PCR were used to assess tumor infiltrating leukocytes and expression of myeloid suppressive cell-associated genes. XTT assay was used to show impact of 5-FU on tumor and effector cells. Antitumor effects of the combined treatment with ch14.18/CHO and reduction of myeloid suppressive cells were evaluated in a syngeneic NB mouse model. Tumor tissue of untreated mice showed a strong infiltration by CD11b+ cells (53% of all tumor infiltrating leukocytes). RT-PCR analysis of tumors revealed strong expression of the myeloid suppressive cell-associated genes analyzed with the strongest induction of M-CSFr, CCL2, IL-1β, IL-4, IL-6 r, IL-8, Arg1, and NOS2. Compared to controls, application of anti-CD11b Ab resulted in reduction of both CD11b+ cells in tumors and expression of myeloid suppressive cell-associated genes as well as delayed tumor growth and prolonged survival. These effects could be further improved by 5-FU. Importantly, the combinatorial immunotherapy with ch14.18/CHO and 5-FU showed the strongest antitumor effects and superior survival rates. In conclusion, reduction of immune suppressive myeloid cells augments anti-NB efficacy of a ch14.18/CHO-based immunotherapy representing a new effective treatment strategy against GD2-positive cancers.
【 授权许可】
Unknown