Vpliv ionizirajočega sevanja na prisotnost MHC-1 in PD-L1 v plazmalemi celic treh mišjih tumorskih celičnih linij in vitro

Maruna, Matea (author), Serša, Gregor (mentor)

Imunogenost je sposobnost tumorja, da izzove specifični imunski odziv. Imunogenost določajo biološke značilnosti tumorskih celic, to so mutacijsko breme, prisotnost kontrolnih točk imunskega odziva, kot je ligand 1 za receptor programirane celične smrti 1 (PD-L1), ter prisotnost poglavitnega kompleksa tkivne skladnosti razreda 1 (MHC-1). Vendar je imunološko razvščanje tumorjev še vedno problematično. Pokazano je bilo, da radioterapija lahko vpliva na imunogenost tumorjev. S tem namenom smo citometrično določili prisotnost MHC-1 in PD-L1 v plazmalemi živih celic pred in po izpostavitvi ionizirajočemu sevanju (6-24 Gy) in vitro. Poleg tega smo preverili in primerjali proliferacijo in radioobčutljvost celic celičnih linij B16F10, CT26 in 4T1 s pomočjo testa proliferacije in testa klonogenosti. Pokazali smo, da imajo celične linije B16F10, CT26 in 4T1 primerljive proliferacijske sposobnosti, vendar je celična linija B16F10 bolj radioobčutljiva kot celični liniji CT26 in 4T1. Pokazali smo, da je prisotnost MHC-1 statistično značilno večja v plazmalemi neobsevanih celic celične linije B16F10 (2,4 %) kot v plazmalemi neobsevanih celic celičnih linij CT26 in 4T1 (>99 %). Ionizirajoče sevanje je povečalo prisotnost MHC-1 v plazmalemi celic celične linije B16F10 pri vseh dozah obsevanja, medtem ko je ostala pri celičnih linijah CT26 in 4T1 prisotnost MHC-1 nespremenjena. Nenazadnje, pokazali smo, da pride po izpostavitvi ionizirajočemu sevanju do povečane prisotnosti PD-L1 pri vseh testiranih celičnih linijah. Zaključimo lahko, da ionizirajoče sevanje vpliva na prisotnost MHC-1 in PD-L1 v plazmalemi tumorskih celic B16F10, CT26 in 4T1.

• Language: Slovenian
• Keywords: ionizirajoče sevanje, imunogenost, mhc-1, pd-l1, proliferacija, klonogenost, in vitro
• Work type: Master's thesis/paper
• Organization: BF - Biotechnical Faculty
• Year: 2018
• PID: 20.500.12556/RUL-105244
• COBISS.SI-ID: 3052923
• Publication date in RUL: 14.11.2018

Secondary language

• Language: English
• Title: The effect of ionizing radiation on the expression of mhc-1 and pd-l1 on three murine tumor cell lines in vitro

Abstract

Immunogenicity is the ability of tumors to induce a specific immune response. It depends on different biological properties, including tumor mutational burden, the expression of immune checkpoint inhibitors such as programmed death-ligand 1 (PD-L1), and the expression of major histocompatibility complex 1 (MHC-1). The immune classification of tumors is still problematic. Studies have shown that radiotherapy can enhance tumor immunogenicity. In this study, we cytometrically determined the MHC-1 and PD-L1 expression on live cells after irradiation with doses ranging from 6 to 24 Gy in vitro. Furthermore, we tested and compared the proliferation and radiosensitivity of B16F10, CT26 and 4T1 cells using proliferation and clonogenic assays, respectively. We showed that proliferation rate of cells B16F10, CT26 and 4T1 was comparable. B16F10 cells are significantly more radiosensitive than CT26 and 4T1 cells. MHC-1 expression was significantly higher in non-irradiated CT26 and 4T1 (>99 %) cells compared to non-irradiated B16F10 cells (~2.4 %). Ionizing radiation significantly increased MHC-1 expression on B16F10 cells with all doses tested, while MHC-1 expression on CT26 and 4T1 cells remained unchanged. Moreover, PD-L1 expression was increased on B16F10, CT26 and 4T1 cells after irradiation (6-24 Gy). To conclude, our study showed that irradiation affects PD-L1 and MHC-1 expression on B16F10, 4T1 and CT26 tumor cells.

• Keywords: ionizing radiation, immunogenicity, mhc-1, pd-l1, proliferation, clonogenicity, in vitro