Identification of human MHC-I HPV18 E6/E7-specific CD8 + T cell epitopes and generation of an HPV18 E6/E7-expressing adenosquamous carcinoma in HLA-A2 transgenic mice

Abstract

Background Human Papillomavirus type 18 (HPV18) is a high-risk HPV that is commonly associated with cervical cancer. HPV18 oncogenes E6 and E7 are associated with the malignant transformation of cells, thus the identification of human leukocyte antigen (HLA)-restricted E6/E7 peptide-specific CD8 + T cell epitopes and the creation of a HPV18 E6/E7 expressing cervicovaginal tumor in HLA-A2 transgenic mice will be significant for vaccine development. Methods In the below study, we characterized various human HLA class I-restricted HPV18 E6 and E7-specific CD8 + T cells mediated immune responses in HLA class I transgenic mice using DNA vaccines encoding HPV18E6 and HPV18E7. We then confirmed HLA-restricted E6/E7 specific CD8 + T cell epitopes using splenocytes from vaccinated mice stimulated with HPV18E6/E7 peptides. Furthermore, we used oncogenic DNA plasmids encoding HPV18E7E6(delD70), luciferase, cMyc, and AKT to create a spontaneous cervicovaginal carcinoma model in HLA-A2 transgenic mice. Results Therapeutic HPV18 E7 DNA vaccination did not elicit any significant CD8 + T cell response in HLA-A1, HLA-24, HLA-B7, HLA-B44 transgenic or wild type C57BL/6 mice, but it did generate a strong HLA-A2 and HLA-A11 restricted HPV18E7-specific CD8 + T cell immune response. We found that a single deletion of aspartic acid (D) at location 70 in HPV18E6 DNA abolishes the presentation of HPV18 E6 peptide (aa67-75) by murine MHC class I. We found that the DNA vaccine with this mutant HPV18 E6 generated E6-specific CD8 + T cells in HLA-A2. HLA-A11, HLA-A24 and HLA-b40 transgenic mice. Of note, HLA-A2 restricted, HPV18 E7 peptide (aa7-15)- and HPV18 E6 peptide (aa97-105)-specific epitopes are endogenously processed by HPV18 positive Hela-AAD (HLA-A*0201/Dd) cells. Finally, we found that injection of DNA plasmids encoding HPV18E7E6(delD70), AKT, cMyc, and SB100 can result in the development of adenosquamous carcinoma in the cervicovaginal tract of HLA-A2 transgenic mice. Conclusions We characterized various human HLA class I-restricted HPV18 E6/E7 peptide specific CD8 + T cell epitopes in human HLA class I transgenic mice. We demonstrated that HPV18 positive Hela cells expressing chimeric HLA-A2 (AAD) do present both HLA-A2-restricted HPV18 E7 (aa7-15)- and HPV18 E6 (aa97-105)-specific CD8 + T cell epitopes. A mutant HPV18E6 that had a single deletion at location 70 obliterates the E6 presentation by murine MHC class I and remains oncogenic. The identification of these human MHC restricted HPV antigen specific epitopes as well as the HPV18E6/E7 expressing adenosquamous cell carcinoma model may have significant future translational potential.

The role of CD4+ T cells in tumor and chronic viral immune responses

“…To exploit the cytotoxic capacity of CD8 + T cells, most of the vaccines have been designed using MHC‐I‐restricted epitopes 386,387 . However, some of the CD8 + T cell‐based vaccine strategies do not induce favorable clinical outcomes.…”

“…To exploit the cytotoxic capacity of CD8 + T cells, most of the vaccines have been designed using MHC‐I‐restricted epitopes. 386 , 387 However, some of the CD8 + T cell‐based vaccine strategies do not induce favorable clinical outcomes. For example, a CD8 + T cell‐based vaccine strategy without CD4 + T cell help cannot induce the formation of cytotoxicity in CD8 + T cells.…”

Механизмы Межклеточных Взаимодействий В Слизистой Оболочке Репродуктивного Тракта Женщин В Возрастном Аспекте

“…Воспалительное микроокружение влияет на свойства эпителиального барьера и гомеостаз слизистой оболочки, изменяя структуру и функцию эпителиальных межклеточных соединений посредством прямых и косвенных механизмов. Современное представление о сложных взаимодействиях между эпителием СОШМ и иммунными клетками в нормальной физиологической регенерации и при патологических процессах и механизмах репаративной регенерации должны опираться на лейкоцитарно-эпителиальные взаимодействия, а также на знание о медиаторах воспалительных реакций, влияющих на эпителиальный барьер и восстановление слизистой оболочки [131,150]. Расширение знаний о коммуникационных сетях между эпителием с прилежащими к нему структурами и иммунной системой приведет к тканеспецифическим стратегиям лечения патологического воспаления в системе репродуктивного тракта.…”