Oncogenic human papillomavirus could directly interact with Natural Killer cells

Poster (2012, December 10)

Oncogenic human papillomavirus could directly interact with Natural Killer cells

Poster (2012, May 04)

Human papillomavirus entry into NK cells requires CD16 expression and triggers cytotoxic activity and cytokine secretion.

in European journal of immunology (2011), 41(11), 3240-3252

Human papillomavirus (HPV) infections account for more than 50% of infection-linked cancers in women worldwide. The immune system controls, at least partially, viral infection and around 90% of HPV ... [more ▼]

Human papillomavirus (HPV) infections account for more than 50% of infection-linked cancers in women worldwide. The immune system controls, at least partially, viral infection and around 90% of HPV-infected women clear the virus within two years. However, it remains unclear which immune cells are implicated in this process and no study has evaluated the direct interaction between HPVs and NK cells, a key player in host resistance to viruses and tumors. We demonstrated an NK cell infiltration in HPV-associated pre-neoplastic cervical lesions. Since HPVs cannot grow in vitro, virus-like particles (VLPs) were used as a model for studying the NK cell response against the virus. Interestingly, NK cells displayed higher cytotoxic activity and cytokine production (TNF-alpha and IFN-gamma) in the presence of HPV-VLPs. Using flow cytometry and microscopy we observed that NK cell stimulation was linked to rapid VLP entry into these cells by macropinocytosis. Using CD16(+) and CD16(-) NK cell lines and a CD16-blocking antibody, we demonstrated that CD16 is necessary for HPV-VLP internalization, as well as for degranulation and cytokine production. Thus, we show for the first time that NK cells interact with HPVs and can participate in the immune response against HPV-induced lesions. [less ▲]

HPV triggers NK cell cytotoxic activity and cytokine secretion

Conference (2011)

Background The immune system controls, at least partially, human papillomavirus (HPV) infection and subsequent tumor development as demonstrated by a higher tumor prevalence in immunodeficient patients ... [more ▼]

Background The immune system controls, at least partially, human papillomavirus (HPV) infection and subsequent tumor development as demonstrated by a higher tumor prevalence in immunodeficient patients. Around 90% of HPV-infected women will clear the virus within two years. However, it remains unclear which immune cells are implicated in this process and no study has been performed evaluating the direct interaction between HPV and Natural Killer (NK) cells although these cells play a key role in host resistance to virus and tumor. Methods/Results By immunochemistry, we demonstrated an NK cell infiltration in HPV+ squamous pre-neoplasic lesions. Since HPV cannot grow in vitro, virus-like particles (VLP) were used as a model for studying the NK cell response against the virus. Interestingly, NK cells displayed a higher cytotoxic activity (CD107 and chromium release assays) and cytokine production (TNF-α and IFN-γ) in the presence of HPV-VLP. Uptake of HPV-VLP by dendritic cells (DC) has been shown to induce their activation, therefore, we investigated by flow cytometry and microscopy whether the stimulation of NK cell activity is linked to VLP internalization. We observed a faster entry into these cells compared to DC. Furthermore, virus uptake by NK cells is mediated by macropinocytosis, whereas this entry is dependent on clathrin or caveolin endocytosis pathways in DC. Using NK cell lines expressing or not CD16 and blocking antibody, we demonstrated that CD16 is necessary for HPV-VLP internalization, but also for degranulation and cytokine production. Conclusion Thus, we show for the first time that NK cells interact with HPV and could participate in the immune response against HPV-induced tumors. [less ▲]

Influence of the vaccine agent of uterine cervical cancer on the crosstalk between Natural Killer and Dendritic Cells

Poster (2009, November)