Anti-HPV16 E2 protein T-cell responses and viral control in women with usual vulvar intraepithelial neoplasia and their healthy partners

Hydroxychloroquine reduces T cells activation recall antigen responses

BACKGROUND

In the context of the current COVID-19 pandemic, there is still limited information about how people suffering from autoimmune diseases respond to the different COVID vaccines. The fact that they are taking an immunosuppressant or other drugs that aim to decrease the immune system activities, such as hydroxychloroquine (HCQ), could also impact their ability to respond to a COVID vaccine and vaccines in general.

METHODS

Heathy donors were given 200mg of HCQ daily for 6-weeks to assess HCQs impact on the systemic T cells and humoral immune response. Peripheral blood mononuclear cells (PBMC) and plasma were obtained at baseline and 6-weeks after starting daily HCQ. Flow cytometry assays were designed to determine changes in T cell activation and T cell responses. Bead array multiplex were used to analyse antibodies and cytokine levels before and after HCQ intake.

RESULTS

As anticipated, HCQ treatment decreased ex vivo T cell activation. We observed a decrease in CD4+CD161- expressing CCR5 (p = 0.015) and CD69 (p = 0.004) as well as in CD8+CCR5+ (p = 0.003), CD8+CD161+CCR5+ (p = 0.002) and CD8+CD161+CD95+ (p = 0.004). Additionally, HCQ decreased the proportion of Th17 expressing CD29 (p = 0.019), a subset associated with persistent inflammation. The proportion of T regulatory cells expressing the inhibitory molecule TIGIT was also reduced by HCQ (p = 0.003). As well, T cells from people on HCQ were less responsive to activation and cytokine production following stimulation with recall antigens and memory T cells were less likely to produce both IFNγ and TNFα following stimulation.

CONCLUSION

This study shows HCQ is associated with lower T cell activation and decreased T cell cytokine production. While this study was not performed with the intent of looking at COVID vaccine response, it does provide important information about the changes in immune response that may occur in patient taking HCQ as a treatment for their autoimmune disease.

Identification of HPV16 E1 and E2-specific T cells in the oropharyngeal cancer tumor microenvironment

BACKGROUND

High-risk human papillomavirus (HPV) is a primary cause of an increasing number of oropharyngeal squamous cell carcinomas (OPSCCs). The viral etiology of these cancers provides the opportunity for antigen-directed therapies that are restricted in scope compared with cancers without viral components. However, specific virally-encoded epitopes and their corresponding immune responses are not fully defined.

METHODS

To understand the OPSCC immune landscape, we conducted a comprehensive single-cell analysis of HPV16+ and HPV33+ primary tumors and metastatic lymph nodes. We used single-cell analysis with encoded peptide-human leukocyte antigen (HLA) tetramers to analyze HPV16+ and HPV33+ OPSCC tumors, characterizing the ex vivo cellular responses to HPV-derived antigens presented in major Class I and Class II HLA alleles.

RESULTS

We identified robust cytotoxic T-cell responses to HPV16 proteins E1 and E2 that were shared across multiple patients, particularly in HLA-A*01:01 and HLA-B*08:01. Responses to E2 were associated with loss of E2 expression in at least one tumor, indicating the functional capacity of these E2-recognizing T cells and many of these interactions validated in a functional assay. Conversely, cellular responses to E6 and E7 were limited in quantity and cytotoxic capacity, and tumor E6 and E7 expression persisted.

CONCLUSIONS

These data highlight antigenicity beyond HPV16 E6 and E7 and nominate candidates for antigen-directed therapies.

The presence of human papillomavirus (HPV) in placenta and/or cord blood might result in Th2 polarization

The purpose of this study was to evaluate if an early exposure to human papillomavirus (HPV) during the prenatal period or infancy could result in HPV16-specific T helper (Th) responses resembling those of adults with HPV-induced lesions. We tested HPV16-specific cell-mediated immunity (CMI) in children born with HPV-positive umbilical cord blood and/or placenta or having persistent oral HPV infection and in constantly oral HPV-negative controls. Peripheral blood mononuclear cells from 33 children from the Finnish HPV Family Study cohort (mean age 14.7 years) were stimulated with peptide pools covering the amino acid sequence of the HPV16 E2, E6, and E7 proteins. Lymphocyte proliferation, secretion of cytokines (IFN-γ, TNF-α, IL-2, IL-4, IL-5, IL-10, IL-17A), and the frequency of Foxp3+ regulatory T-cells were determined in relation to the HPV DNA status during a 14-year follow-up. 73.6% of cases and 85.7% of controls responded against HPV16 E2, while reactivity against E6 was found in 10.5 and 35.7%, respectively. The proliferative response against E6 and E7 was more frequent in controls than in cases (p = 0.047). No HPV16-specific CMI response or antibodies were detected in two children with persistent oral HPV16. The profiles of induced cytokines indicated higher levels of IL-5, IL-10, and IL-17A in children with HPV DNA in placenta and/or cord blood than in other children. HPV16-specific CMI is common in HPV DNA-negative children. The cytokine profile in children infected with HPV16 during early life suggests that the viral dose and/or specific environment created by the placenta may have significant impact on the type of HPV-specific immunity.

Immunization with Human Papillomavirus 16 L1+E2 Chimeric Capsomers Elicits Cellular Immune Response and Antitumor Activity in a Mouse Model

Development of cervical cancer is associated with persistent infections by high-risk human papillomavirus (HPV). Although current HPV L1-based prophylactic vaccines prevent infection, they do not help to eliminate prevalent infections or lesions. Our aims were (i) to generate a vaccine combining prophylactic and therapeutic properties by producing chimeric capsomers after fusion of the L1 protein to different fragments of E2 from HPV 16, and (ii) to evaluate their capacity to generate an antitumoral cellular response, while conserving L1 neutralizing epitopes. Chimeric proteins were produced in Escherichia coli and purified by glutathione S-transferase (GST)-affinity chromatography. Their structure was characterized using size exclusion chromatography, sucrose gradient centrifugation, electron microscopy, and anti-L1 enzyme-linked immunosorbent assay. All chimeric proteins form capsomers and heterogeneous aggregates. One, containing part of the carboxy-terminal domain of E2 and its hinge region (L1Δ+E2H/NC, aa 206-307), conserved the neutralizing epitope H16.V5. We then evaluated the capacity of this chimeric protein to induce a cytotoxic T-cell response against HPV 16 E2. In (51)Cr release cytotoxicity assays, splenocytes from C57BL/6 immunized mice recognized and lysed TC-1/E2 cells, which express and present endogenously processed E2 peptides. Moreover, this E2-specific cytotoxic response inhibited the growth of tumors of TC-1/E2 cells in mice. Finally, we identified an epitope (aa 292-301) of E2 involved in this cytotoxic response. We conclude that the L1Δ+E2H/NC chimeric protein produced in bacteria can be an effective and economically interesting candidate for a combined prophylactic and therapeutic vaccine that could help eliminating HPV16-positive low-grade cervical lesions and persistent viral infections, thus preventing the development of lesions and, at the same time, the establishment of new infections.

Cell mediated immunity against HPV16 E2, E6 and E7 peptides in women with incident CIN and in constantly HPV-negative women followed-up for 10-years

Background

Virus-specific cell-mediated immunity (CMI) plays a role in the outcome of genital HPV infections. To cast further light on the question why most women clear their HPV infection while others develop high-grade cervical intraepithelial neoplasia (CIN), we analyzed HPV16 E2-, E6- and E7 -specific CMI in women who developed CIN during a 10-year follow-up of the Finnish Family HPV cohort.

Methods

Overlapping 30–35 mer peptides covering the entire HPV16 E2-, E6- and E7 protein sequences were used for defining the lymphocyte proliferation capacity, cytokine production (IL-2, IL-5, IL-10, IL-17A, IFN-γ and TNF-α) and numbers of HPV16 -specific CD4+ CD25+ Foxp3+ regulatory T-cells in 10 women who developed CIN, and in 22 control women who tested constantly HPV-negative during the follow-up. HPV-specific CMI was related to the demographic data including sexual behavior, smoking and alcohol consumption.

Results

Women with CIN and their controls had similar T-cell mediated immunity against HPV16 E2, E6 and E7 peptide pools. However, nearly fourfold higher T-cell reactivity against common antigens was found in the CIN women than in the healthy donors (p = 0.001). HPV16 E6 stimulation resulted in higher IL-17A secretion in the controls than in the CIN women (p = 0.035). Smoking and use of alcohol affected the T-cell response to common antigens but not to HPV peptides (p = 0.032 and 0.045, respectively).

Conclusion

While both the CIN women and controls exhibited an HPV16-specific CMI, IL-17A might be of importance in HPV induced pathology. The hyper-responsiveness of the CIN patients to common antigens needs further studies. Smoking and alcohol had no effect on HPV-specific CMI.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0498-9) contains supplementary material, which is available to authorized users.