IL-17 suppresses immune effector functions in human papillomavirus-associated epithelial hyperplasia

Human papillomavirus associated cervical lesion: pathogenesis and therapeutic interventions

Human papillomavirus (HPV) is the most prevalent sexually transmitted virus globally. Persistent high-risk HPV infection can result in cervical precancerous lesions and cervical cancer, with 70% of cervical cancer cases associated with high-risk types HPV16 and 18. HPV infection imposes a significant financial and psychological burden. Therefore, studying methods to eradicate HPV infection and halt the progression of precancerous lesions remains crucial. This review comprehensively explores the mechanisms underlying HPV-related cervical lesions, including the viral life cycle, immune factors, epithelial cell malignant transformation, and host and environmental contributing factors. Additionally, we provide a comprehensive overview of treatment methods for HPV-related cervical precancerous lesions and cervical cancer. Our focus is on immunotherapy, encompassing HPV therapeutic vaccines, immune checkpoint inhibitors, and advanced adoptive T cell therapy. Furthermore, we summarize the commonly employed drugs and other nonsurgical treatments currently utilized in clinical practice for managing HPV infection and associated cervical lesions. Gene editing technology is currently undergoing clinical research and, although not yet employed officially in clinical treatment of cervical lesions, numerous preclinical studies have substantiated its efficacy. Therefore, it holds promise as a precise treatment strategy for HPV-related cervical lesions.

Nocardia rubra cell-wall skeleton activates an immune response in cervical tissue via stimulating FPR3 to enhance dendritic cell-mediated Th1 differentiation

Nocardia rubra cell wall skeleton (Nr-CWS) has proven to be a successful medicine for therapy of cervical human papillomavirus infection. The mechanism of action of Nr-CWS is unclear but may involve a stimulatory effect on the host immune system. We previously found that CD4⁺ T cells were increased in cervical tissue after Nr-CWS treatment. Microarray data from these cervical tissues revealed the significant upregulation of formylated peptide receptor 3 (FPR3). This study aimed to explore the role of Nr-CWS in immunomodulatory based on these findings. Examination of CD4⁺ T cell subsets in cervical tissue from patients who received Nr-CWS revealed substantial increases in Th1 cytokines and transcription factors. The regulatory effects of Nr-CWS on the function and phenotype of dendritic cells (DCs) were assessed in comparison with the traditional DC maturation inducer lipopolysaccharide (LPS). Similar to LPS, Nr-CWS potently induced DC maturation and interleukin-12 (IL-12) secretion. Differentiation of T cells induced by Nr-CWS stimulated DCs was assessed using the mixed lymphocyte reaction assay. Significant differentiation towards Th1 was evident. Finally, FPR3 expression in DCs in response to Nr-CWS and LPS was measured. Nr-CWS potently upregulated FPR3 expression, while the LPS did not. Silencing FPR3 in DCs reduced Nr-CWS-induced IL-12 production and Th1 cell polarization in co-cultured T cells. The collective findings indicate that Nr-CWS may target FPR3 on the surface of DC cells and activate a Th1-type immune response. The findings clarify the basis of the antiviral immune effects of Nr-CWS on human papillomavirus.

The Interplay Between Cervicovaginal Microbial Dysbiosis and Cervicovaginal Immunity

The cervicovaginal microbiota plays a key role in the health and reproductive outcomes of women. In reality epidemiological studies have demonstrated that there is an association between the structure of cervicovaginal microbiota and reproductive health, although key mechanistic questions regarding these effects remain unanswered and understanding the interplay between the immune system and the structure of the cervicovaginal microbiota. Here, we review existing literature relating to the potential mechanisms underlying the interaction between vaginal microbes and the immune system; we also describe the composition and function of the microbiome and explain the mechanisms underlying the interactions between these microbial communities and various aspects of the immune system. Finally, we also discuss the diseases that are caused by disorders of the reproductive tract and how the immune system is involved. Finally, based on the data presented in this review, the future perspectives in research directions and therapeutic opportunities are explored.

Changes of the vaginal microbiota in HPV infection and cervical intraepithelial neoplasia: a cross-sectional analysis

This study aimed to explore the changes of the vaginal microbiota and enzymes in the women with high-risk human papillomavirus (HR-HPV) infection and cervical lesions. A total of 448 participants were carried out HPV genotyping, cytology tests, and microecology tests, and 28 participants were treated as sub-samples, in which vaginal samples were characterized by sequencing the bacterial 16S V4 ribosomal RNA (rRNA) gene region. The study found the prevalence of HR-HPV was higher in patients with BV (P = 0.036). The HR-HPV infection rate was 72.73% in G. vaginalis women, which was significantly higher than that of women with lactobacillus as the dominant microbiota (44.72%) (P = 0.04). The positive rate of sialidase (SNA) was higher in women with HR-HPV infection (P = 0.004) and women diagnosed with cervical intraepithelial neoplasia (CIN) (P = 0.041). In HPV (+) women, the α-diversity was significantly higher than that in HPV (−) women. The 16S rRNA gene-based amplicon sequencing results showed that Lactobacillus was the dominant bacteria in the normal vaginal microbiota. However, the proportion of Gardnerella and Prevotella were markedly increased in HPV (+) patients. Gardnerella and Prevotella are the most high-risk combination for the development of HPV (+) women. The SNA secreted by Gardnerella and Prevotella may play a significant role in HPV infection progress to cervical lesions.

Correlation of serum interleukin 17 and macrophage migration inhibitory factor levels with clinical response to intralesional Candida antigen and their potential use as predictors of clinical outcome in patients with multiple common warts

BACKGROUND

Candida antigen injection is one of the most widely used intralesional immunotherapy in the treatment of warts. It acts through the induction of systemic immune response. The pattern of cytokines production may play an integral role in its mechanism of action.

AIM

To investigate the possible relation between serum levels of IL17 and MIF, and the clinical response to intralesional Candida antigen in multiple common warts.

METHODS

A total of 90 patients with multiple common warts were divided into 2 groups. Sixty patients received intralesional Candida antigen injection into the largest wart, controlled against thirty patients who had intralesional saline, as placebo. The injection was done at a 2-week interval for 5 doses. Blood samples were obtained from both groups, and serum levels of IL17A and MIF were estimated at baseline and 2 weeks after the last session using ELISA kits.

RESULTS

Complete clearance of warts was statistically higher in the Candida antigen group (40% of the patients) compared to the saline group (p < 0.05). The serum levels of IL17 had significantly declined from baseline, while the level of MIF had risen after intralesional Candida antigen injection, but not in the saline group. At a cutoff level of 316 pg/ml, IL17 had a sensitivity of 83.3% to predict therapeutic response.

CONCLUSION

IL17A and MIF may have possible roles in the mechanism of action of Candida antigen in the treatment of common warts. At a certain level, serum IL17A may be a potential predictor of response to treatment.

The prevalence of human papillomavirus and bacterial vaginosis among young women in China: a cross-sectional study

Background

The natural history of human papillomavirus (HPV) is influenced by vaginal microenvironment disorders, such as bacterial vaginosis (BV). The objective of this study was to assess the epidemiology of HPV combined with BV prevalence among Chinese women aged 20–35 years.

Methods

A total of 2000 sexually active women aged 20–35 years voluntarily enrolled in this study and underwent a ThinPrep cytologic test and PCR-reverse dot blot human papillomavirus genotyping (PCR-RDB HPV test). BV was diagnosed if clue cells were observed (20% more than epithelial cells).

Results

The overall HPV infection rate in this population was 16.2% (324/2000). Compared with HPV-negative individuals, BV prevalence was higher in the High-risk human papillomavirus (HR-HPV) (5.9% vs. 3.1%, P < 0.001). BV and HPV-51, -52 infection were more commonly associated with each other. In patients with cervical lesions (≥ CIN 1), the BV prevalence rate was higher than in patients with negative for intraepithelial lesion or malignancy (NILM) (11.9% vs. 3.8%, P = 0.002).

Conclusion

BV was found to be related to HPV-51, -52 infections and cervical lesions. To better manage HPV infected population, more attention should be paid to the prevention and proper treatment of BV.

Interleukin-17-A multifaceted cytokine in viral infections

Viral infections are a major threat to the human population due to the lack of selective therapeutic measures. The morbidity and mortality reported worldwide are very alarming against viral pathogens. The proinflammatory environment is required for viral inhibition by initiating the host immune response. The host immune response fights these pathogens by secreting different cytokines. Interleukin-17 (IL-17) a proinflammatory cytokine mainly produced by T helper type 17 cells, plays a vital role in the regulation of host immune response against various pathogens, including viruses. However, dysregulated production of IL-17 induces chronic inflammation, autoimmune disorders, and may lead to cancer. Recent studies suggest that IL-17 is not only involved in the antiviral immune response but also promotes virus-mediated illnesses. In this review, we discuss the protective and pathogenic role of IL-17 against various viral infections. A detailed understanding of IL-17 during viral infections could contribute to improve therapeutic measures and enable the development of an efficient and safe IL-17 based immunotherapy.

Role of interleukin-17 in human papillomavirus infection and associated malignancies

Human papillomavirus infection is among the leading viral infections in the world, causing severe mortality and morbidity. The virus mainly targets the female genital tract-cervix, vulva, anus but it is also reported to infect the lungs and oropharyngeal region of the body. The host immune response plays a vital role in the persistence of viral infection. Interleukin 17 (IL-17) is mainly secreted by Th17 cells and mediates the immune response that enhances the disease severity in HPV infection. IL-17 is reported to promote lesions and tumour progression by creating a hyperinflammatory condition leading to cancer. The current minireview summarizes the pathogenic role of IL-17 in HPV infection and HPV-induced malignancies. Further study on IL-17 associated pathology of HPV infection would be useful in developing therapeutic measures.

Secukinumab on Refractory Lupus Nephritis

Lupus nephritis (LN) is the most frequent severe organ manifestation of systemic lupus erythematosus (SLE). About 30% of patients are refractory to treatment. The authors report a case of treatment of LN with interleukin-17-targeted therapy, demonstrating its possible benefit, after reports of T helper 17 cell involvement in SLE pathogenesis.

We present the case of a childbearing age woman with SLE, who developed refractory LN despite all the indicated therapeutic options. During follow up, infection with human papillomavirus was detected, a possible trigger, and the following management was based on this discovery. We currently know that cytokines play a major role in tissue damage and interleukin-17 (IL-17) seems to be a fundamental key in SLE and LN, having shown its expression in renal glomeruli and urinary sediment. Thus, it was decided to start treatment with an anti-IL-17A antibody, secukinumab. After starting secukinumab, clinical and biological features improved and complete renal response was achieved.

Vaginal Lactobacilli and Vaginal Dysbiosis-Associated Bacteria Differently Affect Cervical Epithelial and Immune Homeostasis and Anti-Viral Defenses

Persistent infection with High Risk-Human Papilloma Viruses (HR-HPVs) is a primary cause of cervical cancer worldwide. Vaginal-dysbiosis-associated bacteria were correlated with the persistence of HR-HPVs infection and with increased cancer risk. We obtained strains of the most represented bacterial species in vaginal microbiota and evaluated their effects on the survival of cervical epithelial cells and immune homeostasis. The contribution of each species to supporting the antiviral response was also studied. Epithelial cell viability was affected by culture supernatants of most vaginal-dysbiosis bacteria, whereas Lactobacillus gasseri or Lactobacillus jensenii resulted in the best stimulus to induce interferon-γ (IFN-γ) production by human mononuclear cells from peripheral blood (PBMCs). Although vaginal-dysbiosis-associated bacteria induced the IFN-γ production, they were also optimal stimuli to interleukin-17 (IL-17) production. A positive correlation between IL-17 and IFN-γ secretion was observed in cultures of PBMCs with all vaginal-dysbiosis-associated bacteria suggesting that the adaptive immune response induced by these strains is not dominated by T_H1 differentiation with reduced availability of IFN-γ, cytokine most effective in supporting virus clearance. Based on these results, we suggest that a vaginal microbiota dominated by lactobacilli, especially by L. gasseri or L. jensenii, may be able to assist immune cells with clearing HPV infection, bypasses the viral escape and restores immune homeostasis.

Cytokine response following perturbation of the cervicovaginal milieu during HPV genital infection

Human papillomaviruses (HPVs) are oncogenic viruses causing most cervical cancers. Highly prevalent in young, sexually active women, only a minority of HPV infections persist. To better characterize the immuno-modulatory impact of early HPV infections, we measured changes in a panel of 20 cytokines in cervicovaginal samples collected from young women who were tested for HPV and self-reported for genital inflammation and infection symptoms. Multi-factor statistical analyses revealed that increased IL-1Alpha and IL-12/IL-23p40 concentrations were associated with HPV infection and that macrophage inflammatory proteins were associated in particular with high-risk HPV infections. ClinicalTrials.gov identifier NCT02946346.

In situ immunopathological events in human cervical intraepithelial neoplasia and cervical cancer: Review

Neoplasia of the cervix represents one of the most common cancers in women. Clinical and molecular research has identified immunological impairment in squamous intraepithelial cervical lesions and cervical cancer patients. The in-situ expression of several cytokines by uterine epithelial cells and by infiltrating leukocytes occurs during the cervical intraepithelial neoplasia and cervical cancer. Some of these cytokines can prevent and others can induce the progression of the neoplasm. The infiltrating leukocytes also produce cytokines and growth factors relate to angiogenesis, chemotaxis, and apoptosis capable of modulating the dysplasia progression. In this review we analyzed several interleukins with an inductive effect or blocking effect on the neoplastic progression. We also analyze the genetic polymorphism of some cytokines and their relationship with the risk of developing cervical neoplasia. In addition, we describe the leukocyte cells that infiltrate the cervical uterine tissue during the neoplasia and their effects on neoplasia progression.

Therapeutic DNA Vaccine Against HPV16-Associated Cancer

Human papillomavirus (HPV) is a contagious cause of anogenital and oropharyngeal cancers developing from persistently infected and subsequently transformed basal keratinocytes of mucosal epithelium. DNA-based immunotherapy offers great potential for the treatment of persisting HPV infections and associated cancers. Preclinical testing of therapeutic DNA-based HPV-targeted immunotherapy requires robust animal models which mimic HPV-associated cancer disease in humans. Here we describe a detailed protocol of intradermal delivery of a therapeutic DNA vaccine and a grafting model of neoantigen expressing skin to evaluate vaccine efficacy against HPV16 mediated hyperproliferative epithelium in mice.

Regulatory T Cells but Not IL-10 Impair Cell-Mediated Immunity in Human Papillomavirus E7+ Hyperplastic Epithelium

High-risk human papillomavirus infection can induce cervical and other intraepithelial neoplasia and invasive cancers. A transgenic mouse expressing keratin 14 promotor-driven HPV16 E7 oncoprotein exhibits epithelial hyperplasia and mimics many features of human papillomavirus-related intraepithelial precancers. We have previously demonstrated that HPV16 E7-mediated epithelial hyperplasia suppresses T helper type 1 responses to intradermally delivered antigen and directs differentiation of CD4⁺ T cells towards a Foxp3⁺ regulatory phenotype (Treg). Here we establish that Foxp3⁺ Treg expansion from a transferred naive T-cell population is driven directly by the hyperplastic skin and is independent of pre-existing immune-modulated lymphocytes. However, depletion of endogenous CD25⁺ Tregs before priming of adoptively transferred T cells significantly improves antigen-specific CD8⁺ T-cell responses but not T helper type 1 responses. Deletion of IL-10 had no effect on Treg expansion, epidermal dendritic cell alteration, and suppression of induced T helper type 1 immunity in HPV16 E7-driven hyperplastic mice. Thus, HPV16 E7-mediated epithelial hyperplasia promotes expansion of peripheral Tregs in response to intradermal immunization that suppress antigen-specific CD8⁺ T-cell responses independently of IL-10, but depletion of these Tregs is not sufficient to restore T helper type 1 immunity.

Equine Penile Squamous Cell Carcinomas as a Model for Human Disease: A Preliminary Investigation on Tumor Immune Microenvironment

Penile squamous cell carcinomas (SCCs) are common tumors in older horses, with poor prognosis mostly due to local invasion and recurrence. These tumors are thought to be mainly caused by Equus caballus papillomavirus type 2 (EcPV-2). The aim of this study is to characterize the tumor immune environment (TIME) in equine penile tumors. Equine penile epithelial tumors (17 epSCCs; 2 carcinomas in situ, CIS; 1 papilloma, P) were retrospectively selected; immune infiltrate was assessed by histology and immunohistochemistry; RT-qPCR tested the expression of selected chemokines and EcPV-2 DNA and RNA. The results confirmed EcPV-2-L1 DNA in 18/20 (90%) samples. L1 expression was instead retrieved in 13/20 cases (65%). The samples showed an increased infiltration of CD3⁺lymphocytes, macrophages (MAC387; IBA1), plasma cells (MUM1), and FoxP3⁺lymphocytes in the intra/peritumoral stroma when compared to extratumoral tissues (p < 0.05). Only MAC387⁺neutrophils were increased in EcPV-2^high viral load samples (p < 0.05). IL12/p35 was differentially expressed in EcPV^high and EcPV^low groups (p = 0.007). A significant decrease of IFNG and IL2 expression was highlighted in TGFB1-positive samples (p < 0.05). IBA1 and CD20 were intratumorally increased in cases where IL-10 was expressed (p < 0.005). EpSCCs may represent a good spontaneous model for the human counterpart. Further prospective studies are needed in order to confirm these preliminary results.

The Potential of Immune Checkpoint Blockade in Cervical Cancer: Can Combinatorial Regimens Maximize Response? A Review of the Literature

OPINION STATEMENT

Cervical cancer (CC) is most often caused by the human papillomavirus (HPV). In principle, these ties to the virus should make HPV tumors a relatively easy target for clearance by the immune system. However, these HPV-associated tumors have evolved strategies to escape immune attack. Checkpoint inhibition immunotherapy, which has had remarkable success in cancer treatment, has the potential to overcome the immune escape in CC by harnessing the patient's own immune system and priming it to recognize and kill tumors. Recent work involving PD-1/PD-L1 inhibitors in CC lends credence to this belief, as pembrolizumab has shown evidence of clinical efficacy and consequently been granted accelerated approval by the FDA. That being said, the oncologic outcomes following monotherapy with these biologics have mostly been modest and variable, and this can be attributed to alternative resistance mechanisms to tumor response. The use of therapies that stimulate immune responses via checkpoint-independent activation will therefore augment release of T cell inhibition by checkpoint inhibitors for stronger and more sustained clinical responses. Such a combinatorial approach holds promise for weak- or non-responders to checkpoint therapies as supported by evidence from various, recent pre-clinical, and preliminary clinical studies.

Downregulation of IL-2 and IL-23 in Cervical Biopsies of Cervical Intraepithelial Lesions: A Cross-Sectional Study

INTRODUCTION

Persistent infection with high-risk human papillomavirus (HPV) types is associated with high-grade intraepithelial lesions (HSILs) and invasive cervical cancer. The host immune response plays a key role in whether HPV clears or persists. Most studies on local immune response to HPV collect cervical mucus in order to quantify secreted cytokines; however, cells located inside the tissue can release different cytokines associated with HPV infection.

OBJECTIVE

This study compared the cytokine levels in cervical biopsy specimens of women with abnormal colposcopic findings according to the histopathological results: low-grade intraepithelial lesion (LSIL), HSIL, and no intraepithelial lesion (NSIL).

METHODS

A cross-sectional study enrolling 141 cervical biopsy specimens examined the cytokine profile for interleukin (IL-) 2, IL-4, IL-10, IL-12, IL-17, and IL-23 and interferon-γ, using the Luminex assay/ELISA. Differences in cytokine levels among the cervical lesion groups were assessed using the Kruskal-Wallis test.

RESULTS

The 141 specimens included 90 HSILs, 22 LSILs, and 29 NSILs. IL-2 levels were significantly higher in NSIL samples than in LSIL or in HSIL samples (p = 0.0001) and IL-23 levels were significantly higher in NSIL than in HSIL samples (p = 0.003).

CONCLUSIONS

Our study shows that in samples from the lesion site point, 2 important pro-inflammatory cytokines, IL-2 and IL-23, are downregulated in HPV lesions.

Cervicovaginal microbiome and natural history of HPV in a longitudinal study

BACKGROUND

Human papillomavirus (HPV) infection is one of the most common sexually transmitted infections. However, only a small percentage of high-risk (HR) HPV infections progress to cervical precancer and cancer. In this study, we investigated the role of the cervicovaginal microbiome (CVM) in the natural history of HR-HPV.

METHODS

This study was nested within the placebo arm of the Costa Rica HPV Vaccine Trial that included women aged 18-25 years of age. Cervical samples from two visits of women with an incident HR-HPV infection (n = 273 women) were used to evaluate the prospective role of the CVM on the natural history of HR-HPV. We focus specifically on infection clearance, persistence, and progression to cervical intraepithelial neoplasia grade 2 and 3 (CIN2+). The CVM was characterized by amplification and sequencing the bacterial 16S V4 rRNA gene region and the fungal ITS1 region using an Illumina MiSeq platform. OTU clustering was performed using QIIME2. Functional groups were imputed using PICRUSt and statistical analyses were performed using R.

RESULTS

At Visit 1 (V1) abundance of Lactobacillus iners was associated with clearance of incident HR-HPV infections (Linear Discriminant Analysis (LDA)>4.0), whereas V1 Gardnerella was the dominant biomarker for HR-HPV progression (LDA>4.0). At visit 2 (V2), increased microbial Shannon diversity was significantly associated with progression to CIN2+ (p = 0.027). Multivariate mediation analysis revealed that the positive association of V1 Gardnerella with CIN2+ progression was due to the increased cervicovaginal diversity at V2 (p = 0.040). A full multivariate model of key components of the CVM showed significant protective effects via V1 genus Lactobacillus, OR = 0.41 (0.22-0.79), V1 fungal diversity, OR = 0.90 (0.82-1.00) and V1 functional Cell Motility pathway, OR = 0.75 (0.62-0.92), whereas V2 bacterial diversity, OR = 1.19 (1.03-1.38) was shown to be predictive of progression to CIN2+.

CONCLUSION

This study demonstrates that features of the cervicovaginal microbiome are associated with HR-HPV progression in a prospective longitudinal cohort. The analyses indicated that the association of Gardnerella and progression to CIN2+ may actually be mediated by subsequent elevation of microbial diversity. Identified features of the microbiome associated with HR-HPV progression may be targets for therapeutic manipulation to prevent CIN2+.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00128661.

γδ T cells: pleiotropic immune effectors with therapeutic potential in cancer

The potential of cancer immunotherapy relies on the mobilization of immune cells capable of producing antitumour cytokines and effectively killing tumour cells. These are major attributes of γδ T cells, a lymphoid lineage that is often underestimated despite its major role in tumour immune surveillance, which has been established in a variety of preclinical cancer models. This situation notwithstanding, in particular instances the tumour microenvironment seemingly mobilizes γδ T cells with immunosuppressive or tumour-promoting functions, thus emphasizing the importance of regulating γδ T cell responses in order to realize their translation into effective cancer immunotherapies. In this Review we outline both seminal work and recent advances in our understanding of how γδ T cells participate in tumour immunity and how their functions are regulated in experimental models of cancer. We also discuss the current strategies aimed at maximizing the therapeutic potential of human γδ T cells, on the eve of their exploration in cancer clinical trials that may position them as key players in cancer immunotherapy.

HPV16 E7-Driven Epithelial Hyperplasia Promotes Impaired Antigen Presentation and Regulatory T-Cell Development

Human papillomaviruses infect keratinocytes and can lead to hyperproliferative dysplasia and malignant transformation if not cleared by the immune system. Human papillomavirus has evolved an array of mechanisms to evade and manipulate the immune system to improve replication efficiency and promote persistent infection. We here demonstrate that hyperproliferative skin expressing the high-risk human papillomavirus 16 E7 oncogene as a transgene drives immunomodulation of dendritic cells (DCs), resulting in reduced capacity to take up antigen and prime effector CD4⁺ T cell responses. The phenotype of DCs in the E7-expressing hyperproliferative skin was not reversible by activation through intradermal immunization. Naïve CD4⁺ T cells primed by E7-driven hyperproliferative skin acquired FoxP3 expression and an anergic phenotype. DC and T help modulation was dependent on E7-retinoblastoma protein interaction-driven epithelial hyperproliferation, rather than on expression of E7. Inhibition of binding of E7 to retinoblastoma protein, and of consequent epithelial hyperplasia, was associated with normal skin DC phenotype, and T helper type 1 effector responses to immunization were restored. We conclude that human papillomavirus-induced epithelial hyperplasia modulates epithelial DCs and inhibits T helper type 1 immunity while polarizing T-cell differentiation to a regulatory or anergic phenotype.

The Influence of Cervicovaginal Microbiota on Mucosal Immunity and Prophylaxis in the Battle against HIV

PURPOSE OF REVIEW

Young women in sub-Saharan Africa bear a disproportionate burden of the global HIV epidemic. In this review, we examine how cervicovaginal microbiota modulate structural and immune defenses in the female genital tract and influence HIV susceptibility.

RECENT FINDINGS

Highly diverse, anaerobic cervicovaginal microbiota prevalent in sub-Saharan African women increase HIV acquisition risk by over fourfold. These bacteria weaken the barrier properties of the vaginal mucosa and increase local inflammation and HIV target cell recruitment, creating an environment permissive to HIV. These communities also diminish the prophylactic efficacy of topical tenofovir and therefore may modulate both biological susceptibility to HIV and the effectiveness of pre-exposure prophylaxis (PrEP). Cervicovaginal bacteria influence multiple reproductive health outcomes, including HIV acquisition. High-diversity, low Lactobacillus abundance cervicovaginal communities prevalent in many regions with high HIV incidence are associated with increased HIV susceptibility. A better understanding of the host-microbial interactions mediating this risk is important to reduce HIV infections, particularly among women living in sub-Saharan Africa.

Interleukin-17 expression in the serum and exfoliated cervical cells of patients infected with high-risk oncogenic human papillomavirus

Persistent infection by high-risk oncogenic human papillomavirus (HR-HPV) is the main cause of cervical cancer and its precursor lesions, and both the systemic and local immunological responses play an important role in eliminating or maintenance this infection. Th17 cells, as well as interleukin (IL)-17, are related to tumor growth and persistence of viral infection. Thus, this study aimed to quantify IL-17 in the serum and exfoliated cervical cells of HR-HPV-infected patients and healthy patients as well as identify CD4⁺IL17⁺ cells and IL-17 production in uterine cervix biopsies to better understand the behavior of this cytokine in HPV infections. IL-17 was quantified (pg/mL) in the serum and exfoliated cervical cells of 26 HR-HPV-infected patients, and in 18 healthy patients, using flow cytometry. Fifteen paraffin-embedded biopsy samples from the uterine cervix were subjected to immunohistochemistry to detect CD4⁺IL-17⁺ and IL-17⁺ cells. There was a significant increase in the concentration of IL-17 in HR-HPV-positive patients' serum when compared to that in samples of exfoliated cervical cells (p < 0.05). Likewise, when compared with that in healthy patients, the IL-17 concentration was still higher in HR-HPV-positive patients sera (p < 0.05). We did not find differences in the amount of CD4⁺IL-17⁺ cells and other IL-17-secreting cells between different histopathological lesions. Our results suggest that HR-HPV infection predominantly stimulates systemic IL-17 production along with less localized expression.

Alzheimer's disease might depend on enabling pathogens which do not necessarily cross the blood-brain barrier

The development of Alzheimer's Disease (AD) might reflect, in its acquired aspects, a cooperative pathogenesis whereby infectious enablers which do not necessarily cross the blood-brain barrier augment the invasive properties of a less virulent organism, thus enabling it to infect the brain. An example interaction is described which involves Chlamydia species, Human papillomavirus (HPV), microbiota, and yeast, where yeast is a pathogen of low virulence which crosses the blood-brain barrier. The cooperative pathogenesis begins at the mucosal epithelium. Infection by Chlamydia, HPV, or dysbiosis of commensal bacteria disrupts the integrity of the mucosal epithelium, thereby allowing colonizing yeast to penetrate the epithelial barrier and enter into the bloodstream. Chlamydia and enabling commensals promote insulin resistance, which provides yeast with glucose and also sets the stage for accumulation of amyloid beta protein (ABP). Meanwhile, HPV-induced and hyperglycemia-induced immunological changes enable the spread of newly invasive yeast to the brain, where the release of inflammatory cytokines in response to yeast promotes production of ABP. Chlamydia also cross reacts with Candida species, which may stimulate further brain inflammation in response to Candida and may augment production of ABP thereby The yeast's less virulent origins, coupled with immune modulation by enablers, might explain why AD as a model of infectious encephalitis is always slow and insidious rather than occasionally febrile, accompanied by seizures, or marked by signs of meningeal inflammation.

HPV-negative, but not HPV-positive, oropharyngeal carcinomas induce fibroblasts to support tumour invasion through micro-environmental release of HGF and IL-6

Human papillomavirus (HPV) infection is causally related to a subset of oropharyngeal carcinomas (OPC) and is linked to a more favourable prognosis compared to HPV-negative OPC. The mechanisms underlying this effect on prognosis are not fully understood, but interactions with the tumour microenvironment may be pivotal. Here, we investigated the role of the tumour microenvironment in HPV-positive compared to HPV-negative cancer using 2D and 3D modelling of OPC interactions with stromal fibroblasts. HPV-negative, but not HPV-positive, OPC-derived cell lines induced a rapid fibroblast secretory response that supported 2D cancer cell migration and invasion in vitro. Array profiling of this HPV-negative induced fibroblast secretome identified hepatocyte growth factor (HGF) as the principal secreted factor that promoted cancer cell migration. The interaction between HPV-negative cell lines and fibroblasts in 2D was prevented using c-Met (HGF receptor) inhibitors, which further restricted both HPV-negative and positive cell invasion in 3D co-culture models. Furthermore, we discovered a synergistic relationship between HGF and IL-6 in the support of migration that relates JAK activation to HGF responsiveness in HPV-negative lines. In summary, our data show significant differences in the interactions between HPV-positive and HPV-negative OPC cells and stromal fibroblasts. In addition, we, provide in vitro evidence to support the clinical application of c-MET inhibitors in the control of early HPV-negative OPC.

Th17 response in patients with cervical cancer

Persistent infection by high-risk human papillomavirus (HR-HPV) is the main risk factor for uterine cervical cancer (UCC). However, viral infection alone is not sufficient for the development and progression of premalignant cervical lesions for cancer. In previous years it has been suggested that the adaptive immune response triggered by the differentiation of naïve helper T cells in Th17 cells may serve an important role in disease development. It has been hypothesized that Th17 cells may be involved in the promotion of UCC, as high levels of interleukin 17 (IL17) expression have been detected in the mucosa of the uterine cervix of patients affected by the disease. However, the role of Th17 cells in the tumor development and progression remains unclear. It is believed that the immune response of the Th17 type during persistent infection of the genital tract with HR-HPV triggers chronic inflammation with a long duration with the production of IL17 and other pro-inflammatory cytokines, creating a favorable environment for tumor development. These cytokines are produced by immune system cells in addition to tumor cells and appear to function by modulating the host immune system, resulting in an immunosuppressive response as opposed to inducing an effective protective immune response, thus contributing to the growth and progression of the tumor. In the present review, the latest advances are presented about the function of Th17 cells and the cytokines produced by them in the development and progression of UCC.

Murine HPV16 E7-expressing transgenic skin effectively emulates the cellular and molecular features of human high-grade squamous intraepithelial lesions

Currently available vaccines prevent HPV infection and development of HPV-associated malignancies, but do not cure existing HPV infections and dysplastic lesions. Persistence of infection(s) in immunocompetent patients may reflect induction of local immunosuppressive mechanisms by HPV, providing a target for therapeutic intervention. We have proposed that a mouse, expressing HPV16 E7 oncoprotein under a Keratin 14 promoter (K14E7 mice), and which develops epithelial hyperplasia, may assist with understanding local immune suppression mechanisms that support persistence of HPV oncogene-induced epithelial hyperplasia. K14E7 skin grafts recruit immune cells from immunocompetent hosts, but consistently fail to be rejected. Here, we review the literature on HPV-associated local immunoregulation, and compare the findings with published observations on the K14E7 transgenic murine model, including comparison of the transcriptome of human HPV-infected pre-malignancies with that of murine K14E7 transgenic skin. We argue from the similarity of i) the literature findings and ii) the transcriptome profiles that murine K14E7 transgenic skin recapitulates the cellular and secreted protein profiles of high-grade HPV-associated lesions in human subjects. We propose that the K14E7 mouse may be an appropriate model to further study the immunoregulatory effects of HPV E7 expression, and can facilitate development and testing of therapeutic vaccines.

DNA Vaccine Encoding HPV16 Oncogenes E6 and E7 Induces Potent Cell-mediated and Humoral Immunity Which Protects in Tumor Challenge and Drives E7-expressing Skin Graft Rejection

We have previously shown that a novel DNA vaccine technology of codon optimization and the addition of ubiquitin sequences enhanced immunogenicity of a herpes simplex virus 2 polynucleotide vaccine in mice, and induced cell-mediated immunity when administered in humans at relatively low doses of naked DNA. We here show that a new polynucleotide vaccine using the same technology and encoding a fusion protein of the E6 and E7 oncogenes of high-risk human papillomavirus type 16 (HPV16) is immunogenic in mice. This vaccine induces long-lasting humoral and cell-mediated immunity and protects mice from establishment of HPV16-E7-expressing tumors. In addition, it suppresses growth of readily established tumors and shows enhanced efficacy when combined with immune checkpoint blockade targeted at PD-L1. This vaccine also facilitates rejection of HPV16-E7-expressing skin grafts that demonstrate epidermal hyperplasia with characteristics of cervical and vulvar intraepithelial neoplasia. Clinical studies evaluating the efficacy of this vaccine in patients with HPV16 premalignancies are planned.

HPV16E7-Induced Hyperplasia Promotes CXCL9/10 Expression and Induces CXCR3+ T-Cell Migration to Skin

Chemokines regulate tissue immunity by recruiting specific subsets of immune cells. Mice expressing the E7 protein of human papilloma virus 16 as a transgene from a keratin 14 promoter (K14.E7) show increased epidermal and dermal lymphocytic infiltrates, epidermal hyperplasia, and suppressed local immunity. Here, we show that CXCL9 and CXCL10 are overexpressed in non-hematopoietic cells in skin of K14.E7 mice when compared with non-transgenic animals, and recruit CXCR3⁺ lymphocytes to the hyperplastic skin. Overexpression of CXCL9 and CXCL10 is not observed in E7 transgenic mice with mutated Rb gene whose protein product cannot interact with E7 (K14.E7xRb^ΔL/ΔL) and in consequence lack hyperplastic epithelium. CXCR3⁺ T cells are preferentially recruited by CXCL9 and CXCL10 in supernatants of K14.E7 but not K14.E7xRb^ΔL/ΔL skin cultures in vitro. CXCR3 signalling promotes infiltration of a subset of effector T lymphocytes that enables donor lymphocyte deficient, E7-expressing skin graft rejection. Taken together, this suggests that recruitment of CXCR3⁺ T cells can be an important factor in the rejection of precancerous skin epithelium providing they can overcome local immunosuppressive mechanisms driven by skin-resident lymphocytes.

Human papillomavirus oncoproteins induce a reorganization of epithelial-associated γδ T cells promoting tumor formation

It has been shown that γδ T cells protect against the formation of squamous cell carcinoma (SCC) in several models. However, the role of γδ T cells in human papillomavirus (HPV)-associated uterine cervical SCC, the third-leading cause of death by cancer in women, is unknown. Here, we investigated the impact of γδ T cells in a transgenic mouse model of carcinogenesis induced by HPV16 oncoproteins. Surprisingly, γδ T cells promoted the development of HPV16 oncoprotein-induced lesions. HPV16 oncoproteins induced a decrease in epidermal Skint1 expression and the associated antitumor Vγ5+ γδ T cells, which were replaced by γδ T-cell subsets (mainly Vγ6+ γδlowCCR2+CCR6-) actively producing IL-17A. Consistent with a proangiogenic role, γδ T cells promoted the formation of blood vessels in the dermis underlying the HPV-induced lesions. In human cervical biopsies, IL-17A+ γδ T cells could only be observed at the cancer stage (SCC), where HPV oncoproteins are highly expressed, supporting the clinical relevance of our observations in mice. Overall, our results suggest that HPV16 oncoproteins induce a reorganization of the local epithelial-associated γδ T-cell subpopulations, thereby promoting angiogenesis and cancer development.

Cisplatin inhibits the growth, migration and invasion of cervical cancer cells by down-regulating IL-17E/IL-17RB

Interleukin (IL)-17E mainly produced by immune cells, is a distinct member of the IL-17 cytokine family, which has multifarious immunomodulatory activities. As a potent anticancer drug, cisplatin is commonly used against various types of solid tumors. The present study was performed to investigate whether cisplatin regulates the expression of IL-17E and it receptor IL-17RB, and the role of IL17E in cervical cancer cells in vitro. The expression of IL-17E and IL-17RB in cervical cancer cells was detected by flow cytometry and ELISA. The viability, apoptosis, migration and invasion of cervical cancer cells were analyzed by CCK8, Annexin V-7AAD apoptosis, transwell migration, wound healing, and matrigel invasion assays. Here, we found that cervical cancer cells co-expressed IL-17E and IL-17RB, especially HeLa and SiHa cells. Recombinant human IL-17E protein (rhIL-17E) enhanced the viability, migration and invasion of HeLa and SiHa cells, and blocking IL-17E with anti-human IL-17RE neutralizing antibody promoted the apoptosis of HeLa and SiHa cells. Cisplatin significantly down-regulated the expression of IL-17E and IL-17RB, and further reversed the regulatory effects of rhIL-17E on viability, apoptosis, migration and invasion of HeLa and SiHa cells. The results suggest that cisplatin inhibits the viability, migration, invasion, and promotes the apoptosis of cervical cancer cells possibly by down-regulating IL-17E/17RB signaling. Cisplatin may be the first choice for cervical cancer patients with abnormally high IL-17E expression.

Lactobacillus-Deficient Cervicovaginal Bacterial Communities Are Associated with Increased HIV Acquisition in Young South African Women

Elevated inflammation in the female genital tract is associated with increased HIV risk. Cervicovaginal bacteria modulate genital inflammation; however, their role in HIV susceptibility has not been elucidated. In a prospective cohort of young, healthy South African women, we found that individuals with diverse genital bacterial communities dominated by anaerobes other than Gardnerella were at over 4-fold higher risk of acquiring HIV and had increased numbers of activated mucosal CD4⁺ T cells compared to those with Lactobacillus crispatus-dominant communities. We identified specific bacterial taxa linked with reduced (L. crispatus) or elevated (Prevotella, Sneathia, and other anaerobes) inflammation and HIV infection and found that high-risk bacteria increased numbers of activated genital CD4⁺ T cells in a murine model. Our results suggest that highly prevalent genital bacteria increase HIV risk by inducing mucosal HIV target cells. These findings might be leveraged to reduce HIV acquisition in women living in sub-Saharan Africa.

Seasonal influenza A/H3N2 virus infection and IL-1Β, IL-10, IL-17, and IL-28 polymorphisms in Iranian population

Increased blood cytokines is the main immunopathological process that were attributed to severe clinical outcomes in cases of influenza A/H3N2 virus infection. The study was aimed to investigate the polymorphisms of IL-1β, IL-10, IL-17, and IL-28 genes to find the possibility of their association with the clinical outcome of influenza A/H3N2 virus infection among the infected patients in Iran. This is a Case-Control study in which influenza A/H3N2 virus positive confirmed with real-time PCR were the cases. DNA samples from groups were genotyped for polymorphisms in rs16944 (IL-1β), rs1800872 (IL-10), rs2275913 (IL-17), and rs8099917 (IL-28). Confidence interval (95%CI) and Odds ratio (OR) were calculated. IL-17 rs2275913 (GG and AG) were associated with risk of infection with that were statistically significant (P < 0.05, OR = 2.08-2.94). IL-1β (rs16944) (GG) was associated with reduced risk of infection (P < 0.01, OR = 0.46). Genotype GG and GT of IL-10 (rs1800872) were associated with increased risk of infection with influenza A/H3N2 virus (P < 0.05, OR = 2.04-2.58). In addition, IL-28 (rs8099917) genotypes GG (P < 0.05, OR = 0.49) and TG (P < 0.05, OR = 0.59) were associated with reduced risk of ILI symptom while genotype TT (P < 0.01, OR = 4.31) was associated with increased risk of ILI symptom. The results of this study demonstrated that polymorphisms of genes involved in the inflammatory and anti-inflammatory process affect the outcome of disease caused by influenza A/H3N2 virus. Thorough insight on host immune response at the time of influenza A virus infection is required to ensure adequate patient care in the case of feature outbreaks. J. Med. Virol. 88:2078-2084, 2016. © 2016 Wiley Periodicals, Inc.

The HPV16 E7 Oncoprotein Disrupts Dendritic Cell Function and Induces the Systemic Expansion of CD11b(+)Gr1(+) Cells in a Transgenic Mouse Model

Objective. The aim of this study was to analyze the effects of the HPV16 E7 oncoprotein on dendritic cells (DCs) and CD11b(+)Gr1(+) cells using the K14E7 transgenic mouse model. Materials and Methods. The morphology of DCs was analyzed in male mouse skin on epidermal sheets using immunofluorescence and confocal microscopy. Flow cytometry was used to determine the percentages of DCs and CD11b(+)Gr1(+) cells in different tissues and to evaluate the migration of DCs. Results. In the K14E7 mouse model, the morphology of Langerhans cells and the migratory activity of dendritic cells were abnormal. An increase in CD11b(+)Gr1(+) cells was observed in the blood and skin of K14E7 mice, and molecules related to CD11b(+)Gr1(+) chemoattraction (MCP1 and S100A9) were upregulated. Conclusions. These data suggest that the HPV16 E7 oncoprotein impairs the function and morphology of DCs and induces the systemic accumulation of CD11b(+)Gr1(+) cells.

A Mouse Model of Hyperproliferative Human Epithelium Validated by Keratin Profiling Shows an Aberrant Cytoskeletal Response to Injury

A validated animal model would assist with research on the immunological consequences of the chronic expression of stress keratins KRT6, KRT16, and KRT17, as observed in human pre-malignant hyperproliferative epithelium. Here we examine keratin gene expression profile in skin from mice expressing the E7 oncoprotein of HPV16 (K14E7) demonstrating persistently hyperproliferative epithelium, in nontransgenic mouse skin, and in hyperproliferative actinic keratosis lesions from human skin. We demonstrate that K14E7 mouse skin overexpresses stress keratins in a similar manner to human actinic keratoses, that overexpression is a consequence of epithelial hyperproliferation induced by E7, and that overexpression further increases in response to injury. As stress keratins modify local immunity and epithelial cell function and differentiation, the K14E7 mouse model should permit study of how continued overexpression of stress keratins impacts on epithelial tumor development and on local innate and adaptive immunity.

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Persistence of HPV infection in epithelial premalignancy is not fully understood.

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HPV16 E7 expression in skin induces expression of “stress” keratin.

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“Stress” keratin induction is also observed in human actinic keratosis.

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Induction of “stress” keratins persists after skin grafting of E7-expressing skin.

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Disruption of E7-Retinoblastoma binding abrogates keratin misregulation.

“Stress” keratins modify local immunity and epithelial cell function and differentiation. Thus, identification and validation of a suitable mouse model to study the influence of stress keratin expression normally and during tumor development is important. Mice that transgenically express high-risk HPV16 E7 oncoprotein in the skin (K14E7) presents with epithelial hyperplasia and is used for modeling HPV-associated pre-cancer. We show that “stress” keratins are induced in the K14E7 epithelium, similar to skin from patients with actinic keratosis. Thus the K14E7 mouse should permit study of how continued overexpression of stress keratins impacts on epithelial tumor development and on local immunity.

Both tumour cells and infiltrating T-cells in equine sarcoids express FOXP3 associated with an immune-supressed cytokine microenvironment

Bovine papillomavirus (BPV) infections of equine species have a central role in the aetiology of equine sarcoids; a common benign skin tumour of horses, zebras and donkeys. Within the lesions, all of the early papillomavirus genes are expressed and promote the excessive replication of fibroblasts which characterise these tumours. Equine sarcoids differ from BPV induced fibro-papillomas of cattle (the natural host of BPV), in that they do not produce high amounts of virus particles, do not usually regress spontaneously and do not sero-convert to BPV; features which suggest that affected horses lack an effective anti-viral immune response to BPV. Equine sarcoids contain large numbers of CD4+ CD8+ dual positive T-cells which uniformly express FOXP3, the key transcription factor of regulatory T-cells, and FOXP3 is also expressed within the BPV infected fibroblasts. Compared to healthy skin, sarcoids showed increased mRNA transcription for FOXP3 and the regulatory cytokine TGFβ. Transcription of IL17, which has been shown to have a regulatory function in human papillomavirus-associated tumours, was also elevated in equine sarcoids compared to spleen. In contrast, the levels of mRNA transcripts for effector T cell cytokines IL2, IL4 and interferon-gamma (IFNγ) were not elevated in sarcoids compared to healthy skin or spleen. Similarly neither interferon-alpha (IFNα), interferon-beta (IFNβ) nor IL12 family members were elevated in sarcoids compared to normal skin. We suggest that the regulatory cytokine micro-environment within sarcoids enables the persistence of the lesions by preventing an effective anti-viral immune response.

Epithelium Expressing the E7 Oncoprotein of HPV16 Attracts Immune-Modulatory Dendritic Cells to the Skin and Suppresses Their Antigen-Processing Capacity

Antigen presenting cells (APCs) in skin can promote either antigen-specific effector functions or antigen tolerance, and thus determine clearance or persistence of cutaneous viral infections. Human papillomavirus (HPV) infections can persist in squamous epithelium in immunocompetent individuals, and some persisting HPV infections, particularly with HPV16, promote malignant epithelial transformation. Here, we investigate whether local expression of the HPV16 protein most associated with malignant transformation, HPV16-E7, affects the phenotype and function of APC subsets in the skin. We demonstrate an expanded population of Langerhans cells in HPV16-E7 transgenic skin with distinct cell surface markers which express immune-modulatory enzymes and cytokines not expressed by cells from non transgenic skin. Furthermore, HPV16-E7 transgene expression in keratinocytes attracts new APC subsets to the epidermis. In vivo migration and transport of antigen to the draining lymph node by these APCs is markedly enhanced in HPV16-E7 expressing skin, whereas antigen-processing, as measured by proteolytic cleavage of DQ-OVA and activation of T cells in vivo by APCs, is significantly impaired. These data suggest that local expression of HPV16-E7 in keratinocytes can contribute to persisting infection with this oncogenic virus, by altering the phenotype and function of local APCs.

Symptomatic Improvement in Human Papillomavirus-Induced Epithelial Neoplasia by Specific Targeting of the CXCR4 Chemokine Receptor

Human papillomavirus (HPV) infection is estimated to be the causal agent in 5% of all human cancers and is the leading cause of genital warts, which is the most common sexually transmitted viral disease. Currently, there are no medications to treat HPV infection, and therapeutic strategies primarily target HPV-related cancer rather than viral infection. HPV infection has severe effects on patients who display selective susceptibility to the virus in the context of primary immunodeficiencies, such as the warts, hypogammaglobulinemia, infections, and myelokathexis syndrome, which is caused by dysfunctions of CXCR4, the receptor for the CXCL12 chemokine. In this study we showed in a transgenic mouse model of HPV-induced epidermal neoplasia the beneficial effects of Cxcl12/Cxcr4 pathway blockade with the selective CXCR4 antagonist AMD3100. Daily treatment with AMD3100 for 28 days potently reduced the abnormal ear epidermal thickening in all mice. This effect was associated with reductions in keratinocyte hyperproliferation and immune cell infiltration, both of which are linked to neoplastic progression. Moreover, we observed the abnormal coordinate expression of Cxcl12 and p16INK4a (a surrogate marker of HPV-induced cancers) in dysplastic epidermal keratinocytes, which was inhibited by AMD3100 treatment. These results provide strong evidence for the therapeutic potential of CXCL12/CXCR4 pathway blockade in HPV-induced pathogenesis.

A population-based case-control study of genetic variation in cytokine genes associated with risk of cervical and vulvar cancers

OBJECTIVE

Persistent infection with oncogenic human papillomavirus (HPV) is known to be the necessary cause of cervical cancer and a majority of vulvar cancers. Persistent HPV infections must evade host immune responses, including cytokines released by activated T-helper (Th) cells. In this study, we investigated the risk of cervical and vulvar cancers associated with common genetic variations in 560 tagging single-nucleotide polymorphisms (SNPs) in candidate cytokine genes.

METHODS

The study included 399 invasive squamous cell carcinomas (SCCs) and 502 in situ or invasive adenocarcinomas (AC) of the cervix; 357 in situ or invasive vulvar SCC; and 1109 controls from the Seattle-area case-control studies of HPV-related cancers. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) using a log additive model, with adjustment for multiple testing.

RESULTS

Statistically significant risks were observed for HPV16-containing SCC of the cervix with the variant allele rs879576 in IL17RA and rs2229094 in TNF [OR, 95% CI and multiple-testing corrected p: 1.91 (1.30-2.79), p=0.018 and 0.61 (0.45-0.83), p=0.02, respectively]. We also observed significantly increased risk of HPV-positive vulvar cancers associated with variant alleles in CSF2 (rs25882 and rs27438, 26-28% increased risk) and IL-12B (rs2569254 and rs3181225, 40-41% increased risk) genes.

CONCLUSIONS

We found that variation in several Th-cytokine genes is significantly associated with cervical and vulvar cancer risk. The strong association between these HPV-related cancers and common variation in cytokine genes in the Th1 and Th17 pathways may be important for development of new therapies.

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.

Model systems to study the life cycle of human papillomaviruses and HPV-associated cancers

The prevalent human papillomaviruses (HPVs) infect either cutaneous or mucosal epithelium. Active Infections lead to epithelial hyperprolifeation and are usually cleared in healthy individuals within a year. Persistent infections in the anogenital tracts by certain high-risk genotypes such as HPV-16, HPV-18 and closely related types, can progress to high grade dysplasias and carcinomas in women and men, including cervical, vulva, penile and anal cancers. A significant fraction of the head and neck cancers are also caused by HPV-16. The viral oncogenes responsible for neoplastic conversion are E6 and E7 that disrupt the pathways controlled by the two major tumor suppressor genes, p53 and members of pRB family. Because HPV cannot be propagated in conventional submerged monolayer cell cultures, organotypic epithelial raft cultures that generate a stratified and differentiated epithelium have been used to study the viral life cycle. This article describes several systems to examine aspects of the viral productive phase, along with the advantages and limitations. Animal model systems of HPV carcinogenesis are also briefly described.

IL-10, IL-15, IL-17, and GMCSF levels in cervical cancer tissue of Tanzanian women infected with HPV16/18 vs. non-HPV16/18 genotypes

Background

Despite comparable screening rates for precancerous lesions, higher incidence and mortality related to cervical cancer in minority women persists. Recent evidence suggests that minority women with precancerous cervical lesions harbor a wider range of human papillomavirus (HPV) genotypes, many of these distinct from HPV16/18, those most commonly found in Caucasian women. The goal of the analysis was to determine if inflammatory cytokines and chemokines varied by HPV 16/18 versus other genotypes in cervical cancer tissues from Tanzanian women.

Methods

HPV genotypes and concentrations of chemokines and cytokines were measured from homogenized fresh tumor tissue of thirty-one women with invasive cervical cancer (ICC). Risk factors for cervical cancer including age, parity, hormonal contraceptive use and cigarette smoking were obtained by questionnaire. Generalized linear models were used to evaluate differences between chemokines/cytokine levels in women infected with HPV16/18 and those infected with other HPV genotypes.

Results

After adjusting for age, parity and hormonal contraceptives, IL-17 was found significantly more frequently in invasive cervical cancer samples of women infected with HPV16/18 compared to women infected with other HPV genotypes (p = 0.033). In contrast, higher levels for granular macrophage colony-stimulating factor (p = 0.004), IL-10 (p = 0.037), and IL-15 (p = 0.041) were found in ICC tissues of women infected with genotypes other than HPV16/18 when compared to those of women infected with HPV16/18.

Conclusions

While the small sample size limits inference, our data suggest that infection with different HPV genotypes is associated with distinct pro-inflammatory cytokine expression profiles; whether this explains some of the racial differences observed in cervical cancer is still unclear. Future studies are needed to confirm these findings.

Electronic supplementary material

The online version of this article (doi:10.1186/s13027-015-0005-1) contains supplementary material, which is available to authorized users.

Interleukin-17A Promotes Arginase-1 Production and 2,4-Dinitrochlorobenzene-Induced Acute Hyperinflammation in Human Papillomavirus E7 Oncoprotein-Expressing Skin

Human papillomaviruses (HPVs) have evoked numerous mechanisms to subvert host innate immunity and establish a local immunosuppressive environment to facilitate persistent virus infection. Topical application of 2,4-dinitrochlorobenzene (DNCB) was speculated to overcome this immunosuppressive environment and was employed in the immunotherapy of HPV-associated lesions. We have previously shown that DNCB treatment of skin expressing HPV16.E7 protein, the major oncogenic protein expressed in HPV-associated premalignant cervical epithelium, results in a hyperinflammatory response, with an associated induction of Th2 cytokines and infiltration of myeloid cells producing arginase-1, which also contributes to the hyperinflammation. However, the molecular mechanisms underlying arginase-1 induction and arginase-mediated hyperinflammation in K14.E7 skin have not been elucidated. Here, we show that HPV16.E7 protein expression as a transgene in skin is associated with enhanced IL-17A production by macrophages exposed to DNCB. Interestingly, induction of arginase-1 by DNCB is not seen in K14.E7 animals unable to express IL-17A. Further, blockade of either IL-17A or arginase activity alleviates DNCB-induced hyperinflammation through reduced recruitment of neutrophils, as a consequence of decreased CXCL1 and CXCL5 chemokine production. Thus, our findings suggest that increased IL-17A expression by macrophages in E7-expressing skin exposed to DNCB promotes arginase-1 induction and contributes directly to the observed hyperinflammation.