The importance of correctly timing cancer immunotherapy

Transplantation and autoimmunit

Interferon-gamma and IL-5 associated cell-mediated immune responses to HPV16 E2 and E6 distinguish between persistent oral HPV16 infections and noninfected mucosa

Objectives: Natural history of human papillomavirus (HPV) infection in the head and neck region is poorly understood, and their impact on collective HPV-specific immunity is not known.Materials and methods: In this study, we have performed a systematic analysis of HPV16-specific cell-mediated immunity (CMI) in 21 women with known oral and genital HPV DNA status and HPV serology (Ab) based on 6-year follow-up data. These women being a subgroup from the Finnish Family HPV Study were recalled for blood sampling to be tested for their CMI-responses to HPV16 E2, E6, and E7 peptides.Results: The results showed that HPV16 E2-specific lymphocyte proliferation was more prevalent in women who tested HPV16 DNA negative in oral mucosa and were either HPV16 seropositive or negative than in HPV16 DNA+/Ab+ women (p = 0.046 and p = 0.035). In addition, the HPV16 DNA-/Ab- women most often displayed E6-specific proliferation (p = 0.020). Proportional cytokine profiles indicated that oral HPV16-negative women were characterized by prominent IFN-gamma and IL-5 secretion not found in women with persisting oral HPV16 (p = 0.014 and p = 0.040, respectively).Conclusions: Our results indicate that the naturally arising immune response induced by oral HPV infections displays a mixed Th1/Th2/Th17 cytokine profile while women with persisting oral HPV16 might have an impaired HPV16-specific CMI, shifted partly toward a Th2 profile, similarly as seen earlier among patients with high-grade genital HPV lesions. Thus, the lack of HPV 16 E2 and E6 specific T memory cells and Th2 cytokines might also predispose women for persistent oral HPV16 infection which might be related to the risk of cancer.Experimental cancer immunology and therap

Predictive biomarkers for outcomes of immune checkpoint inhibitors (ICIs) in melanoma: a systematic review

Simple Summary Immune checkpoint inhibitors (ICIs) have revolutionized treatment of advanced melanoma and survival of melanoma patients has radically improved since. However, as durable responses after ICIs are only observed in 30-50% of melanoma patients, there is an unmet need to identify predictive biomarkers for response. This systematic review demonstrates the substantial number of publications that have studied a wide variety of possible biomarkers. Covering 177 publications that investigated 128 unique biomarkers, we provide an overview of all studied biomarkers in correlation with response or survival. We highlight blood, tumor and fecal biomarkers that were associated with response to ICIs in multiple studies. Of these, only T-cell inflamed gene expression profiling was predictive for response in a large clinical trial and validated in other studies, thus representing a promising biomarker for clinical practice. Large validation studies are warranted to confirm the predictive utility of other biomarkers, thereby further personalizing immunotherapy treatment. Immune checkpoint inhibitors (ICIs) have strongly improved the survival of melanoma patients. However, as durable response to ICIs are only seen in a minority, there is an unmet need to identify biomarkers that predict response. Therefore, we provide a systematic review that evaluates all biomarkers studied in association with outcomes of melanoma patients receiving ICIs. We searched Pubmed, COCHRANE Library, Embase, Emcare, and Web of Science for relevant articles that were published before June 2020 and studied blood, tumor, or fecal biomarkers that predicted response or survival in melanoma patients treated with ICIs. Of the 2536 identified reports, 177 were included in our review. Risk of bias was high in 40%, moderate in 50% and low in 10% of all studies. Biomarkers that correlated with response were myeloid-derived suppressor cells (MDSCs), circulating tumor cells (CTCs), CD8+ memory T-cells, T-cell receptor (TCR) diversity, tumor-infiltrating lymphocytes (TILs), gene expression profiling (GEP), and a favorable gut microbiome. This review shows that biomarkers for ICIs in melanoma patients are widely studied, but heterogeneity between studies is high, average sample sizes are low, and validation is often lacking. Future studies are needed to further investigate the predictive utility of some promising candidate biomarkers.Surgical oncolog

Photochemical internalization enhanced vaccination is safe, and gives promising cellular immune responses to an HPV peptide-based vaccine in a phase I clinical study in healthy volunteers

Background and Aims: Photochemical internalization (PCI) is a technology for inducing release of endocytosed antigens into the cell cytosol via a light-induced process. Preclinical experiments have shown that PCI improves MHC class I antigen presentation, resulting in strongly enhanced CD8+ T-cell responses to polypeptide antigens. In PCI vaccination a mixture of the photosensitizing compound fimaporfin, vaccine antigens, and an adjuvant is administered intradermally followed by illumination of the vaccination site. This work describes an open label, phase I study in healthy volunteers, to assess the safety, tolerability, and immune response to PCI vaccination in combination with the adjuvant poly-ICLC (Hiltonol) (ClinicalTrials.gov Identifier: NCT02947854).Methods: The primary objective of the study was to assess the safety and local tolerance of PCI mediated vaccination, and to identify a safe fimaporfin dose for later clinical studies. A secondary objective was to analyze the immunological responses to the vaccination. Each subject received 3 doses of HPV16 E7 peptide antigens and two doses of Keyhole Limpet Hemocyanin (KLH) protein. A control group received Hiltonol and vaccine antigens only, whereas the PCI groups in addition received fimaporfin + light. Local and systemic adverse effects were assessed by standard criteria, and cellular and humoral immune responses were analyzed by ELISpot, flow cytometry, and ELISA assays.Results: 96 healthy volunteers were vaccinated with fimaporfin doses of 0.75-50 mu g. Doses below 17.5 mu g were safe and tolerable, higher doses exhibited local tolerability issues in some study subjects, mainly erythema, and pain during illumination. There were few, and only mild and expected systemic adverse events. The employment of PCI increased the number of subjects exhibiting a T-cell response to the HPV peptide vaccine about 10-fold over what was achieved with the antigen/Hiltonol combination without PCI. Moreover, the use of PCI seemed to result in a more consistent and multifunctional CD8+ T-cell response. An enhancement of the humoral immune response to KLH vaccination was also observed.Conclusions: Using PCI in combination with Hiltonol for intradermal vaccination is safe at fimaporfin doses below 17.5 mu g, and gives encouraging immune responses to peptide and protein based vaccination.Experimental cancer immunology and therap

Development of an RNA-based kit for easy generation of TCR-engineered lymphocytes to control T-cell assay performance

Experimental cancer immunology and therap

T and NK cells in IL2RG-deficient patient 50 years after hematopoietic stem cell transplantation

The first successful European hematopoietic stem cell transplantation (HSCT) was performed in 1968 as treatment in a newborn with IL2RG deficiency using an HLA-identical sibling donor. Because of declining naive T and natural killer (NK) cells, and persistent human papilloma virus (HPV)-induced warts, the patient received a peripheral stem cell boost at the age of 37 years. NK and T cells were assessed before and up to 14 years after the boost by flow cytometry. The boost induced renewed reconstitution of functional NK cells that were 14 years later enriched for CD56(dim)CD27(+) NK cells. T-cell phenotype and T-cell receptor (TCR) repertoire were simultaneously analyzed by including TCR V beta antibodies in the cytometry panel. Naive T-cell numbers with a diverse TCR V beta repertoire were increased by the boost. Before and after the boost, clonal expansions with a homogeneous TIGIT and PD-1 phenotype were identified in the CD27(-) and/or CD28(-) memory population in the patient, but not in the donor. TRB sequencing was applied on sorted T-cell subsets from blood and on T cells from skin biopsies. Abundant circulating CD8 memory clonotypes with a chronic virus-associated CD57(+)KLRG1(+)CX3CR1(+) phenotype were also present in warts, but not in healthy skin of the patient, suggesting a link with HPV. In conclusion, we demonstrate in this IL2RG-deficient patient functional NK cells, a diverse and lasting naive T-cell compartment, supported by a stem cell boost, and an oligoclonal memory compartment half a century after HSCT.Transplantation and immunomodulatio

Impact of (chemo)radiotherapy on immune cell composition and function in cervical cancer patients

Experimental cancer immunology and therap

CD161 expression and regulation defines rapidly responding effector CD4+T cells associated with improved survival in HPV16-associated tumors

Background Expression of killer cell lectin-like receptor B1 (KLRB1), the gene encoding the cell surface molecule CD161, is associated with favorable prognosis in many cancers. CD161 is expressed by several lymphocyte populations, but its role and regulation on tumor-specific CD4+ T cells is unknown. Methods We examined the clinical impact of CD4+CD161+ T cells in human papillomavirus (HPV)16+ oropharyngeal squamous cell carcinoma (OPSCC), analyzed their contribution in a cohort of therapeutically vaccinated patients and used HPV16-specific CD4+CD161+ tumor-infiltrating lymphocytes and T cell clones for in-depth mechanistic studies. Results Central and effector memory CD4+ T cells express CD161, but only CD4+CD161+ effector memory T cells (Tem) are associated with improved survival in OPSCC. Therapeutic vaccination activates and expands type 1 cytokine-producing CD4+CD161+ effector T cells. The expression of CD161 is dynamic and follows a pattern opposite of the checkpoint molecules PD1 and CD39. CD161 did not function as an immune checkpoint molecule as demonstrated using multiple experimental approaches using antibodies to block CD161 and gene editing to knockout CD161 expression. Single-cell transcriptomics revealed KLRB1 expression in many T cell clusters suggesting differences in their activation. Indeed, CD4+CD161+ effector cells specifically expressed the transcriptional transactivator SOX4, known to enhance T cell receptor (TCR) signaling via CD3 epsilon. Consistent with this observation, CD4+CD161+ cells respond more vigorously to limiting amounts of cognate antigen in presence of interleukin (IL)-12 and IL-18 compared to their CD161- counterparts. The expression of CD161/KLRB1 and SOX4 was downregulated upon TCR stimulation and this effect was boosted by transforming growth factor (TGF)beta 1. Conclusion High levels of CD4+CD161+ Tem are associated with improved survival and our data show that CD161 is dynamically regulated by cell intrinsic and extrinsic factors. CD161 expressing CD4+ T cells rapidly respond to suboptimal antigen stimulation suggesting that CD161, similar to SOX4, is involved in the amplification of TCR signals in CD4+ T cells.Tumorimmunolog

PROTECT: prospective phase-II-trial evaluating adaptive proton therapy for cervical cancer to reduce the impact on morbidity and the immune system

Biological, physical and clinical aspects of cancer treatment with ionising radiatio