Monocytes attracted by tumor-induced chronic inflammation differentiate to APCs, the type of which depends on cues in the local tumor milieu. In this work, we studied the influence of human cervical cancer cells on monocyte differentiation and showed that the majority of cancer cells either hampered monocyte to dendritic cell differentiation or skewed their differentiation toward M2-like macrophages. Blocking studies revealed that M2 differentiation was caused by tumor-produced PGE2 and IL-6. TGF-β, IL-10, VEGF, and macrophage colony-stimulating factor did not play a role. Notably, these CD14+CD163+ M2 macrophages were also detected in situ. Activation of cancer cell-induced M2-like macrophages by several TLR-agonists revealed that compared with dendritic cells, these M2 macrophages displayed a tolerogenic phenotype reflected by a lower expression of costimulatory molecules, an altered balance in IL-12p70 and IL-10 production, and a poor capacity to stimulate T cell proliferation and IFN-γ production. Notably, upon cognate interaction with Th1 cells, these tumor-induced M2 macrophages could be switched to activated M1-like macrophages that expressed high levels of costimulatory molecules, produced high amounts of IL-12 and low amounts of IL-10, and acquired the lymphoid homing marker CCR7. The effects of the interaction between M2 macrophages and Th1 cells could partially be mimicked by activation of these APCs via CD40 in the presence of IFN-γ. Our data on the presence, induction, and plasticity of tumor-induced tolerogenic APCs in cervical cancer suggest that tumor-infiltrated Th1 cells can stimulate a tumor-rejecting environment by switching M2 macrophages to classical proinflammatory M1 macrophages.

One half of a group of 20 patients with human papillomavirus type 16 (HPV16)-induced vulvar intraepithelial neoplasia grade 3 displayed a complete regression (CR) after therapeutic vaccination with HPV16 E6/E7 synthetic long peptides. Patients with relatively larger lesions generally did not display a CR. To investigate immune correlates of treatment failure, patients were grouped according to median lesion size at study entry, and HPV16-specific immunity was analyzed at different time points by complementary immunological assays. The group of patients with smaller lesions displayed stronger and broader vaccine-prompted HPV16-specific proliferative responses with higher IFNγ (P = 0.0003) and IL-5 (P < 0.0001) levels than patients with large lesions. Characteristically, this response was accompanied by a distinct peak in cytokine levels after the first vaccination. In contrast, the patient group with larger lesions mounted higher frequencies of HPV16-specific CD4 + CD25 + Foxp3 + T cells (P = 0.005) and displayed a lower HPV16-specific IFNγ/IL-10 ratio after vaccination (P < 0.01). No disparity in T memory immunity to control antigens was found, indicating that the differences in HPV-specific immunity did not reflect general immune failure. We observed a strong correlation between a defined set of vaccine-prompted specific immune responses and the clinical efficacy of therapeutic vaccination. Notably, a high ratio of HPV16-specific vaccine-prompted effector T cells to HPV16-specific CD4 + CD25 + Foxp3 + T cells was predictive of clinical success. Foxp3 + T cells have been associated previously with impaired immunity in malignancies. Here we demonstrate that the vaccine-prompted level of this population is associated with early treatment failure.human papilloma virus | immunomonitoring | therapeutic vaccine | regulatory T cells

No abstract

One of the hallmarks of cancer is the influx of myeloid cells. In our study, we investigated the constitution of tumorinfiltrating myeloid cells and their relationship to other tumor-infiltrating immune cells, tumor characteristics and the diseasespecific survival of patients with cervical cancer (CxCa). Triple-color immunofluorescence confocal microscopy was used to locate, identify and quantify macrophages (CD14), their maturation status (CD33) and their polarization (CD163) in a cohort of 86 patients with cervical carcinoma. Quantification of the numbers of myeloid cells revealed that a strong intraepithelial infiltration of CD141 cells, and more specifically the population of CD141CD332CD1632 matured M1 macrophages, is associated with a large influx of intraepithelial T lymphocytes (p 5 0.008), improved disease-specific survival (p 5 0.007) and forms an independent prognostic factor for survival (p 5 0.033). The intraepithelial CD81 T-cell and regulatory T-cell (Treg) ratio also forms an independent prognostic factor (p 5 0.010) and combination of these two factors reveals a further increased benefit in survival for patients whose tumor displays a dense infiltration with intraepithelial matured M1 macrophages and a high CD8 T-cell/Treg ratio, indicating that both populations of immune cells simultaneously improve survival. Subsequently, we made a heatmap including all known immune parameters for these patients, whereby we were able to identify different immune signatures in CxCa. These results indicate that reinforcement and activation of the intratumoral M1 macrophages may form an attractive immunotherapeutic option in CxCa. Cervical cancer (CxCa) is caused by high-risk human papillomavirus (HPV).1 Studies on HPV-specific T-cell responses in patients with premalignant disease suggest that spontaneous regression occurs when circulating HPV early antigen-specific CD41 and CD81 T-cells are present and when the lesions are infiltrated with effector T-cells that outnumber regulatory Tcells (Tregs). Moreover, the presence of circulating HPVspecific CD41 T-cells is associated with T-cell infiltration in the lesion and favorable clinical outcome in high-grade squamous intraepithelial lesion after treatment.2,3 The development of CxCa is associated with a weak systemic and local immune response to HPV, reflected by low numbers of tumorinfiltrating T-cells comprising CD81 cytotoxic T-cells, CD41 T-helper cells and Tregs. [4][5][6] The T-cells present often lack cytotoxicity 7 and/or express coinhibitory molecules such as programmed cell death protein 1, CD94 and NKG2a. 8,9 Tumors also downregulate human leukocyte antigen (HLA) class I and MHC class I chain-related molecule A (MICA) and upregulate HLA-E and PD-L1 to further restrain the CD81 T-cell response. 2,[8][9][10] The presence of circulating HPV-specific T-cells associates with better survival and high numbers of T-cells correlate with the absence of metastases or a relapse. 2,6,11,12 Importantly, the ratio between tumor-infiltrating CD81 and Foxp31 T-cells wa...