Highly immunosuppressive HLADRhi regulatory T cells are associated with unfavorable outcomes in cervical squamous cell carcinoma

Defining Human Regulatory T Cells beyond FOXP3: The Need to Combine Phenotype with Function

Regulatory T cells (Tregs) are essential to maintain immune homeostasis by promoting self-tolerance. Reduced Treg numbers or functionality can lead to a loss of tolerance, increasing the risk of developing autoimmune diseases. An overwhelming variety of human Tregs has been described, based on either specific phenotype, tissue compartment, or pathological condition, yet the bulk of the literature only addresses CD25-positive and CD127-negative cells, coined by naturally occurring Tregs (nTregs), most of which express the transcription factor Forkhead box protein 3 (FOXP3). While the discovery of FOXP3 was seminal to understanding the origin and biology of nTregs, there is evidence in humans that not all T cells expressing FOXP3 are regulatory, and that not all Tregs express FOXP3. Namely, the activation of human T cells induces the transient expression of FOXP3, irrespective of whether they are regulatory or inflammatory effectors, while some induced T cells that may be broadly defined as Tregs (e.g., Tr1 cells) typically lack demethylation and do not express FOXP3. Furthermore, it is unknown whether and how many nTregs exist without FOXP3 expression. Several other candidate regulatory molecules, such as GITR, Lag-3, GARP, GPA33, Helios, and Neuropilin, have been identified but subsequently discarded as Treg-specific markers. Multiparametric analyses have uncovered a plethora of Treg phenotypes, and neither single markers nor combinations thereof can define all and only Tregs. To date, only the functional capacity to inhibit immune responses defines a Treg and distinguishes Tregs from inflammatory T cells (Teffs) in humans. This review revisits current knowledge of the Treg universe with respect to their heterogeneity in phenotype and function. We propose that it is unavoidable to characterize human Tregs by their phenotype in combination with their function, since phenotype alone does not unambiguously define Tregs. There is an unmet need to align the expression of specific markers or combinations thereof with a particular suppressive function to coin functional Treg entities and categorize Treg diversity.

A Phase II Open-Label Randomized Clinical Trial of Preoperative Durvalumab or Durvalumab plus Tremelimumab in Resectable Head and Neck Squamous Cell Carcinoma

PURPOSE

Clinical implications of neoadjuvant immunotherapy in patients with locally advanced but resectable head and neck squamous cell carcinoma (HNSCC) remain largely unexplored.

PATIENTS AND METHODS

Patients with resectable HNSCC were randomized to receive a single dose of preoperative durvalumab (D) with or without tremelimumab (T) before resection, followed by postoperative (chemo)radiotherapy based on multidisciplinary discretion and 1-year D treatment. Artificial intelligence (AI)-powered spatial distribution analysis of tumor-infiltrating lymphocytes and high-dimensional profiling of circulating immune cells tracked dynamic intratumoral and systemic immune responses.

RESULTS

Of the 48 patients enrolled (D, 24 patients; D+T, 24 patients), 45 underwent surgical resection per protocol (D, 21 patients; D+T, 24 patients). D±T had a favorable safety profile and did not delay surgery. Distant recurrence-free survival (DRFS) was significantly better in patients treated with D+T than in those treated with D monotherapy. AI-powered whole-slide image analysis demonstrated that D+T significantly reshaped the tumor microenvironment toward immune-inflamed phenotypes, in contrast with the D monotherapy or cytotoxic chemotherapy. High-dimensional profiling of circulating immune cells revealed a significant expansion of T-cell subsets characterized by proliferation and activation in response to D+T therapy, which was rare following D monotherapy. Importantly, expansion of specific clusters in CD8+ T cells and non-regulatory CD4+ T cells with activation and exhaustion programs was associated with prolonged DRFS in patients treated with D+T.

CONCLUSIONS

Preoperative D±T is feasible and may benefit patients with resectable HNSCC. Distinct changes in the tumor microenvironment and circulating immune cells were induced by each treatment regimen, warranting further investigation.

A disrupted FOXP3 transcriptional signature underpins systemic regulatory T cell insufficiency in early pregnancy failure

Regulatory T (Treg) cell defects are implicated in disorders of embryo implantation and placental development, but the origins of Treg cell dysfunction are unknown. Here, we comprehensively analyzed the phenotypes and transcriptional profile of peripheral blood Treg cells in individuals with early pregnancy failure (EPF). Compared to fertile subjects, EPF subjects had 32% fewer total Treg cells and 54% fewer CD45RA+CCR7+ naive Treg cells among CD4+ T cells, an altered Treg cell phenotype with reduced transcription factor FOXP3 and suppressive marker CTLA4 expression, and lower Treg:Th1 and Treg:Th17 ratios. RNA sequencing demonstrated an aberrant gene expression profile, with upregulation of pro-inflammatory genes including CSF2, IL4, IL17A, IL21, and IFNG in EPF Treg cells. In silico analysis revealed 25% of the Treg cell dysregulated genes are targets of FOXP3. We conclude that EPF is associated with systemic Treg cell defects arising due to disrupted FOXP3 transcriptional control and loss of lineage fidelity.

Beyond FOXP3: a 20-year journey unravelling human regulatory T-cell heterogeneity

The initial idea of a distinct group of T-cells responsible for suppressing immune responses was first postulated half a century ago. However, it is only in the last three decades that we have identified what we now term regulatory T-cells (Tregs), and subsequently elucidated and crystallized our understanding of them. Human Tregs have emerged as essential to immune tolerance and the prevention of autoimmune diseases and are typically contemporaneously characterized by their CD3+CD4+CD25high CD127lowFOXP3+ phenotype. It is important to note that FOXP3+ Tregs exhibit substantial diversity in their origin, phenotypic characteristics, and function. Identifying reliable markers is crucial to the accurate identification, quantification, and assessment of Tregs in health and disease, as well as the enrichment and expansion of viable cells for adoptive cell therapy. In our comprehensive review, we address the contributions of various markers identified in the last two decades since the master transcriptional factor FOXP3 was identified in establishing and enriching purity, lineage stability, tissue homing and suppressive proficiency in CD4+ Tregs. Additionally, our review delves into recent breakthroughs in innovative Treg-based therapies, underscoring the significance of distinct markers in their therapeutic utilization. Understanding Treg subsets holds the key to effectively harnessing human Tregs for immunotherapeutic approaches.

Spectroscopic characterization of eupalitin-3-O-β-D-galactopyranoside from Boerhavia procumbens: In vivo hepato-protective potential in rat model

The liver is one of the most important organs responsible for detoxifying biomolecules and xenobiotics. Herein, we report the isolation, characterization, and hepatoprotective effect of the Boerhavia procumbens-derived eupalitin-3-O-β-D-galactopyranoside (EGP) compound. The structure of the EGP compound was deduced by using NMR spectroscopic techniques and mass spectrometry. The EGP hepatoprotective activities were evaluated with HepG2 cell viability and LDH assays in vitro, and CCl4-induced toxicity was investigated in vivo in the rat model. Compared to the CCl4-treated group, cells exposed to the EGP compound at 200 µg/ml showed increased cell viability (60.52 ± 1.22 %) and decreased LDH levels (23.81 ± 1.89 U/ml). The serum levels of SGPT, SGOT, ALP, and total bilirubin in the CCl4-treated group were substantially higher than those in the control group (64 ± 1.89 U/ml, 86 ± 1.47 U/ml, 252.6 ± 2.96 U/ml, and 5.45 ± 0.32 mg/dl, respectively). When compared to animals treated with CCl4 alone, the EGP compound's in vivo hepatoprotective effect at 60 mg/kg with CCl4 significantly (p < 0.01) decreased the levels of SGPT and SGOT (26 ± 1.34 U/ml and 42.92 ± 1.6 U/ml) respectively. Furthermore, our histological study showed a significant response in restoring and maintaining the normal morphological appearance of the liver. Thus, our results show that the EGP compound is a promising and novel lead molecule for better hepatotoxicity control and therapy.

Transcriptome profiling of regulatory T cells from children with transient hypogammaglobulinemia of infancy

Transient hypogammaglobulinemia of infancy (THI) is one of the most common forms of hypogammaglobulinemia in the early childhood. THI is usually associated with chronic, recurrent bacterial and viral infections, life-threatening in some cases, yet its pathogenesis is still largely unknown. As our previous findings indicated the possible role of Treg cells in the pathomechanism of THI, the aim of the current study was to investigate gene expression profile of Treg cells isolated from THI patients. The transcriptome-wide gene profiling was performed using microarray technology on THI patients in two time-points: during (THI-1), and in resolution phase (THI-2) of hypogammaglobulinemia. As a result, a total of 1086 genes were differentially expressed in THI-1 patients, when compared to THI-2 as well as control group. Among them, 931 were up- and 155 downregulated, and part of them encodes genes important for Treg lymphocyte biology and function, i.e. transcription factors/cofactors that regulate FOXP3 expression. Thus, we postulate that Treg cells isolated from THI patients during hypogammaglobulinemia display enhanced suppressor transcriptome signature. Treg expression profile of THI children after normalization of Ig levels largely resembles the results obtained in healthy control group, suggesting THI Treg transcriptome seems to return to that observed in healthy children. Taken together, we suggest that THI pathomechanism is associated not only with transiently elevated Treg cell numbers, but also with their enhanced regulatory/inhibitory functions. These findings expand our knowledge of human Treg cells and may be useful for the future diagnosis or management of THI.

TMPRSS11D/ALR-mediated ER stress regulates the function of myeloid-derived suppressor cells in the cervical cancer microenvironment

Myeloid-derived suppressor cells (MDSCs) contribute to tumor immune evasion, and have been identified as immunosuppressive cells in cervical cancer. The effect of TMPRSS11D (transmembrane serine protease 11D) in some cancers has been reported, but its role in immune escape of cervical cancer is still unclear. This study aims to elucidate the regulatory mechanism of TMPRSS11D on the immunosuppressive function of MDSCs in cervical cancer. Our data showed that the proportion of polymorphonucleoid MDSCs (PMN-MDSCs), the contents of immunosuppressive factors (including INOS, IDO, and ARG-1) secreted by MDSCs, and TMPRSS11D mRNA level in peripheral blood mononuclear cells (PBMCs) of malignant cervical cancer patients was significantly higher than that of benign tumor patients. Next, CD3+ T cells from PBMCs of cervical cancer patients were stimulated with anti-CD3 and anti-CD28, and then co-cultured with PMN-MDSCs from the same donors at a ratio of 1:2 for 3 days. PMN-MDSCs from malignant tumors produced more ROS, while TMPRSS11D knockdown blocked ROS production. PMN-MDSCs inhibited T cell proliferation and IFN-γ production, while silencing TMPRSS11D in PMN-MDSCs hindered the immunosuppressive effect of PMN-MDSCs. Mechanistically, TMPRSS11D bound to ALR (Augmenter of liver regeneration) and negatively regulated ALR expression, inducing ER stress in PMN-MDSCs, thereby enhancing the immunosuppressive effect of PMN-MDSCs on T cells. Additionally, mouse xenograft tumor assay was conducted to assess the role of TMPRSS11D in tumor growth and MDSC accumulation in vivo. Silencing TMPRSS11D impeded the growth of cervical cancer xenografts and reduced the accumulation of MDSCs in tumor tissues. In conclusion, TMPRSS11D induced ER stress in MDSCs through negative regulation of ALR, thus enhancing the immunosuppressive effect of MDSCs on T cells, so as to promote the growth of cervical cancer tumors.

A key driver to promote HCC: Cellular crosstalk in tumor microenvironment

Liver cancer is the third greatest cause of cancer-related mortality, which of the major pathological type is hepatocellular carcinoma (HCC) accounting for more than 90%. HCC is characterized by high mortality and is predisposed to metastasis and relapse, leading to a low five-year survival rate and poor clinical prognosis. Numerous crosstalk among tumor parenchymal cells, anti-tumor cells, stroma cells, and immunosuppressive cells contributes to the immunosuppressive tumor microenvironment (TME), in which the function and frequency of anti-tumor cells are reduced with that of associated pro-tumor cells increasing, accordingly resulting in tumor malignant progression. Indeed, sorting out and understanding the signaling pathways and molecular mechanisms of cellular crosstalk in TME is crucial to discover more key targets and specific biomarkers, so that develop more efficient methods for early diagnosis and individualized treatment of liver cancer. This piece of writing offers insight into the recent advances in HCC-TME and reviews various mechanisms that promote HCC malignant progression from the perspective of mutual crosstalk among different types of cells in TME, aiming to assist in identifying the possible research directions and methods in the future for discovering new targets that could prevent HCC malignant progression.

Hypoxia-driven immunosuppression by Treg and type-2 conventional dendritic cells in HCC

BACKGROUND AND AIMS

Hypoxia is one of the central players in shaping the immune context of the tumor microenvironment (TME). However, the complex interplay between immune cell infiltrates within the hypoxic TME of HCC remains to be elucidated.

APPROACH AND RESULTS

We analyzed the immune landscapes of hypoxia-low and hypoxia-high tumor regions using cytometry by time of light, immunohistochemistry, and transcriptomic analyses. The mechanisms of immunosuppression in immune subsets of interest were further explored using in vitro hypoxia assays. Regulatory T cells (Tregs) and a number of immunosuppressive myeloid subsets, including M2 macrophages and human leukocyte antigen-DR isotype (HLA-DR^lo ) type 2 conventional dendritic cell (cDC2), were found to be significantly enriched in hypoxia-high tumor regions. On the other hand, the abundance of active granzyme B^hi PD-1^lo CD8⁺ T cells in hypoxia-low tumor regions implied a relatively active immune landscape compared with hypoxia-high regions. The up-regulation of cancer-associated genes in the tumor tissues and immunosuppressive genes in the tumor-infiltrating leukocytes supported a highly pro-tumorigenic network in hypoxic HCC. Chemokine genes such as CCL20 (C-C motif chemokine ligand 20) and CXCL5 (C-X-C motif chemokine ligand 5) were associated with recruitment of both Tregs and HLA-DR^lo cDC2 to hypoxia-high microenvironments. The interaction between Tregs and cDC2 under a hypoxic TME resulted in a loss of antigen-presenting HLA-DR on cDC2.

CONCLUSIONS

We uncovered the unique immunosuppressive landscapes and identified key immune subsets enriched in hypoxic HCC. In particular, we identified a potential Treg-mediated immunosuppression through interaction with a cDC2 subset in HCC that could be exploited for immunotherapies.

Ubiquitin ligase RNF125 targets PD-L1 for ubiquitination and degradation

As a critical immune checkpoint molecule, PD-L1 is expressed at significantly higher levels in multiple neoplastic tissues compared to normal ones. PD-L1/PD-1 axis is a critical target for tumor immunotherapy, blocking the PD-L1/PD-1 axis is recognized and has achieved unprecedented success in clinical applications. However, the clinical efficacy of therapies targeting the PD-1/PD-L1 pathway remains limited, emphasizing the need for the mechanistic elucidation of PD-1/PD-L1 expression. In this study, we found that RNF125 interacted with PD-L1 and regulated PD-L1 protein expression. Mechanistically, RNF125 promoted K48-linked polyubiquitination of PD-L1 and mediated its degradation. Notably, MC-38 and H22 cell lines with RNF125 knockout, transplanted in C57BL/6 mice, exhibited a higher PD-L1 level and faster tumor growth than their parental cell lines. In contrast, overexpression of RNF125 in MC-38 and H22 cells had the opposite effect, resulting in lower PD-L1 levels and delayed tumor growth compared with parental cell lines. In addition, immunohistochemical analysis of MC-38 tumors with RNF125 overexpression showed significantly increased infiltration of CD4+, CD8+ T cells and macrophages. Consistent with these findings, analyses using The Cancer Genome Atlas (TCGA) public database revealed a positive correlation of RNF125 expression with CD4+, CD8+ T cell and macrophage tumor infiltration. Moreover, RNF125 expression was significantly downregulated in several human cancer tissues, and was negatively correlated with the clinical stage of these tumors, and patients with higher RNF125 expression had better clinical outcomes. Our findings identify a novel mechanism for regulating PD-L1 expression and may provide a new strategy to increase the efficacy of immunotherapy.

Accumulation of dysfunctional tumor-infiltrating PD-1+ DCs links PD-1/PD-L1 blockade immunotherapeutic response in cervical cancer

Various predictive biomarkers are needed to select candidates for optimal and individualized treatments. Tumor‐infiltrating immune cells have gained increasing interest in cancer research for the prediction of therapeutic response and survival. However, the role of dendritic cells (DCs) in PD-1 blockade immunotherapy remains unclear. In this study, we identified a population of PD-1+ DCs in the tumor microenvironment (TME) of cervical cancer (CC). The accumulation of PD-1+ DCs in cervical tumors was correlated with advanced stages, elevated preoperative squamous cell carcinoma antigen levels and lymph-vascular space invasion. PD-1 expression was induced on activated tumor-associated DCs (TADCs) in vitro compared with their resting counterparts. This PD-1+ DC population was characterized by reduced secretion of cytokines (IL-12, TNF-α, and IL-1β) and dysfunctional induction of T cell proliferation and cytotoxic reaction. PD-1 blockade significantly reinvigorated PD-1+ DCs to release IL-12, TNF-α, and IL-1β compared with PD-1- DCs. TILs from samples with higher PD-1+ DC infiltration could be induced to achieve a greater killing effect of PD-1 blockade treatment. Our findings suggested a role for PD-1+ DCs in immune surveillance dysfunction and CC progression. PD-1+ DC density in the TME may serve as a diagnostic factor for predicting the optimal beneficiaries of PD-1/PD-L1 blockade immunotherapy in CC.

Role of FoxP3-positive regulatory T-cells in regressive and progressive cervical dysplasia

PURPOSE

Forkhead Box Protein 3 (FoxP3) is known as a key mediator in the immunosuppressive function of regulatory T-cells (Tregs). The aim of our study was to investigate whether FoxP3-positive Tregs have the potential to act as an independent predictor in progression as well as in regression of cervical intraepithelial neoplasia, especially in patients with intermediate cervical intraepithelial neoplasia (CIN II).

METHODS

Nuclear FoxP3 expression was immunohistochemically analysed in 169 patient samples (CIN I, CIN II with regressive course, CIN II with progressive course, CIN III). The median numbers were calculated for each slide and correlated with the histological CIN grade. Statistical analysis was performed by SPSS 26 (Mann-Whitney U test, Spearman's rank correlation).

RESULTS

An increased FoxP3 expression in CIN II with progression could be detected in comparison to CIN II with regression (p = 0.003). Total FoxP3 expression (epithelium and dysplasia-connected stroma) was higher in more advanced CIN grades (p < 0.001 for CIN I vs. CIN II; p = 0.227 for CIN II vs. CIN III). A positive correlation could be detected between FoxP3-positive cells in epithelium and total FoxP3 expression (Spearman's Rho: 0,565; p < 0.01).

CONCLUSION

Expression of FoxP3 could be a helpful predictive factor to assess the risks of CIN II progression. As a prognosticator for regression and progression in cervical intraepithelial lesions it might thereby help in the decision process regarding surgical treatment vs. watchful waiting strategy to prevent conisation-associated risks for patients in child-bearing age. In addition, the findings support the potential of Tregs as a target for immune therapy in cervical cancer patients.

Changes in peripheral lymphocyte populations in patients with advanced/recurrent ovarian cancer undergoing splenectomy during cytoreductive surgery

BACKGROUND

To investigate changes in peripheral lymphocyte subsets after splenectomy during cytoreductive surgery for advanced or recurrent ovarian cancers.

METHODS

We enrolled 83 patients with advanced or recurrent ovarian cancer who underwent cytoreductive surgery. Twenty patients who also underwent splenectomy were assigned to the splenectomy cohort and the rest were assigned to the non-splenectomy cohort. Flow cytometry was used to measure peripheral lymphocyte subsets consisting of T cells, regulatory T cells, natural killer cells, B cells, and activation antigens before and after surgery.

RESULTS

There was no difference in the number and distribution of peripheral lymphocyte subsets between the two cohorts before surgery. After surgery, we observed elevated levels of T cells (CD3⁺, CD3⁺CD8⁺) in the splenectomy cohort compared to those in the non-splenectomy cohort, and the difference was statistically significant. CD8⁺CD28⁺ T cells had a significant decreasing tendency (P = 0.011) while CD3⁺/HLA-DR⁺ T cells showed the opposite trend (P = 0.001) in the splenectomy cohort. The proportion of Tregs (P = 0.005) and B cells (P < 0.001) including CD3^-/HLA-DR⁺ B cells (P = 0.007) increased after surgery, and the absolute number of T cells and NK cells decreased to different extents (P < 0.001) in the non-splenectomy cohort. The post-operative percentage of CD8⁺CD28⁺ T cells was less than the pre-operative percentage (P = 0.022), which was similar to the splenectomy cohort. There was no significant difference in progression-free survival or overall survival between the groups after a median follow-up time of 41 months.

CONCLUSIONS

The changes in peripheral lymphocyte populations were different between patients with and those without splenectomy during cytoreductive surgery for ovarian cancers. T cells were increased and activated in the splenectomy cohort, whereas, B cells were increased and activated in the non-splenectomy cohort.

Small organic molecules accelerate the expansion of regulatory T cells

The regulatory T cells (T_reg cells) expressing CD4 + CD25 + FOXP3 + markers are indispensable for the initiation of immune homeostasis and tolerance to self-antigens in both mice and humans. A decrease in regulatory T cells leads to various autoimmune pathologies. Herein, we report three low molecular weight, small organic molecules as a new series of T_reg proliferators TRP-1-3. These small molecules were tested for their proliferative effect on regulatory T cells. It was found that TRP-1 (Oleracein E) strongly accelerates the T_reg proliferation in vitro in a concentration-dependent manner. The effect was evident for all subsets of T_reg cells tested, including naturally occurring, thymus-derived and peripherally-induced or adaptive T_reg, indicating an effect independent of the maturation site. Importantly, increased T_reg cells numbers by TRP-1 correlated with improved CD4 + CD25 + FOXP3 + expression in vitro, while propidium iodide-based staining showed low TRP-1-induced cytotoxicity. Molecular docking plus simulation studies of these TRP-1-3 with IL-2R, mTOR and TCR receptors suggest a TCR-based T_reg cells activation mechanism. Because of its high T_reg cells activities and low cellular cytotoxicity, TRP-1-3 may be useful in stimulating ex-vivo/in-vivo, T_reg cell-specific responses for therapeutic applications.

Erythropoietin administration expands regulatory T cells in patients with autoimmune hepatitis

OBJECTIVE

Autoimmune hepatitis (AIH) is a chronic liver disease associated with impaired regulatory T cell (Treg) number and function. Erythropoietin (EPO) is a kidney-produced erythropoietic hormone that has known immune-modulating effects, including Treg induction. Whether EPO administration increases Treg in patients with AIH is unknown.

METHODS

We treated six stable AIH patients with a single 1000 IU dose of EPO and comprehensively characterized changes in Treg overall and in Treg subsets before and at 4 and 12 weeks after treatment using mass cytometry (CyTOF) combined with an unbiased clustering approach (Phenograph) based on 22 Treg-relevant cell-surface markers.

RESULTS

EPO was well-tolerated and no patients showed significant changes in hematological parameters, liver enzymes, or IgG levels from baseline to 12 weeks following EPO administration. Total Treg and Treg/CD8⁺ T cell ratios significantly increased at 4 weeks and returned to baseline levels at 12 weeks after EPO injection. We identified 17 Treg subsets of which CD4⁺CD25^HICD127^NEG HLADR⁺ Treg had the highest increase and the most favorable Treg/CD8⁺ ratio upon EPO treatment. At 12 weeks after EPO administration, the HLADR⁺ Treg subset also returned to values comparable to those at baseline. Ex vivo assays documented that Treg were functional and the ones isolated at 12 weeks after EPO injection were significantly more suppressive than the ones isolated at baseline. In Treg-depleted assays, EPO did not show a significant effect on IFN-γ+, IL-2⁺, and IL-17⁺ CD4⁺ T cells.

CONCLUSION

In stable AIH patients, EPO increases overall Treg and particularly those expressing the high function marker HLA-DR. These results provide the rationale for future studies testing the hypothesis that EPO or EPO analogues improve outcomes of AIH patients by increasing Treg.

The combined action of monocytic myeloid-derived suppressor cells and mucosal-associated invariant T cells promotes the progression of cervical cancer

One of the most common promoters of the initiation and growth of the tumor is an immune disturbance. Numerous immune cells and inflammatory factors play a role in the tumor-immune microenvironment. However, few studies have investigated the correlation between these immunological events and clinical consequences in cervical cancer. We measured the levels of numerous inflammatory mediators and frequencies of regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs) and mucosal-associated invariant T (MAIT) cells in peripheral blood (PB) of cervical cancer patients. Cervical cancer patients showed elevated production of interleukin (IL)-18 and plasma C-C chemokine ligand (CCL) 3/5. Meanwhile, an accumulation of C-C chemokine receptor 5 (CCR5) monocytic (Mo)-MDSCs and Tregs was observed. The cervical cancer group displayed increased frequencies of CD8⁺ , CD4⁺ and highly activated CD38⁺ CD8⁺ MAIT cells, and reduction of double-negative (DN) and PD1(CD279⁺ ) DN MAIT cells. Importantly, it was demonstrated that MAIT cells were positively related to Mo-MDSCs. Furthermore, an elevated concentration of PD1(CD279⁺ ) DN MAIT cells was significantly related to increased progression-free survival of patients with cervical cancer. In conclusion, our study suggests that the combined action of Mo-MDSCs and MAIT cells might be associated with the progression of cervical cancer, and the frequency of DN MAIT cells in the peripheral blood mononuclear cells was associated with the survival benefit of patients.

Cervical Cancer: Emerging Immune Landscape and Treatment

Immune cells are essential for defending the body’s balance and have increasingly been implicated in controlling tumor growth. In cervical cancer (CC), the immune landscape is extensively connected with human papillomavirus (HPV) status. Recent insights from studies have revealed that as a result of infection with HPV, immune cell populations such as lymphocytes or monocytes change during carcinogenesis. Immune therapy, in particular checkpoint inhibitors, those targeting PD-1 or PD-L1, has shown promising efficacy. This article reviews the immune landscape and immunotherapy of CC.

Clinical significance of peripheral blood and tumor tissue lymphocyte subsets in cervical cancer patients

Background

Alterations in peripheral blood lymphocytes in cervical cancer have been reported, although conflicting views exist. The present study investigated the distributions of lymphocyte subsets in tumor tissue and peripheral blood samples from cervical cancer patients and precancerous lesion patients, and evaluated the correlations of lymphocyte subsets with clinicopathological and prognostic variables.

Methods

A total of 44 patients with stage IB1-IIA2 cervical cancer and 13 precancerous lesion patients were included. Lymphocytes were collected from the tumor tissue and the peripheral blood, and isolated by Lymphoprep density gradient centrifugation. The percentages of lymphocyte subsets were quantified by flow cytometry analysis, and the differences between lymphocyte subsets in the tumor tissue and peripheral blood were compared by SPSS. In addition, the relationships between lymphocyte subsets and clinicopathological and prognostic variables were analyzed.

Results

Our results revealed that the amount of total T lymphocytes, CD8+ T cells, granulocytes, pDCs, CD16+ monocytes and CD56^high NK cells were significantly higher in the tumor tissue than in the peripheral blood in the cervical cancer patients, while those of CD4+ T cells, CD4+/CD8+ cell ratio, rdT cells, BDCA1+ mDCs, total monocytes, CD14+ monocytes, NK cells and CD56^low NK cells exhibited the opposite trend (p < 0.05). The levels of total pDCs and BDCA1+ mDCs in the peripheral blood were significantly lower in the cervical cancer patients than in the precancerous lesion patients, while the proportion of CD16+ monocytes was elevated (p < 0.05). In addition, some lymphocyte subsets, especially CD4+ cells and CD8+ cells, and the CD4+/CD8+ cell ratio were closely associated with clinicopathological and prognostic parameters.

Conclusions

These results suggested that distinct alterations in infiltrating lymphocyte subsets occurred in the tumor and were associated with clinicopathological and prognostic parameters. Systemic impairment of the immune system may occur in the antitumor response of cervical cancer patients.