Immunoadjuvant Therapy Research Articles

Disrupting Smad3 potentiates immunostimulatory function of NK cells against lung carcinoma by promoting GM-CSF production

Through Smad3-dependent signalings, transforming growth factor-β (TGF-β) suppresses the development, maturation, cytokine productions and cytolytic functions of NK cells in cancer. Silencing Smad3 remarkably restores the cytotoxicity of NK-92 against cancer in TGF-β-rich microenvironment, but its effects on the immunoregulatory functions of NK cells remain obscure. In this study, we identified Smad3 functioned as a transcriptional repressor for CSF2 (GM-CSF) in NK cells. Therefore, disrupting Smad3 largely mitigated TGF-β-mediated suppression on GM-CSF production by NK cells. Furthermore, silencing GM-CSF in Smad3 knockout NK cells substantially impaired their anti-lung carcinoma effects. In-depth study demonstrated that NK-derived GM-CSF strengthened T cell immune responses by stimulating dendritic cell differentiation and M1 macrophage polarization. Meanwhile, NK-derived GM-CSF promoted the survival of neutrophils, which in turn facilitated the terminal maturation of NK cells, and subsequently boosted NK-cell mediated cytotoxicity against lung carcinoma. Thus, Smad3-silenced NK-92 (NK-92-S3KD) may serve as a promising immunoadjuvant therapy with clinical translational value given its robust cytotoxicity against malignant cells and immunostimulatory functions to reinforce the therapeutic effects of other immunotherapies.

Exploring the role of antioxidants in sepsis-associated oxidative stress: a comprehensive review.

Sepsis is a potentially fatal condition characterized by organ dysfunction caused by an imbalanced immune response to infection. Although an increased inflammatory response significantly contributes to the pathogenesis of sepsis, several molecular mechanisms underlying the progression of sepsis are associated with increased cellular reactive oxygen species (ROS) generation and exhausted antioxidant pathways. This review article provides a comprehensive overview of the involvement of ROS in the pathophysiology of sepsis and the potential application of antioxidants with antimicrobial properties as an adjunct to primary therapies (fluid and antibiotic therapies) against sepsis. This article delves into the advantages and disadvantages associated with the utilization of antioxidants in the therapeutic approach to sepsis, which has been explored in a variety of animal models and clinical trials. While the application of antioxidants has been suggested as a potential therapy to suppress the immune response in cases where an intensified inflammatory reaction occurs, the use of multiple antioxidant agents can be beneficial as they can act additively or synergistically on different pathways, thereby enhancing the antioxidant defense. Furthermore, the utilization of immunoadjuvant therapy, specifically in septic patients displaying immunosuppressive tendencies, represents a promising advancement in sepsis therapy.

Immunotherapy with STING and TLR9 agonists promotes synergistic therapeutic efficacy with suppressed cancer-associated fibroblasts in colon carcinoma.

The innate immune sensing of nucleic acids using effective immunoadjuvants is critical for increasing protective immune responses against cancer. Stimulators of interferon genes (STING) and toll-like receptor 9 (TLR9) agonists are considered promising candidates in several preclinical tumor models with the potential to be used in clinical settings. However, the effects of such treatment on tumor stroma are currently unknown. In this study, we investigated the immunotherapeutic effects of ADU-S100 as a STING agonist and CpG ODN1826 as a TLR9 agonist in a preclinical model of colon carcinoma. Tumor-bearing mice were treated intratumorally on days 10 and 16 post-tumor inoculation with ADU-S100 and CpG ODN1826. Cytokine profiles in the tumor and spleen, tumor cell apoptosis, the infiltration of immune cells, and cancer-associated fibroblasts (CAFs) in the tumor microenvironment (TME) were evaluated to identify the immunological mechanisms after treatment. The powerful antitumor activity of single and combination treatments, the upregulation of the expression of pro-inflammatory cytokines in the tumor and spleen, and the recruitment and infiltration of the TME by immune cells revealed the synergism of immunoadjuvants in the eradication of the colon carcinoma model. Remarkably, the significant downregulation of CAFs in the TME indicated that suppression of tumorigenesis occurred after immunoadjuvant therapy. The results illustrate the potential of targeting the STING and TLR9 pathways as powerful immunoadjuvants in the treatment of preclinical colon carcinoma and the possibility of harnessing these pathways in future therapeutic approaches.

Stimulating Antitumoral Immunity by Percutaneous Cryoablation and Combination Immunoadjuvant Therapy in a Murine Model of Hepatocellular Carcinoma

PurposeTo test the hypothesis that antitumoral immunity can be induced after cryoablation (cryo) of hepatocellular carcinoma (HCC) through coadministration of the immunostimulant CpG and an immune checkpoint (programmed cell death 1 [PD-1]) inhibitor. Materials and MethodsSixty-three immunocompetent C57BL/6J mice were generated with 2 orthotopic HCC tumor foci: 1 for treatment and 1 to observe for antitumoral immunity. Tumors were treated with incomplete cryo alone or intratumoral CpG and/or a PD-1 inhibitor. The primary endpoint was death or when the following criteria for sacrifice were met: tumor > 1 cm (determined using ultrasound) or moribund state. Antitumoral immunity was assessed using flow cytometry and histology (tumor and liver) as well as enzyme-linked immunosorbent assay (serum). Analysis of variance was used for statistical comparisons. ResultsAt 1 week, the nonablated satellite tumor growth was reduced by 1.9-fold (P = .047) in the cryo + CpG group and by 2.8-fold (P = .007) in the cryo + CpG + PD-1 group compared with that in the cryo group. Compared with cryo alone, the time to tumor progression to endpoints was also prolonged for cryo + CpG + PD-1 and cryo + CpG mice, with log-rank hazard ratios of 0.42 (P = .031) and 0.27 (P < .001), respectively. Flow cytometry and histology showed increased cytotoxic T-cell infiltration (P = .002) and serum levels of the proinflammatory cytokine interferon-γ (P = .015) in tumors and serum of cryo + CpG mice compared with those in tumors and serum of mice treated with cryo alone. High serum levels of the anti-inflammatory cytokine tumor growth factor-β and the proangiogenesis chemokine C-X-C motif chemokine ligand 1 were correlated with a shorter time to endpoints and faster tumor growth. ConclusionsCryo combined with the immunostimulant CpG promoted cytotoxic T-cell infiltration into tumors, slowed tumor growth, and prolonged the time to progression to endpoints in an aggressive murine HCC model.

Fueling sentinel node via reshaping cytotoxic T lymphocytes with a flex-patch for post-operative immuno-adjuvant therapy

Clinical updates suggest conserving metastatic sentinel lymph nodes (SLNs) of breast cancer (BC) patients during surgery; however, the immunoadjuvant potential of this strategy is unknown. Here we leverage an immune-fueling flex-patch to animate metastatic SLNs with personalized antitumor immunity. The flex-patch is implanted on the postoperative wound and spatiotemporally releases immunotherapeutic anti-PD-1 antibodies (aPD-1) and adjuvants (magnesium iron-layered double hydroxide, LDH) into the SLN. Genes associated with citric acid cycle and oxidative phosphorylation are enriched in activated CD8+ T cells (CTLs) from metastatic SLNs. Delivered aPD-1 and LDH confer CTLs with upregulated glycolytic activity, promoting CTL activation and cytotoxic killing via metal cation-mediated shaping. Ultimately, CTLs in patch-driven metastatic SLNs could long-termly maintain tumor antigen-specific memory, protecting against high-incidence BC recurrence in female mice. This study indicates a clinical value of metastatic SLN in immunoadjuvant therapy.

Neoadjuvant Immunotherapy Combined with Chemotherapy for Local Advanced Non-Small-Cell Lung Cancer in a Patient with a History of Breast Cancer: A Case Report

Durvalumab consolidation therapy is the standard treatment after concurrent chemoradiotherapy for patients with surgically unresectable stage IIIA (N2) non-small-cell lung cancer (NSCLC). Neoadjuvant therapy followed by surgery could reduce locoregional and distant recurrence and improve the survival rate for surgically resectable NSCLC. However, the value of neoadjuvant therapy in locally advanced potentially resectable NSCLC remains controversial. Herein, we report a locally advanced potentially resectable NSCLC case with a history of breast cancer who achieved a pathologic complete response (pCR) after preoperative treatment with pembrolizumab and chemotherapy. A 50-year-old woman developed squamous cell carcinoma (SCC) (left lower lobe of the lung, stage IIIA-N2) after two years of chemotherapy and anti-HER2 therapy following a diagnosis of HER2-overexpressing breast cancer. Surgical resection was attempted despite an MDT classification as unamenable to curative surgical resection. After two cycles of neoadjuvant chemotherapy combined with anti-PD1 immunotherapy, the tumor significantly shrank, then the patient underwent a left lower lobectomy. Complete resection with negative margins (R0 resection) was achieved in the patient. The patient experienced grade 1–2 adverse effects and no grade 3 or worse adverse effects occurred. Cardiotoxicity did not occur in the patient despite prior anti-HER2 treatment for breast cancer. Our case study contributes to the existing evidence on the feasibility, efficacy, and safety of neoadjuvant immunotherapy combined with chemotherapy in locally advanced unresectable NSCLC. Furthermore, future studies are needed to determine which patients can benefit from immunoadjuvant therapy and the duration and course of preoperative and postoperative immunotherapy.

Photoimmunotherapy: A New Paradigm in Solid Tumor Immunotherapy

In recent years, the incidence of cancer has been increasing worldwide. Conventional cancer treatments include surgery, chemotherapy, and radiation, which mostly kill tumor cells at the expense of normal and immune cells. Although immunotherapy is an accurate, rapid, efficient tumor immune treatment, it causes serious adverse reactions, such as cytokine release syndrome (CRS) and neurotoxicity. Therefore, there is an urgent need to develop an effective and nontoxic procedure for immunotherapy. The clinical combination of phototherapy and immunoadjuvant therapy can induce immunogenic cell death and enhance antigen presentation synergy. It also causes a systemic antitumor immune response to manage residual tumors and distant metastases. Photoimmunotherapy (PIT) is a tumor treatment combining phototherapy with immunotherapy based on injecting a conjugate photosensitizer (IR700) and a monoclonal antibody (mAb) to target an expressed antigen on the tumor surface. This combination can enhance the immune response ability, thus having a good effect on the treatment of residual tumor and metastatic cancer. In this review, we summarize the recent progress in photoimmunotherapy, including photoimmunoconjugate (PIC), the activation mechanism of immunogenic cell death (ICD), the combination therapy model, opportunities and prospects. Specifically, we aim to provide a promising clinical therapy for solid tumor clinical transformation.

IL-7 Immunotherapy in a Nonimmunocompromised Patient With Intractable Fungal Wound Sepsis.

A nonimmunocompromised patient developed life-threatening soft tissue infection with Trichosporon asahii, Fusarium, and Saksenaea that progressed despite maximum antifungal therapies and aggressive debridement. Interleukin-7 immunotherapy resulted in clinical improvement, fungal clearance, reversal of lymphopenia, and improved T-cell function. Immunoadjuvant therapies to boost host immunity may be efficacious in life-threatening fungal infections.

Cancer photo-immunotherapy: from bench to bedside.

Targeted therapy and immunotherapy in combination is considered the ideal strategy for treating metastatic cancer, as it can eliminate the primary tumors and induce host immunity to control distant metastases. Phototherapy, a promising targeted therapy, eradicates primary tumors using an appropriate dosage of focal light irradiation, while initiating antitumor immune responses through induced immunogenic tumor cell death. Recently, phototherapy has been employed to improve the efficacy of immunotherapies such as chimeric antigen receptor T-cell therapy and immune checkpoint inhibitors. Phototherapy and immunoadjuvant therapy have been used in combination clinically, wherein the induced immunogenic cell death and enhanced antigen presentation synergy, inducing a systemic antitumor immune response to control residual tumor cells at the treatment site and distant metastases. This review summarizes studies on photo-immunotherapy, the combination of phototherapy and immunotherapy, especially focusing on the development and progress of this unique combination from a benchtop project to a promising clinical therapy for metastatic cancer.

Nanoscale Metal-Organic Frameworks for Cancer Immunotherapy.

Cancer immunotherapy, particularly checkpoint blockade immunotherapy (CBI), has revolutionized the treatment of some cancers by reactivating the antitumor immunity of hosts with durable response and manageable toxicity. However, many cancer patients with low tumor antigen exposure and immunosuppressive tumor microenvironments do not respond to CBI. A variety of methods have been investigated to reverse immunosuppressive tumor microenvironments and turn "cold" tumors "hot" with the goal of extending the therapeutic benefits of CBI to a broader population of cancer patients. Immunostimulatory adjuvant treatments, such as cancer vaccines, photodynamic therapy (PDT), radiotherapy (RT), radiotherapy-radiodynamic therapy (RT-RDT), and chemodynamic therapy (CDT), promote antigen presentation and T cell priming and, when used in combination with CBI, reactivate and sustain systemic antitumor immunity. Cancer vaccines directly provide tumor antigens, while immunoadjuvant therapies such as PDT, RT, RT-RDT, and CDT kill cancer cells in an immunogenic fashion to release tumor antigens in situ. Direct administration of tumor antigens or indirect intratumoral immunoadjuvant therapies as in situ cancer vaccines initiate the immuno-oncology cycle for antitumor immune response.With the rapid growth of cancer nanotechnology in the past two decades, a large number of nanoparticle platforms have been studied, and some nanomedicines have been translated into clinical trials. Nanomedicine provides a promising strategy to enhance the efficacy of immunoadjuvant therapies to potentiate cancer immunotherapy. Among these nanoparticle platforms, nanoscale metal-organic frameworks (nMOFs) have emerged as a unique class of porous hybrid nanomaterials with metal cluster secondary building units and organic linkers. With molecular modularity, structural tunability, intrinsic porosity, tunable stability, and biocompatibility, nMOFs are ideally suited for biomedical applications, particularly cancer treatments.In this Account, we present recent breakthroughs in the design of nMOFs as nanocarriers for cancer vaccine delivery and as nanosensitizers for PDT, CDT, RT, and RT-RDT. The versatility of nMOFs allows them to be fine-tuned to effectively load tumor antigens and immunoadjuvants as cancer vaccines and significantly enhance the local antitumor efficacy of PDT, RT, RT-RDT, and CDT via generation of reactive oxygen species (ROS) for in situ cancer vaccination. These nMOF-based treatments are further combined with cancer immunotherapies to elicit systemic antitumor immunity. We discuss novel strategies to enhance light tissue penetration and overcome tumor hypoxia in PDT, to increase energy deposition and ROS diffusion in RT, to combine the advantages of PDT and RT to enable RT-RDT, and to trigger CDT by hijacking aberrant metabolic processes in tumors. Loading nMOFs with small-molecule drugs such as an indoleamine 2,3-dioxygenase inhibitor, the toll-like receptor agonist imiquimod, and biomacromolecules such as CpG oligodeoxynucleotides and anti-CD47 antibody synergizes with nMOF-based radical therapies to enhance their immunotherapeutic effects. Further combination with immune checkpoint inhibitors activates systemic antitumor immune responses and elicits abscopal effects. With structural and compositional tunability, nMOFs are poised to provide a new clinically deployable nanotechnology platform to promote immunostimulatory tumor microenvironments by delivering cancer vaccines, mediating PDT, enhancing RT, enabling RT-RDT, and catalyzing CDT and potentiate cancer immunotherapy.

Roles of PD-1 and PD-L1 receptors in the development of systemic inflammatory response and immunoadjuvant therapy

The modern view of systemic inflammatory response revolves around the fact that the key pathophysiological link is immunosuppression rather than the initial hyperinflammatory phase as previously supposed. Immunosuppression in critically induced systemic inflammatory response syndrome is associated with increased susceptibility of patients to secondary nosocomial infections and increased probability of progression to multiple organ failure. The role of programmed cell death protein 1 (PD-1) has been investigated in the context of systemic inflammatory response from the standpoint of its participation in the development of immunosuppression. One of the mechanisms of immunosuppression is the exhaustion of T-cells mediated by inhibitory PD-1 receptors. In the body, the PD-1/programmed death-ligand 1 (PD-L1) pathway regulates autoimmunity, tumour immunity, transplant immunity, allergies and immunopathology. This review summarises the results of experimental studies demonstrating that blocking the interaction of PD-1 with its PD-L1 ligand recovers T-cell dysfunction and improves survival rates in animal models of sepsis. Moreover, a clinical case of the use of anti-PD-1 therapy that led to improvement in the status of a critically ill patient is described. Undesirable side effects of this therapeutic approach are also evaluated. Meanwhile, immune checkpoint inhibitors have been introduced into clinical practice to treat certain forms of cancer. Increased expression of PD-1 receptors in systemic inflammatory response syndrome is may thus be a prognostic marker. Received 2 August 2019. Accepted 30 October 2019. Funding: The work is supported by a grant of the President of the Russian Federation for leading scientific schools НШ-2696.2018.7 “Prediction and preventive intensive care of persistent multiple organ failure.” Conflict of interest: Authors declare no conflict of interest.

Evaluation of Oncolytic Viral Therapy Combined with or without Artificial Immunoadjuvant Cell Therapy in Immunocompetent Mouse Tumor Models

Oncolytic viruses have a great potential to provide clinical improvement for cancer patients who do not respond to conventional therapies. The mechanisms of action include direct infection, immune-mediated cell death, and vascular collapse. We previously reported that a miRNA-regulated, thymidine kinase-deleted vaccinia virus (MDVV) specifically infects multiple myeloma (MM) cells and showed that the intravenous injection of MDVV significantly prolonged survival of severe combined immunodeficiency mice harboring a subcutaneous human RPMI8226 MM tumor (Blood 2014:124:2082, Mol Ther Oncolytics 2017;6:57). Although it was highly effective, there remained to be confirmed whether the MDVV would be similarly effective in the immunocompetent setting. To address this question, we performed several in vivo infection using immunocompetent C57BL/6 (B6) models.A vaccinia virus (VV) strain LC16, which was derived from the Lister strain, was widely used in 1970s for the smallpox eradication program with no severe adverse effect. Because its safety is robust, we used the LC16 for the backbone of the MDVV. To improve its safety and tumor specificity, we deleted viral thymidine kinase gene, and introduced miRNA (let-7a)-target sequences into the critical viral B5R gene. Because let-7a is abundant in normal differentiated tissues, and the endogenous let-7a down-regulates viral B5R gene, the MDVV becomes far more tumor specific (Mol Ther Oncolytics 2017;6:57).To observe whether the MDVV protects immunocompetent mice from MM, we generated a mouse MM model by transplanting 1x10^6 Vk*Myc tumor cells into syngeneic B6 mice. After confirming M-proteins in the serum, 1x10^7 pfu of MDVV was injected intravenously. Contrary to our expectation, we could not observe a clearly infected region, nor a prolongation of survival of these mice; probably due to difference in infectivity between species. Although mouse derived cell lines are generally insensitive to vaccinia virus as compared with human cell lines, a mouse lung carcinoma cell line 3LL showed a relatively high infectivity to VV in our screening in vitro infection experiment (Figure), therefore we used the B6/3LL subcutaneous tumor model instead of B6/Vk*Myc model.The B6/3LL mice were injected with mock or 1x10^7 pfu MDVV intravenously when the subcutaneous tumor became more than 5 mm in diameter. Although viral signal (determined by in vivo imaging using luciferase) disappeared 3 days after infection, the therapeutic benefit had remained, and prolongation of survival was observed Because natural killer (NK) cells were thought to play in the clearance of VV in the B6 mice, we attempted to extend the duration of infection by depleting NK cells using anti-asialo GM1 antibody, which, we thought, enhances viral oncolytic activity. As expected, we observed a persistent viral signal for up to 2 weeks in anti-asialo GM1 antibody treated B6/3LL mice. However, the anti-tumor effect seen with anti-asialo GM1 antibody was rather milder than that of without anti-asialo GM1 antibody, indicating the importance of NK activities in anti-tumor immunity.Based on this finding, we, in reverse, tried to stimulate the anti-tumor immunity using artificial immunoadjuvant cells co-expressing CD1d and tumor antigen/GM-CSF fusion protein. The CD1d is one of non-classical MHC molecules and is involved in the presentation of lipid antigens. When α-GlaCer is loaded on the CD1d, it activates natural killer T (NKT) cells through the interaction with invariant T cell receptor on NKT cells. When activated, NKT cells produce Th1 and Th2 cytokines, and activate NK cells. GM-CSF stimulates antigen-presenting cells (APCs), and fusion proteins of tumor antigen and GM-CSF are more efficiently taken up by APCs than tumor antigen alone (Nature 1993, 362:755). We generated the artificial immunoadjuvant cells by transducing 3LL tumor cells with lentiviral vectors expressing CD1d and ovalbumin (OVA)/GM-CSF fusion protein. After loading with α-GlaCer, the immunoadjuvant cells were irradiated with 50Gy, and injected intravenously into B6/3LL-OVA mice. We observed a significant reduction in tumor mass and prolongation of survival as compared with mock-injected mice. Currently, we are exploring the optimal setting of combination with MDVV virotherapy and immunoadjuvant cell therapy. In this meeting, we will present these results. DisclosuresNo relevant conflicts of interest to declare.

Low Interleukin-7 Receptor Messenger RNA Expression Is Independently Associated With Day 28 Mortality in Septic Shock Patients.

Septic shock is the primary cause of death in ICUs. A better comprehension of its pathophysiology, in particular, the immune alteration mechanisms, opened new therapeutic perspectives such as the recombinant interleukin-7. The use of biomarkers could improve the identification of eligible patients for this therapy. The soluble form of the interleukin-7 appears as a promising candidate in this regard since an association between its high plasmatic level and mortality in critically ill patients has been demonstrated. Because there are no data available on the transcriptional regulation of the interleukin-7 receptor in such patients, this study aimed to explore the expression level of different interleukin-7 receptor transcripts after septic shock and evaluate their association with mortality. Retrospective discovery cohort (30 patients) and validation cohort (177 patients). Two French ICUs (discovery study) and six French ICUs (validation study). Adult septic shock patients. None. The quantification of several interleukin-7 receptor transcripts using specific reverse transcription quantitative polymerase chain reaction designs allowed for global evaluation of interleukin-7 receptor gene expression in whole blood. In the discovery cohort, all interleukin-7 receptor transcripts studied were expressed at lower levels in septic shock patients than in healthy volunteers. Interleukin-7 receptor gene expression at day 3 after septic shock diagnosis was associated with day 28 mortality. Patients at a lower risk of death showed higher expression levels. These results were confirmed in the independent validation cohort. Interestingly, using a threshold obtained on the discovery cohort, we observed in the validation cohort a high negative predictive value for day 28 mortality for the transcript encoding the membrane form of interleukin-7 receptor (0.86; 95% CI, 0.79-0.93). Interleukin-7 receptor transcripts appear as biomarkers of impaired adaptive immune response in septic shock patients and as a promising tool for patient stratification in clinical trials evaluating immunoadjuvant therapies.

Immunoadjuvant therapy in sepsis: novel strategies for immunosuppressive sepsis coming down the pike.

Recent efforts have focused on immunoadjuvant therapies for sepsis. The host inflammatory response consequent to initial exposure to pathogens is often followed by anti‐inflammatory forces, resulting in increased morbidity and mortality in such critically ill patients. In the subacute stage of sepsis, apoptosis (type I programmed cell death) and subsequently autophagy (type II programmed cell death) have been attracting recent research interest. Although many patients may die during the initial cytokine storm, those who survive this phase might acquire defining characteristics of profound immunosuppression, including failure to clear the primary infection, development of secondary opportunistic infections, and reactivation of latent viruses. Both types of cell death are currently thought to be associated with this subacute immunosuppressive phase of sepsis, and acceleration of autophagy might alleviate immunosuppression through regulation of apoptosis of key immune effector cells. Programmed cell death 1 (PD‐1) and its corresponding ligand play a major pathological role in immunosuppression not only in cancer but also in sepsis. Positive costimulatory pathways in T cells, such as CD28 signaling, permit the effector T cell to expand, persist, and effectively clear antigen. However, PD‐1 is a negative costimulatory pathway on T cells that broadly enhances immunosuppressive signals across the innate and adaptive immune system. To counter this immunosuppression in sepsis, checkpoint blockade has garnered attention in an area of clinical research. In this review, we introduce some approaches of immunotherapy using anti‐PD‐1 antibody in infectious diseases and share our future perspectives.

Mechanisms of sepsis-induced immunosuppression and immunological modification therapies for sepsis.

Surgical injury can be a life‐threatening complication, not only due to the injury itself, but also due to immune responses to the injury and subsequent development of infections, which readily result in sepsis. Sepsis remains the leading cause of death in most intensive care units. Unfavorable outcomes of several high‐profile trials in the treatment of sepsis have led researchers to state that sepsis studies need a new direction. The immune response that occurs during sepsis is characterized by a cytokine‐mediated hyper‐inflammatory phase, which most patients survive, and a subsequent immunosuppressive phase. Therefore, therapies that improve host immunity might increase the survival of patients with sepsis. Many mechanisms are responsible for sepsis‐induced immunosuppression, including apoptosis of immune cells, increased regulatory T cells and expression of programmed cell death 1 on CD4+ T cells, and cellular exhaustion. Immunomodulatory molecules that were recently identified include interleukin‐7, interleukin‐15, and anti‐programmed cell death 1. Recent studies suggest that immunoadjuvant therapy is the next major advance in sepsis treatment.

Restoration of T Cell function in multi-drug resistant bacterial sepsis after interleukin-7, anti-PD-L1, and OX-40 administration.

BackgroundMultidrug resistant (MDR) bacterial pathogens are a serious problem of increasing importance facing the medical community. MDR bacteria typically infect the most immunologically vulnerable: patients in intensive care units, patients with extensive comorbidities, oncology patients, hemodialysis patients, and other immune suppressed individuals are likely to fall victim to these pathogens. One promising novel approach to treatment of MDR bacteria is immuno-adjuvant therapy to boost patient immunity. Success with this strategy would have the major benefit of providing protection against a number of MDR pathogens.ObjectivesThis study had two main objectives. First, immunophenotyping of peripheral blood mononuclear cells from patients with sepsis associated with MDR bacteria was performed to examine for findings indicative of immunosuppression. Second, the ability of three immuno-adjuvants with distinct mechanisms of action to reverse CD4 and CD8 T cell dysfunction, a pathophysiological hallmark of sepsis, was evaluated.ResultsSeptic patients with MDR bacteria had increased expression of the inhibitory receptor PD-1 and its ligand PD-L1 and decreased monocyte HLA-DR expression compared to non-septic patients. All three immuno-adjuvants, IL-7, anti-PD-L1, and OX-40L, increased T cell production of IFN-γ in a subset of septic patients with MDR bacteria: IL-7 was most efficacious. There was a strong trend toward increased mortality in patients whose T cells failed to increase IFN-γ production in response to the three treatments.ConclusionImmuno-adjuvant therapy reversed T cell dysfunction, a key pathophysiological mechanism in septic patients with MDR bacteria.

Low-molecular-weight polysaccharides from Agaricus blazei Murrill modulate the Th1 response in cancer immunity.

To assess the effect of low-molecular-weight polysaccharides from Agaricus blazei Murrill (ABP-AW1) as an immunoadjuvant therapy for type 1 T-helper (Th1) responses in tumorigenesis, C57BL/6 mice were inoculated subcutaneously with ovalbumin (E.G7-OVA). After 3, 10 and 17 days, the mice were immunized with PBS, OVA alone, or OVA and ABP-AW1, at low (50 µg), intermediate (100 µg) or high (200 µg) doses. Tumor growth was examined and compared among the groups, as were the following parameters: Splenocyte viability/proliferation, peripheral blood CD4+/CD8+ T cell ratio, serum OVA-specific IgG1 and IgG2b, secretion of interleukin (IL)-2 and interferon (IFN)-γ, and IFN-γ production on a single cell level from cultured splenocytes. Tumor growth in mice treated with OVA and ABP-AW1 (100 or 200 µg) was significantly slower, compared with in the other groups at the same time-points. OVA with 100 or 200 µg ABP-AW1 was associated with a higher number of total splenocytes, a higher ratio of peripheral blood CD4+/CD8+ T-lymphocytes, higher serum levels of OVA-specific Th1-type antibody IgG2b and greater secretion of the Th1 cytokines IL-1 and IFN-γ from splenocytes. ABP-AW1 is a promising immunoadjuvant therapy candidate, due to its ability to boost the Th1 immune response when co-administered with a cancer vaccine intended to inhibit cancer progression.

Development and validation of immune dysfunction score to predict 28-day mortality of sepsis patients.

BackgroundSepsis-induced immune dysfunction ranging from cytokines storm to immunoparalysis impacts outcomes. Monitoring immune dysfunction enables better risk stratification and mortality prediction and is mandatory before widely application of immunoadjuvant therapies. We aimed to develop and validate a scoring system according to patients’ immune dysfunction status for 28-day mortality prediction.MethodsA prospective observational study from a cohort of adult sepsis patients admitted to ICU between August 2013 and June 2016 at Kaohsiung Chang Gung Memorial Hospital in Taiwan. We evaluated immune dysfunction status through measurement of baseline plasma Cytokine levels, Monocyte human leukocyte-DR expression by flow cytometry, and stimulated immune response using post LPS stimulated cytokine elevation ratio. An immune dysfunction score was created for 28-day mortality prediction and was validated.ResultsA total of 151 patients were enrolled. Data of the first consecutive 106 septic patients comprised the training cohort, and of other 45 patients comprised the validation cohort. Among the 106 patients, 21 died and 85 were still alive on day 28 after ICU admission. (mortality rate, 19.8%). Independent predictive factors revealed via multivariate logistic regression analysis included segmented neutrophil-to-monocyte ratio, granulocyte-colony stimulating factor, interleukin-10, and monocyte human leukocyte antigen-antigen D–related levels, all of which were selected to construct the score, which predicted 28-day mortality with area under the curve of 0.853 and 0.789 in the training and validation cohorts, respectively.ConclusionsThe immune dysfunction scoring system developed here included plasma granulocyte-colony stimulating factor level, interleukin-10 level, serum segmented neutrophil-to-monocyte ratio, and monocyte human leukocyte antigen-antigen D–related expression appears valid and reproducible for predicting 28-day mortality.

Novel Approach in Monocyte Intracellular TNF Measurement: Application to Sepsis-Induced Immune Alterations.

The monitoring of septic shock induced immunosuppression has been proposed to identify patients who could benefit from specific immunoadjuvant therapies. Among potential biomarkers to monitor immunological status, functional testing remains the gold standard because it directly measures the capacity of a cell population to respond to an immune challenge. We investigated a new approach in intracellular staining for flow cytometry to measure tumor necrosis factor (iTNF) produced in vitro by monocytes in response to lipopolysaccharide. Observational study in intensive care unit and immunology laboratory of a university medical center. Sixteen septic shock patients and eight control subjects were included. Monocyte iTNF was determined by flow cytometry in whole blood and completed in 2.5 h according to a no-wash, no centrifuge procedure. Lipopolysaccharide challenge induced a tremendous expression of iTNF that was statistically more pronounced in controls than in patients. This was observed when results were expressed as medians of fluorescence intensity (median: 16.1 [IQR: 14.5-19.1] vs. 5 [4.0-8.0], P = 0.0001) or as percentages of positive cells (99.7 [99.6-99.8] vs. 85 [74-97], P = 0.0001). iTNF expression was correlated to monocyte HLA-DR expression in patients and controls. These preliminary results illustrate the feasibility of immune functional testing on a routine manner in septic shock patients. They now deserve to be widely assessed and validated in various intensive care unit conditions. This could be a major step to characterize the rapidly changing immune response overtime and thus permit personalized medicine.

Interleukin 7 immunotherapy improves host immunity and survival in a two-hit model of Pseudomonas aeruginosa pneumonia.

Patients with protracted sepsis develop impaired immunity, which predisposes them to acquiring secondary infections. One of the most common and lethal secondary infections is Pseudomonas aeruginosa pneumonia. Immunoadjuvant therapy is a promising approach to reverse sepsis-induced immunosuppression and improve morbidity and mortality from secondary infections. Interleukin-7 is an immunoadjuvant that improves survival in clinically relevant animal models of polymicrobial peritonitis and in fungal sepsis. This study investigated the effect of recombinant human interleukin-7 (rhIL-7) on survival in a 2-hit model of sublethal cecal ligation and puncture followed by P. aeruginosa pneumonia. Potential immunologic mechanisms responsible for the rhIL-7 putative beneficial effect were also examined, focusing on IL-17, IL-22, IFN-γ, and TNF-α, cytokines that are critical in the control of sepsis and pulmonary Pseudomonas infections. Results showed that rhIL-7 was highly effective in preventing P. aeruginosa-induced death, i.e., 92% survival in rhIL-7-treated mice versus 56% survival in control mice. rhIL-7 increased absolute numbers of immune effector cells in lung and spleen and ameliorated the sepsis-induced loss of lung innate lymphoid cells (ILCs). rhIL-7 also significantly increased IL-17-, IFN-γ-, and TNF-α-producing lung ILCs and CD8 T cells as well as IFN-γ- and TNF-α-producing splenic T cell subsets and ILCs. Furthermore, rhIL-7 enhanced NF-κB and STAT3 signaling in lungs during sepsis and pneumonia. Given the high mortality associated with secondary P. aeruginosa pneumonia, the ability of rhIL-7 to improve immunity and increase survival in multiple animal models of sepsis, and the remarkable safety profile of rhIL-7, clinical trials with rhIL-7 should be considered.