IL-2 mediates NK cell proliferation but not hyperactivity

IL-2-mediated hepatotoxicity: knowledge gap identification based on the irAOP concept

Drug-induced hepatotoxicity constitutes a major reason for non-approval and post-marketing withdrawal of pharmaceuticals. In many cases, preclinical models lack predictive capacity for hepatic damage in humans. A vital concern is the integration of immune system effects in preclinical safety assessment. The immune-related Adverse Outcome Pathway (irAOP) approach, which is applied within the Immune Safety Avatar (imSAVAR) consortium, presents a novel method to understand and predict immune-mediated adverse events elicited by pharmaceuticals and thus targets this issue. It aims to dissect the molecular mechanisms involved and identify key players in drug-induced side effects. As irAOPs are still in their infancy, there is a need for a model irAOP to validate the suitability of this tool. For this purpose, we developed a hepatotoxicity-based model irAOP for recombinant human IL-2 (aldesleukin). Besides producing durable therapeutic responses against renal cell carcinoma and metastatic melanoma, the boosted immune activation upon IL-2 treatment elicits liver damage. The availability of extensive data regarding IL-2 allows both the generation of a comprehensive putative irAOP and to validate the predictability of the irAOP with clinical data. Moreover, IL-2, as one of the first cancer immunotherapeutics on the market, is a blueprint for various biological and novel treatment regimens that are under investigation today. This review provides a guideline for further irAOP-directed research in immune-mediated hepatotoxicity.

Cytokine and chemokine profiles in women with endometriosis, polycystic ovary syndrome, and unexplained infertility

Numerous factors (including immunological, congenital, hormonal, and morphological disorders) can lead to infertility. In this regard, 3 specific diseases associated with infertility are discussed in this review study (i.e., polycystic ovary syndrome [PCOS], endometriosis [EMS], and unexplained infertility [UI]). PCOS is a common endocrine disorder characterized by chronic low-grade inflammation, and EMS is a benign disease characterized by the presence of ectopic endometrial tissue. UI refers to couples who are unable to conceive for no known reason. Conception and pregnancy are significantly affected by the immune system; in this regard, chemokines and cytokines play important roles in the regulation of immune responses. Patients with PCOS, EMS, and UI have altered cytokine and chemokine profiles, suggesting that dysregulation of these molecules may contribute to infertility in these conditions. Accordingly, the issue of infertility is addressed in this review study, a condition that affects approximately 16% of couples worldwide.

Overexpressing S100A9 ameliorates NK cell dysfunction in estrogen receptor-positive breast cancer

BACKGROUND

Estrogen receptor (ER) positive human epidermal growth factor receptor 2 (HER2) negative breast cancer (ER+/HER2-BC) and triple-negative breast cancer (TNBC) are two distinct breast cancer molecular subtypes, especially in tumor immune microenvironment (TIME). The TIME of TNBC is considered to be more inflammatory than that of ER+/HER2-BC. Natural killer (NK) cells are innate lymphocytes that play an important role of tumor eradication in TME. However, studies focusing on the different cell states of NK cells in breast cancer subtypes are still inadequate.

METHODS

In this study, single-cell mRNA sequencing (scRNA-seq) and bulk mRNA sequencing data from ER+/HER2-BC and TNBC were analyzed. Key regulator of NK cell suppression in ER+/HER2-BC, S100A9, was quantified by qPCR and ELISA in MCF-7, T47D, MDA-MB-468 and MDA-MB-231 cell lines. The prognosis predictability of S100A9 and NK activation markers was evaluated by Kaplan-Meier analyses using TCGA-BRAC data. The phenotype changes of NK cells in ER+/HER2-BC after overexpressing S100A9 in cancer cells were evaluated by the production levels of IFN-gamma, perforin and granzyme B and cytotoxicity assay.

RESULTS

By analyzing scRNA-seq data, we found that multiple genes involved in cellular stress response were upregulated in ER+/HER2-BC compared with TNBC. Moreover, TLR regulation pathway was significantly enriched using differentially expressed genes (DEGs) from comparing the transcriptome data of ER+/HER2-BC and TNBC cancer cells, and NK cell infiltration high/low groups. Among the DEGs, S100A9 was identified as a key regulator. Patients with higher expression levels of S100A9 and NK cell activation markers had better overall survival. Furthermore, we proved that overexpression of S100A9 in ER+/HER2-cells could improve cocultured NK cell function.

CONCLUSION

In conclusion, the study we presented demonstrated that NK cells in ER+/HER2-BC were hypofunctional, and S100A9 was an important regulator of NK cell function in ER+BC. Our work contributes to elucidate the regulatory networks between cancer cells and NK cells and may provide theoretical basis for novel drug development.

Understanding the Mode of Action of a Micro-Immunotherapy Formulation: Pre-Clinical Evidence from the Study of 2LEBV® Active Ingredients

BACKGROUND

Epstein-Barr virus (EBV) is often kept silent and asymptomatic; however, its reactivation induces a chronic and/or recurrent infection that is associated with numerous diseases, including cancer and inflammation-related disorders. As no specific treatment is currently available, the immune factors-based micro-immunotherapy (MI) medicine 2LEBV® could be considered a valuable therapeutic option to sustain the immune system in EBV reactivation.

METHODS

The present work aimed to investigate, for the first time, the effect of 2LEBV® in several in vitro models of uninfected immune-related cells.

RESULTS

2LEBV® displayed phagocytosis-enhancing capabilities in granulocytes. In human peripheral blood mononuclear cells (PBMCs), it increased the intra- and extra-cellular expression of interleukin (IL)-2. Moreover, it modulated the secretion of other cytokines, increasing IL-4, IL-6, and tumor necrosis factor-α levels or lowering other cytokines levels such as IL-9. Finally, 2LEBV® reduced the expression of human leukocyte antigen (HLA)-II in endothelial cells and macrophages.

CONCLUSIONS

Although these data are still preliminary and the chosen models do not consider the underlying EBV-reactivation mechanisms, they still provide a better understanding of the mechanisms of action of 2LEBV®, both at functional and molecular levels. Furthermore, they open perspectives regarding the potential targets of 2LEBV® in its employment as a therapeutic intervention for EBV-associated diseases.

Immune checkpoint targeting antibodies hold promise for combinatorial cancer therapeutics

Through improving the immune system's ability to recognize and combat tumor cells as well as its receptivity to changes in the tumor microenvironment, immunotherapy has emerged as a highly successful addition to the treatment of cancer. However, tumor heterogeneity poses a significant challenge in cancer therapy as it can undermine the anti-tumor immune response through the manipulation of the extracellular matrix. To address these challenges and improve targeted therapies and combination treatments, the food and drug administration has approved several immunomodulatory antibodies to suppress immunological checkpoints. Combinatorial therapies necessitate the identification of multiple targets that regulate the intricate communication between immune cells, cytokines, chemokines, and cellular responses within the tumor microenvironment. The purpose of this study is to provide a comprehensive overview of the ongoing clinical trials involving immunomodulatory antibodies in various cancer types. It explores the potential of these antibodies to modulate the immune system and enhance anti-tumor responses. Additionally, it discusses the perspectives and prospects of immunomodulatory therapeutics in cancer treatment. Although immunotherapy shows great promise in cancer treatment, it is not exempt from side effects that can arise due to hyperactivity of the immune system. Therefore, understanding the intricate balance between immune activation and regulation is crucial for minimizing these adverse effects and optimizing treatment outcomes. This study aims to contribute to the growing body of knowledge surrounding immunomodulatory antibodies and their potential as effective therapeutic options in cancer treatment, ultimately paving the way for improved patient outcomes and deepening our perception of the intricate interactivity between the immune system and tumors.

Immune microenvironment of cervical cancer and the role of IL-2 in tumor promotion

The tumor microenvironment (TME) is a heterogeneous mixture of resident and tumor cells that maintain close communication through their secretion products. The composition of the TME is dynamic and complex among the different types of cancer, where the immune cells play a relevant role in the elimination of tumor cells, however, under certain circumstances they contribute to tumor development. In cervical cancer (CC) the human papilloma virus (HPV) shapes the microenvironment in order to mediate persistent infections that favors transformation and tumor development. Interleukin-2 (IL-2) is an important TME cytokine that induces CD8+ effector T cells and NKs to eliminate tumor cells, however, IL-2 can also suppress the immune response through Treg cells. Recent studies have shown that CC cells express the IL-2 receptor (IL-2R), that are induced to proliferate at low concentrations of exogenous IL-2 through alterations in the JAK/STAT pathway. This review provides an overview of the main immune cells that make up the TME in CC, as well as the participation of IL-2 in the tumor promotion. Finally, it is proposed that the low density of IL-2 produced by immunocompetent cells is used by tumor cells through its IL-2R as a mechanism to proliferate simultaneously depleting this molecule in order to evade immune response.

Ex vivo expansion of natural killer cells for hematological cancer immunotherapy: a systematic review and meta-analysis

The present systematic review aimed to investigate natural killer (NK) cell ex vivo expansion protocols within the scope of clinical trials targeting hematological cancer and to conduct a meta-analysis to assess the effect of NK cell infusion on survival. Research articles of clinical studies in which cell products produced by ex vivo expansion, consisting of a certain amount of NK cells and infused to patients with hematological cancer, were included in the systematic review. We conducted a proportion analysis with random effects for product purity and viability values. Studies having control groups were included in the survival meta-analysis. Among 11.028 identified records, 21 were included in the systematic review. We observed statistically significant heterogeneity for viability (I2 = 97.83%, p < 0.001) and purity values (I2 = 99.95%, p < 0.001), which was attributed to the diversity among isolation and expansion protocols. In addition, the survival meta-analysis findings suggested that NK cell therapy favors disease-free survival (DFS) of patients with myeloid malignancies but limited to only two clinical studies (odds ratio = 3.40 (confidence interval:1.27-9.10), p = 0.01). While included protocols yielded cell products with acceptable viability, the utility of immunomagnetic methods; feeder cells such as K562 expressing membrane-bound IL15 and 4-1BBL or expressing membrane-bound IL21 and 4-1BBL might be preferable to achieve better purity. In conclusion, NK cell therapy has a potential to improve DFS of patients with myeloid malignancies.

DHEA Induces Sex-Associated Differential Patterns in Cytokine and Antibody Levels in Mice Infected with Plasmodium berghei ANKA

Malaria is the most lethal parasitic disease worldwide; the severity of symptoms and mortality are higher in men than in women, exhibiting an evident sexual dimorphism in the immune response; therefore, the contribution of 17β-estradiol and testosterone to this phenomenon has been studied. Both hormones differentially affect several aspects of innate and adaptive immunity. Dehydroepiandrosterone (DHEA) is the precursor of both hormones and is the sexual steroid in higher concentrations in humans, with immunomodulatory properties in different parasitic diseases; however, the involvement of DHEA in this sexual dimorphism has not been studied. In the case of malaria, the only information is that higher levels of DHEA are associated with reduced Plasmodium falciparum parasitemia. Therefore, this work aims to analyze the DHEA contribution to the sexual dimorphism of the immune response in malaria. We assessed the effect of modifying the concentration of DHEA on parasitemia, the number of immune cells in the spleen, cytokines, and antibody levels in plasma of CBA/Ca mice infected with Plasmodium berghei ANKA (P. berghei ANKA). DHEA differentially affected the immune response in males and females: it decreased IFN-γ, IL-2 and IL-4 concentrations only in females, whereas in gonadectomized males, it increased IgG2a and IgG3 antibodies. The results presented here show that DHEA modulates the immune response against Plasmodium differently in each sex, which helps to explain the sexual dimorphism present in malaria.

Engineered E. coli Nissle 1917 for delivery of bioactive IL-2 for cancer immunotherapy

In this study we performed a step-wise optimization of biologically active IL-2 for delivery using E. coli Nissle 1917. Engineering of the strain was coupled with an in vitro cell assay to measure the biological activity of microbially produced IL-2 (mi-IL2). Next, we assessed the immune modulatory potential of mi-IL2 using a 3D tumor spheroid model demonstrating a strong effect on immune cell activation. Finally, we evaluated the anticancer properties of the engineered strain in a murine CT26 tumor model. The engineered strain was injected intravenously and selectively colonized tumors. The treatment was well-tolerated, and tumors of treated mice showed a modest reduction in tumor growth rate, as well as significantly elevated levels of IL-2 in the tumor. This work demonstrates a workflow for researchers interested in engineering E. coli Nissle for a new class of microbial therapy against cancer.

Recombinant Human Interleukin-2 Corrects NK Cell Phenotype and Functional Activity in Patients with Post-COVID Syndrome

Post-COVID syndrome develops in 10–20% of people who have recovered from COVID-19 and it is characterized by impaired function of the nervous, cardiovascular, and immune systems. Previously, it was found that patients who recovered from infection with the SARS-CoV-2 virus had a decrease in the number and functional activity of NK cells. The aim of the study was to assess the effectiveness of recombinant human IL-2 (rhIL-2) administered to correct NK cell phenotype and functional activity in patients with post-COVID syndrome. Patients were examined after 3 months for acute COVID-19 of varying severity. The phenotype of the peripheral blood NK cells was studied by flow cytometry. It was found that disturbances in the cell subset composition in patients with post-COVID syndrome were characterized by low levels of mature (p = 0.001) and cytotoxic NK cells (p = 0.013), with increased release of immature NK cells (p = 0.023). Functional deficiency of NK cells in post-COVID syndrome was characterized by lowered cytotoxic activity due to the decreased count of CD57+ (p = 0.001) and CD8+ (p < 0.001) NK cells. In the treatment of patients with post-COVID syndrome with recombinant IL-2, peripheral blood NK cell count and functional potential were restored. In general, the effectiveness of using rhIL-2 in treatment of post-COVID syndrome has been proven in patients with low levels of NK cells.

Prevention and control of chicken coccidiosis construction of recombinant Lactococcus lactis expressing chicken IL-4 and IL-2 fusion protein and its immune synergistic effect on chicken coccidia live vaccine

Intestinal mucosa injury and loss of weight gain are unavoidable while using live vaccine strain to prevent chicken coccidiosis. In this study, recombinant Lactococcus lactis NZ3900/pNZ8149-IL-4-IL-2, expressing the fusion protein of chicken IL-4 and IL-2, was constructed using food-grade NICE expression system, trying to develop a possible oral immune adjuvant to enhance the immune effect of the live vaccine against chicken coccidiosis and minimize its adverse effects. Chickens were given different doses of recombinant L. lactis together with the live vaccine, then experimently attacked with coccidia virulent strains. Results showed that weight gains of co-immunization groups, given both 1 × 10⁹ or 1 × 10¹⁰ CFU recombinant L. lactis and the live vaccine, were significantly higher than the vaccine-only group (P<0.05), while intestinal lesion scores of duodenum, jejunum, and cecum were significantly lower than the vaccine-only group (P<0.05), so was the oocyst shedding. The anticoccidial indexes (ACI) of the co-immunized groups given 1 × 10⁹ and 1 × 10¹⁰ CFU recombinant L. lactis were 187.85 and 193.33, respectively, higher than 174.61 of the vaccine-only group. In addition, chickens in co-immunization groups gained more body weight than the vaccine-only group before being challenged with the virulent strains (P<0.05). All the results indicated that the constructed recombinant L. lactis NZ3900/ pNZ8149-IL-4-IL-2 exhibited an immune synergistic function to coccidiosis live vaccine, and could alleviate its adverse effect affecting weight gain. The application of the recombinant L. lactis showed the potency to lift the anticoccidial efficiency of the live vaccine from a medium level to a high level.

The Promises of Natural Killer Cell Therapy in Endometriosis

Endometriosis is a gynaecological disease defined by the growth of endometrium-like tissue outside the uterus. The disease is present in approximately 5–10% of women of reproductive age and causes pelvic pain and infertility. The pathophysiology is not completely understood, but retrograde menstruation and deficiency in natural killer (NK) cells that clear endometriotic cells in the peritoneal cavity play an important role. Nowadays, hormonal therapy and surgery to remove endometriosis lesions are used as treatment. However, these therapies do not work for all patients, and hormonal therapy prevents patients from getting pregnant. Therefore, new treatment strategies should be developed. Since the cytotoxicity of NK cells is decreased in endometriosis, we performed a literature search into the possibility of NK cell therapy. Available treatment options include the inhibition of receptor–ligand interaction for KIR2DL1, NKG2A, LILRB1/2, and PD-1/PD-L1; inhibition of TGF-β; stimulation of NK cells with IL-2; and mycobacterial treatment with BCG. In preclinical work, these therapies show promising results but unfortunately have side effects, which have not specifically been studied in endometriosis patients. Before NK cell treatment can be used in the clinic, more research is needed.

Reprogramming the tumor microenvironment by genome editing for precision cancer therapy

The tumor microenvironment (TME) is essential for immune escape by tumor cells. It plays essential roles in tumor development and metastasis. The clinical outcomes of tumors are often closely related to individual differences in the patient TME. Therefore, reprogramming TME cells and their intercellular communication is an attractive and promising strategy for cancer therapy. TME cells consist of immune and nonimmune cells. These cells need to be manipulated precisely and safely to improve cancer therapy. Furthermore, it is encouraging that this field has rapidly developed in recent years with the advent and development of gene editing technologies. In this review, we briefly introduce gene editing technologies and systematically summarize their applications in the TME for precision cancer therapy, including the reprogramming of TME cells and their intercellular communication. TME cell reprogramming can regulate cell differentiation, proliferation, and function. Moreover, reprogramming the intercellular communication of TME cells can optimize immune infiltration and the specific recognition of tumor cells by immune cells. Thus, gene editing will pave the way for further breakthroughs in precision cancer therapy.

Mathematical Modeling of Proliferative Immune Response Initiated by Interactions Between Classical Antigen-Presenting Cells Under Joint Antagonistic IL-2 and IL-4 Signaling

During an adaptive immune response from pathogen invasion, multiple cytokines are produced by various immune cells interacting jointly at the cellular level to mediate several processes. For example, studies have shown that regulation of interleukin-4 (IL-4) correlates with interleukin-2 (IL-2) induced lymphocyte proliferation. This motivates the need to better understand and model the mechanisms driving the dynamic interplay of proliferation of lymphocytes with the complex interaction effects of cytokines during an immune response. To address this challenge, we adopt a hybrid computational approach comprising of continuous, discrete and stochastic non-linear model formulations to predict a system-level immune response as a function of multiple dependent signals and interacting agents including cytokines and targeted immune cells. We propose a hybrid ordinary differential equation-based (ODE) multicellular model system with a stochastic component of antigen microscopic states denoted as Multiscale Multicellular Quantitative Evaluator (MMQE) implemented using MATLAB. MMQE combines well-defined immune response network-based rules and ODE models to capture the complex dynamic interactions between the proliferation levels of different types of communicating lymphocyte agents mediated by joint regulation of IL-2 and IL-4 to predict the emergent global behavior of the system during an immune response. We model the activation of the immune system in terms of different activation protocols of helper T cells by the interplay of independent biological agents of classic antigen-presenting cells (APCs) and their joint activation which is confounded by the exposure time to external pathogens. MMQE quantifies the dynamics of lymphocyte proliferation during pathogen invasion as bivariate distributions of IL-2 and IL-4 concentration levels. Specifically, by varying activation agents such as dendritic cells (DC), B cells and their joint mechanism of activation, we quantify how lymphocyte activation and differentiation protocols boost the immune response against pathogen invasion mediated by a joint downregulation of IL-4 and upregulation of IL-2. We further compare our in-silico results to in-vivo and in-vitro experimental studies for validation. In general, MMQE combines intracellular and extracellular effects from multiple interacting systems into simpler dynamic behaviors for better interpretability. It can be used to aid engineering of anti-infection drugs or optimizing drug combination therapies against several diseases.

Natural killer cell-targeted immunotherapy for cancer

Natural killer (NK) cells were initially described in the early 1970s as major histocompatibility complex unrestricted killers due to their ability to spontaneously kill certain tumor cells. In the past decade, the field of NK cell-based treatment has been accelerating exponentially, holding a dominant position in cancer immunotherapy innovation. Generally, research on NK cell-mediated antitumor therapies can be categorized into three areas: choosing the optimal source of allogenic NK cells to yield massively amplified "off-the-shelf" products, improving NK cell cytotoxicity and longevity, and engineering NK cells with the ability of tumor-specific recognition. In this review, we focused on NK cell manufacturing techniques, some auxiliary methods to enhance the therapeutic efficacy of NK cells, chimeric antigen receptor NK cells, and monoclonal antibodies targeting inhibitory receptors, which can significantly augment the antitumor activity of NK cells. Notably, emerging evidence suggests that NK cells are a promising constituent of multipronged therapeutic strategies, strengthening immune responses to cancer.

IL-2/JES6-1 mAb complexes dramatically increase sensitivity to LPS through IFN-γ production by CD25+Foxp3- T cells

Complexes of IL-2 and JES6-1 mAb (IL-2/JES6) provide strong sustained IL-2 signal selective for CD25⁺ cells and thus they potently expand T_reg cells. IL-2/JES6 are effective in the treatment of autoimmune diseases and in protecting against rejection of pancreatic islet allografts. However, we found that IL-2/JES6 also dramatically increase sensitivity to LPS-mediated shock in C57BL/6 mice. We demonstrate here that this phenomenon is dependent on endogenous IFN-γ and T cells, as it is not manifested in IFN-γ deficient and nude mice, respectively. Administration of IL-2/JES6 leads to the emergence of CD25⁺Foxp3^-CD4⁺ and CD25⁺Foxp3^-CD8⁺ T cells producing IFN-γ in various organs, particularly in the liver. IL-2/JES6 also increase counts of CD11b⁺CD14⁺ cells in the blood and the spleen with higher sensitivity to LPS in terms of TNF-α production and induce expression of CD25 in these cells. These findings indicate safety issue for potential use of IL-2/JES6 or similar IL-2-like immunotherapeutics.

Increased Levels of CD107a and Intracellular Cytokines in IL-2 Stimulated PBMCs from Endometriosis Patients

It has been postulated that the immune system is impaired in individuals with endometriosis, with attention directed to natural killer (NK) cells. Specifically, it has been hypothesized that altered numbers of peripheral NK cells in blood are associated with the presence of endometriotic lesions. This study aimed to evaluate the level of the peripheral NK cell surface marker CD107a in endometriosis in the presence of IL-2 stimulation. Peripheral blood mononuclear cells (PBMCs) were obtained from 7 women with endometriosis and 7 women without endometriosis. The PBMCs were divided into two groups and either treated with recombinant IL-2 or left untreated. The cytotoxic activity of the PBMCs toward target cells (K562) was evaluated. Then, both groups were cocultured for 4 days. The expressions of CD107a, TNF-α, and IFN-γ were determined using flow cytometry analysis. There was no difference in the expression of CD107a prior to IL-2 stimulation in PBMCs from women with endometriosis compared to those from women without endometriosis. However, we observed upregulation of the expression of the surface marker CD107a after treatment in the endometriosis group. In addition, there was a significant difference in CD107a expression in the endometriosis group before versus after stimulation with IL-2 (p < 0.01). We also found no difference in the production of TNF-α and IFN-γ before versus after treatment with IL-2 in either groups. The levels of CD107a were significantly enhanced in peripheral blood taken from women with endometriosis after treatment with IL-2.

Novel Discoveries in Immune Dysregulation in Inborn Errors of Immunity

With the expansion of our knowledge on inborn errors of immunity (IEI), it gradually becomes clear that immune dysregulation plays an important part. In some cases, autoimmunity, hyperinflammation and lymphoproliferation are far more serious than infections. Thus, immune dysregulation has become significant in disease monitoring and treatment. In recent years, the wide application of whole-exome sequencing/whole-genome sequencing has tremendously promoted the discovery and further studies of new IEI. The number of discovered IEI is growing rapidly, followed by numerous studies of their pathogenesis and therapy. In this review, we focus on novel discovered primary immune dysregulation diseases, including deficiency of SLC7A7, CD122, DEF6, FERMT1, TGFB1, RIPK1, CD137, TET2 and SOCS1. We discuss their genetic mutation, symptoms and current therapeutic methods, and point out the gaps in this field.

Implications of a 'Third Signal' in NK Cells

Innate and adaptive immune systems are evolutionarily divergent. Primary signaling in T and B cells depends on somatically rearranged clonotypic receptors. In contrast, NK cells use germline-encoded non-clonotypic receptors such as NCRs, NKG2D, and Ly49H. Proliferation and effector functions of T and B cells are dictated by unique peptide epitopes presented on MHC or soluble humoral antigens. However, in NK cells, the primary signals are mediated by self or viral proteins. Secondary signaling mediated by various cytokines is involved in metabolic reprogramming, proliferation, terminal maturation, or memory formation in both innate and adaptive lymphocytes. The family of common gamma (γc) cytokine receptors, including IL-2Rα/β/γ, IL-7Rα/γ, IL-15Rα/β/γ, and IL-21Rα/γ are the prime examples of these secondary signals. A distinct set of cytokine receptors mediate a ‘third’ set of signaling. These include IL-12Rβ1/β2, IL-18Rα/β, IL-23R, IL-27R (WSX-1/gp130), IL-35R (IL-12Rβ2/gp130), and IL-39R (IL-23Rα/gp130) that can prime, activate, and mediate effector functions in lymphocytes. The existence of the ‘third’ signal is known in both innate and adaptive lymphocytes. However, the necessity, context, and functional relevance of this ‘third signal’ in NK cells are elusive. Here, we define the current paradigm of the ‘third’ signal in NK cells and enumerate its clinical implications.

AML and the art of remission maintenance

Relapse in acute myeloid leukemia (AML) is common, especially in older patients, and there is currently no standard of care maintenance therapy for those who achieve complete remission. Finding effective, tolerable maintenance therapy to prolong remission has been a goal for decades, but early clinical trials testing a variety of agents demonstrated disappointing results with no overall survival benefit. CC-486, an oral hypomethylating agent, was recently approved in the United States for maintenance treatment in patients with AML in first remission following chemotherapy. A number of ongoing studies are assessing various therapeutics in the maintenance setting, including other hypomethylating agents, targeted small-molecule inhibitors, monoclonal antibodies, and immunomodulators. New strategies are needed to identify patients most likely to benefit from maintenance therapy, including those for whom a preemptive approach reliant on monitoring of measurable residual disease would be advantageous.

Paving the Way Towards Universal Chimeric Antigen Receptor Therapy in Cancer Treatment: Current Landscape and Progress

Chimeric antigen receptor (CAR) therapy has been proved effective in a stream of clinical trials, especially in hematologic malignancies. However, current CAR therapy is highly personalized as cells used are derived from patients themselves, which can be costly, time-consuming, and sometimes fails to achieve optimal therapeutic results due to poor quality/quantity of patient-derived cells. On the contrary, universal CAR therapy, which is based on healthy individuals’ cells, circumvents several limitations of current autologous CAR therapy. To achieve the universality of CAR therapy, the allogeneic cell transplantation related issues, such as graft-versus-host disease (GVHD) and host-versus-graft activities (HVGA), must be addressed. In this review, we focus on current progress regarding GVHD and HVGA in the universal CAR therapy, followed by a universal CAR design that may be applied to allogeneic cells and a summary of key clinical trials in this field. This review may provide valuable insights into the future design of universal CAR products.

Notch1 is crucial for decidualization and maintaining the first pregnancy in the mouse†

The endometrium undergoes a pregnancy-delivery-repair cycle multiple times during the reproductive lifespan in females. Decidualization is one of the critical events for the success of this essential process. We have previously reported that Notch1 is essential for artificial decidualization in mice. However, in a natural pregnancy, the deletion of Notch1 (PgrCre/+Notch1f/f, or Notch1d/d) only affects female fertility in the first 30 days of a 6-month fertility test, but not the later stages. In the present study, we undertook a closer evaluation at the first pregnancy of these mice to attempt to understand this puzzling phenomenon. We observed a large number of pregnancy losses in Notch1d/d mice in their first pregnancy, which led to the subfertility observed in the first 30 days of the fertility test. We then demonstrated that the initial pregnancy loss is a consequence of impaired decidualization. Furthermore, we identified a group of genes that contribute to Notch1 regulated decidualization in a natural pregnancy. Gene ontogeny analysis showed that these differentially expressed genes in the natural pregnancy are involved in cell-cell and cell-matrix interactions, different from genes that have been previously identified from the artificial decidualization model, which contribute to cell proliferation and apoptosis. In summary, we determined that Notch1 is essential for normal decidualization in the mouse uterus only in the first pregnancy but not in subsequent ones.

[Immunotherapy of metastatic non-small cell lung cancer from first line to resistance and its management]

Immunotherapy alone or in combination with chemotherapy is now an integral part of the treatment of metastatic NSCLC. This treatment is transforming the management of these cancers, with 20-30% of patients achieving long survival. However, disease progression under treatment is still the rule for the majority of patients, raising problems both in understanding its mechanisms and in subsequent appropriate management. This study examines current therapeutic options and proposes solutions to circumvent resistance to immunotherapy. The mechanisms of resistance to these treatments is also analysed.

Lack of cell movement impairs survival of peripheral blood IL-2-stimulated natural killer cells originating from solid cancer and promotes red blood cells to induce their switch toward a regulatory phenotype

BACKGROUND

Red blood cells (RBCs) can have a modulatory effect on immune cells; so changes in their dynamism could considerably influence their physiology, and consequently the immune activities of neighbouring cells, like natural killer (NK) cells. Herein, we studied the effect of both RBCs and lack of cell movement on the proliferation, survival and regulation of peripheral IL-2-stimulated NK cells from normal and solid malignant conditions.

METHODS

Experiments were conducted on twelve cell culture groups, including NK cells from patients with solid malignant tumor or healthy controls, cultured alone or with autologous or nonautologous RBCs under shaking or no shaking conditions.

RESULTS

NK cells from neoplastic patients behaved differently depending on the culture conditions including shaking and/or RBCs presence. Therefore, NK cells survival was downregulated in the absence of shaking; whereas, shaking have not only upregulated cell survival, but also downregulated the levels of p53-related apoptosis. Moreover, RBCs enhanced NK cells proliferation; while, this effect was modulated by shaking. Furthermore, RBCs can generate opposite effects on the production and modulation of protumoral or immunosuppressive cytokines, depending on the origin of NK cells, i.e., whether they derive from healthy or solid malignant tumor conditions. Finally, NK cells become able to express Foxp3 regulatory marker when combining three main conditions that include (i) treatment with high dose of IL-2, (ii) presence of RBCs, and (iii) absence of shaking.

CONCLUSIONS

Our outcomes showed for the first time that cell stagnation would be markedly involved in peripheral NK cell apoptosis, as well as in switching toward a regulatory phenotype-induced Foxp3. Cell movement may be one of ex vivo potential approaches in boosting the activities and survival of such cells during solid cancer.

Adult peripheral blood and umbilical cord blood NK cells are good sources for effective CAR therapy against CD19 positive leukemic cells

Among hematological cancers, Acute Lymphoblastic Leukemia (ALL) and Chronic Lymphocytic Leukemia (CLL) are the most common leukemia in children and elderly people respectively. Some patients do not respond to chemotherapy treatments and it is necessary to complement it with immunotherapy-based treatments such as chimeric antigen receptor (CAR) therapy, which is one of the newest and more effective treatments against these cancers and B-cell lymphoma. Although complete remission results are promising, CAR T cell therapy presents still some risks for the patients, including cytokine release syndrome (CRS) and neurotoxicity. We proposed a different immune cell source for CAR therapy that might prevent these side effects while efficiently targeting malignant cells. NK cells from different sources are a promising vehicle for CAR therapy, as they do not cause graft versus host disease (GvHD) in allogenic therapies and they are prompt to attack cancer cells without prior sensitization. We studied the efficacy of NK cells from adult peripheral blood (AB) and umbilical cord blood (CB) against different target cells in order to determine the best source for CAR therapy. AB CAR-NK cells are slightly better at killing CD19 presenting target cells and CB NK cells are easier to stimulate and they have more stable number from donor to donor. We conclude that CAR-NK cells from both sources have their advantages to be an alternative and safer candidate for CAR therapy.

Membrane bound IL-21 based NK cell feeder cells drive robust expansion and metabolic activation of NK cells

NK cell adoptive therapy is a promising cancer therapeutic approach, but there are significant challenges that limiting its feasibility and clinical efficacy. One difficulty is the paucity of clinical grade manufacturing platforms to support the large scale expansion of highly active NK cells. We created an NK cell feeder cell line termed 'NKF' through overexpressing membrane bound IL-21 that is capable of inducing robust and sustained proliferation (>10,000-fold expansion at 5 weeks) of highly cytotoxic NK cells. The expanded NK cells exhibit increased cytotoxic function against a panel of blood cancer and solid tumor cells as compared to IL-2-activated non-expanded NK cells. The NKF-expanded NK cells also demonstrate efficacy in mouse models of human sarcoma and T cell leukemia. Mechanistic studies revealed that membrane-bound IL-21 leads to an activation of a STAT3/c-Myc pathway and increased NK cell metabolism with a shift towards aerobic glycolysis. The NKF feeder cell line is a promising new platform that enables the large scale proliferation of highly active NK cells in support of large scale third party NK cell clinical studies that have been recently intiatied. These results also provide mechanistic insights into how membrane-bound IL-21 regulates NK cell expansion.

Schistosoma japonicum Infection Promotes the Response of Tfh Cells Through Down-Regulation of Caspase-3-Mediating Apoptosis

CD4⁺ T follicular helper (Tfh) cells, a new subset of immune cells, have been demonstrated to be involved in granulomatous responses to Schistosoma japonicum (S. japonicum) infection. However, the role and underlying mechanisms of Tfh cell aggregation in S. japonicum infection remain incompletely understood. In this study, we provide evidence that S. japonicum infection enhances the accumulation of Tfh cells in the spleen, lymph nodes, and peripheral blood of C57BL/6 mice. Infection-induced Tfh cells exhibited more potent effects directly on B cell responses than the control Tfh cells (P < 0.05). Furthermore, reduced apoptosis of Tfh cells was found both in S. japonicum infected mice and in soluble egg antigen (SEA) treated Tfh cells (P < 0.05). Mechanistic studies reveal that caspase-3 is the primary drivers of down-regulated apoptotic Tfh cell death in S. japonicum infection. In summary, this study demonstrates that Tfh cell accumulation might have an impact on the generation of immune responses in S. japonicum infection, and caspase-3 signaling mediated apoptosis down-regulation might responsible for the accumulation of Tfh cell in this course.

Propofol Promotes Activity and Tumor-Killing Ability of Natural Killer Cells in Peripheral Blood of Patients with Colon Cancer

Background

We investigated the effect of propofol on activities and tumor-killing ability of natural killer (NK) cells in patients with colon cancer.

Material/Methods

Twenty colon cancer patients and 20 healthy subjects were included. Peripheral blood (5 ml) was collected from all patients and healthy subjects. NK cells in peripheral blood were separated by negative screening using immunomagnetic beads. Flow cytometry was used to determine expression of activated receptors, inhibitory receptors, killing effector molecules, and proliferation-associated markers on NK cell surfaces. After in vitro treatment with propofol for 24 h, expression of activated receptors, inhibitory receptors, killing effector molecules, and proliferation-associated markers on NK cell surfaces was examined again. In addition, the tumor-killing effect of NK cells was studied by co-culture with K562 cells or colon cancer SW620 cells at a ratio of 1: 1.

Results

The number of NK cells in peripheral blood from colon cancer patients was increased compared with healthy subjects, but activities and proliferation ability of the NK cells were decreased. The tumor-killing effect of NK cells isolated from colon cancer patients was decreased. Of note, propofol promoted activation of NK cells from colon cancer patients. In addition, propofol increased expression of tumor-killing effector molecules by NK cells and the proliferation ability of NK cells. Propofol also enhanced the killing effect of NK cells on colon cancer cells.

Conclusions

The present study demonstrates that propofol promotes the activity and tumor-killing ability of NK cells in peripheral blood of patients with colon cancer.