Combination Of IL-2 Research Articles

Combined IL-12, IL-15 and IL-18 activation induces epigenetic changes in human NK cells during the memory-like state transition

Abstract NK cells exhibit memory properties after activation with haptens, viral infection, or cytokines with each stimulus having distinct biology. Memory-like (ML) NK cells differentiate over one week after brief activation with combined IL-12/15/18, and have augmented responses upon restimulation by cytokines, activating receptor, or tumor targets. While much is known about their functional characteristics, there are large gaps in our understanding of the molecular mechanisms involved in programming conventional (c)NK cells into ML NK cells. As ML NK cells have enhanced ability to produce IFN-γ after multiple cell divisions, this suggests that the IFNG gene, and others, may be epigenetically poised. Therefore, we hypothesize that activation with IL-12/15/18 triggers epigenetic remodeling of cNK cells to ML NK cells that drives enhanced functionality. To test this, we performed ATAC-seq on baseline cNK cells, IL-12/15/18 activated NK cells, and in vitro differentiated cNK and ML NK cells after one week. Activation with IL-12/15/18 induces dramatic early epigenetic remodeling with >10,000 differentially accessible regions (DARs) compared to cNK cells. Moreover, ML differentiation generates epigenetically distinct ML NK cells (>1,000 DARs) compared to in vitro differentiated cNK cells, including increased IFNG locus accessibility, suggesting epigenetic mechanisms regulate their enhanced functionality. Also, ML NK cells are markedly different from IL-12/15/18 activated NK cells (>15,000 DARs) suggesting not all epigenetic changes are immediately induced, and time is required for full implementation of the memory-like state. Together, this supports that ML NK cells rely on epigenetic programming for enhanced function. Supported by grants from NIH (P50CA171963, R01CA205239, P30CA91842, 1F31GM146361-01).

Immunotherapy with IL12 and PD1/CTLA4 inhibition is effective in advanced ovarian cancer and associates with reversal of myeloid cell-induced immunosuppression

ABSTRACT The tumor microenvironment (TME) in ovarian cancer (OC) is characterized by immune suppression, due to an abundance of suppressive immune cells populations. To effectively enhance the activity of immune checkpoint inhibition (ICI), there is a need to identify agents that target these immunosuppressive networks while promoting the recruitment of effector T cells into the TME. To this end, we sought to investigate the effect of the immunomodulatory cytokine IL12 alone or in combination with dual-ICI (anti-PD1 + anti-CTLA4) on anti-tumor activity and survival, using the immunocompetent ID8-VEGF murine OC model. Detailed immunophenotyping of peripheral blood, ascites, and tumors revealed that durable treatment responses were associated with reversal of myeloid cell-induced immune suppression, which resulted in enhanced anti-tumor activity by T cells. Single cell transcriptomic analysis further demonstrated striking differences in the phenotype of myeloid cells from mice treated with IL12 in combination with dual-ICI. We also identified marked differences in treated mice that were in remission compared to those whose tumors progressed, further confirming a pivotal role for the modulation of myeloid cell function to allow for response to immunotherapy. These findings provide the scientific basis for the combination of IL12 and ICI to improve clinical response in OC.

Abstract 3197: Adoptive T cell therapy using IL-7 and IL-15 expanded HER2-specific CD4 T cells for metastatic breast cancer

Abstract BACKGROUND: Adoptive cell therapy (ACT) has had limited success due to low T cell infiltration in breast cancer (BC) patients. We have shown that administration of class II HER2 peptide pulsed type I polarized dendritic cell (DC1) vaccines leads to increase in CD4 T cells in the periphery of BC patients. In this study, we investigated the feasibility of expanding CD4 T cells from peripheral blood mononuclear cells (PBMC) of HER2-DC1 vaccinated BC patients. METHODS: PBMCs from BC patients receiving HER2-DC1 vaccines were used for CD4 T cell expansion. PBMCs were co-cultured with HER2-DC1 at 10:1 ratio for initial activation followed by expansion with cytokines- IL-2 and IL-7 or IL-15. Expanded T cells were assessed for immune marker phenotyping by flow cytometry and TCRvb analysis. For TCRvB analysis, pre, post DC1, IL-7 and IL-15 expanded CD4 T cells were pelleted for DNA isolation and sequenced using Immunoseq Analyzer platform. In addition, we investigated the in vivo efficacy of adoptively transferred mouse IL-7/IL-15 expanded Her2 specific CD4 T cells in HER2+ TUBO mouse model. RESULTS: Co-culturing of patient PBMCs with HER2-DC1 in the presence of cytokines IL-2, IL-7 and IL-15 expanded CD4 T cells ranging from 8-43 fold expansion in different samples with 92-98% CD4 phenotype. CD4 T cells expanded in IL-7 had stem like memory phenotype while IL-15 skewed to terminally differentiated CD4 T cells. IL-7 expanded T cells had significantly higher Tim3 and Ox40 expression, and effector memory proportion as compared to the IL-15 expanded T cells. Restimulation of expanded T cells with HER2 pulsed DCs showed HER2 specificity as measured by increased interferon-gamma production We identified top five clones in PBMCs from DC1-HER2 vaccinated BC patients compared to baseline. We observed differential abundance of TCR clones under IL-7 and IL-15 conditions and identified unique clones for IL-7 and IL-15. ACT using a combination of IL-7 and IL-15 expanded mouse CD4 T cells led to 50% tumor regression in HER2+ model. CONCLUSION: These studies demonstrate that HER2 specific CD4 T cells can be successfully expanded from HER2-DC1 vaccinated patients. Post HER2 DC1 vaccine can generate a pool of antigen specific CD4 T cells and may offer a promising ACT for HER2 BC. Further studies are warranted to demonstrate the efficacy in the clinical setting. Citation Format: Namrata Gautam, Krithika Kodumudi, Colin Snyder, Amber Beyer, Ricardo Costa, Heather Han, Brian Czerniecki. Adoptive T cell therapy using IL-7 and IL-15 expanded HER2-specific CD4 T cells for metastatic breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3197.

Treg-targeted efficient-inducible platform for collagen-induced arthritis treatment.

Regulatory T cells (Tregs) display great promise in rheumatoid arthritis (RA) therapy. However, their low number and differentiation rate limit their further application in the clinics. In the present study, we first optimized a combination of IL-2, TGF-β and cyclin dependent kinase inhibitor AS2863619 (IL-2/TGF-β/AS), which could induce Tregs with high efficiency in vitro. After the induced Tregs (iTregs) were confirmed to suppress lymphocyte proliferation and pro-inflammatory T help cells (Th1 and Th17) activation, a chitosan-stabilized nanoparticle drug delivery system (NDDS) was developed according to the optimized formula of IL-2/TGF-β/AS. In vivo study, the NDDS was injected into the knees of mice with collagen-induced arthritis (CIA). As a result, the NDDS remarkably reduced the pathological score of the CIA, alleviated the inflammatory cell infiltration and synovial hyperplasia, and minimized cartilage tissue damage in the knee joint of the CIA mice. Mechanically, the NDDS administration promoted Treg differentiation and decreased Th17 production, consequently reversing the ratio of Treg/Th17, and reducing the secretion of TNF-α in the sera, which facilitated to relieve the severity and progression of arthritis. In sum, NDDS capable of efficiently inducing Tregs were constructed successfully and provided a potential platform for treating RA by restoring the equilibrium of Treg/Th17 destroyed in RA.

A phase Ib study of interleukin-2 plus pembrolizumab for patients with advanced melanoma.

High-dose interleukin-2 (HD IL-2) and pembrolizumab are each approved as single agents by the U.S. F.D.A. for the treatment of metastatic melanoma. There is limited data using the agents concurrently. The objectives of this study were to characterize the safety profile of IL-2 in combination with pembrolizumab in patients with unresectable or metastatic melanoma. In this Phase Ib study, patients received pembrolizumab (200 mg IV every 3 weeks) and escalating doses of IL-2 (6,000 or 60,000 or 600,000 IU/kg IV bolus every 8 hours up to 14 doses per cycle) in cohorts of 3 patients. Prior treatment with a PD-1 blocking antibody was allowed. The primary endpoint was the maximum tolerated dose (MTD) of IL-2 when co-administered with pembrolizumab. Ten participants were enrolled, and 9 participants were evaluable for safety and efficacy. The majority of the evaluable participants (8/9) had been treated with PD-1 blocking antibody prior to enrollment. Patients received a median of 42, 22, and 9 doses of IL-2 in the low, intermediate, and high dose cohorts, respectively. Adverse events were more frequent with increasing doses of IL-2. No dose limiting toxicities were observed. The MTD of IL-2 was not reached. One partial response occurred in 9 patients (11%). The responding patient, who had received treatment with an anti-PD-1 prior to study entry, was treated in the HD IL-2 cohort. Although the sample size was small, HD IL-2 therapy in combination with pembrolizumab appears feasible and tolerable. ClinicalTrials.gov, identifier NCT02748564.

Evidence that oncostatin M synergizes with IL-4 signaling to induce TSLP expression in chronic rhinosinusitis with nasal polyps

Oncostatin M (OSM) may promote type 2 inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP) by inducing thymic stromal lymphopoietin (TSLP). We sought to study the impact of OSM on TSLP synthesis and release from nasal epithelial cells (NECs). OSM receptors, IL-4 receptors (IL-4R), and TSLP were evaluated in mucosal tissue and primary NECs from patients with CRSwNP by quantitative PCR and immunofluorescence. Air-liquid interface-cultured NECs were stimulated with cytokines, including OSM, and quantitative PCR, ELISA, Western blot, and flow cytometry were used to assess the expression of OSM receptors, IL-4R, and TSLP. Increased levels of OSM receptor β chain (OSMRβ), IL-4Rα, and TSLP were observed in nasal polyp tissues and primary epithelial cells from nasal polyps of patients with CRSwNP compared with control tissues or cells from control subjects. The level of expression of OSMRβ in tissue was correlated with levels of both IL-4Rα and TSLP. OSM stimulation of NECs increased the expression of OSMRβ and IL-4Rα. Stimulation with IL-4 plus OSM augmented the production of TSLP; the response was suppressed by a signal transducer and activator of transcription 6 inhibitor. Stimulation of NECs with IL-4 plus OSM increased the expression of proprotein convertase subtilisin/kexin 3, an enzyme that truncates and activates TSLP. OSM increases the expression of IL-4Rα and synergizes with IL-4 to induce the synthesis and release of TSLP in NECs. Because the combination of IL-4 and OSM also augmented the expression of proprotein convertase subtilisin/kexin 3, these results suggest that OSM can induce both synthesis and posttranslational processing/activation of TSLP, promoting type 2 inflammation.

Regulation of Cytotoxic Immune Effector Function by AJ3 Probiotic Bacteria in Amyotrophic Lateral Sclerosis (ALS).

Our recent studies indicated that amyotrophic lateral sclerosis (ALS) patients suffer from significantly elevated levels of interferon-gamma (IFN-γ) secretion by natural killer (NK) and CD8+ T cells, which may be responsible for the immune-pathologies seen in central nervous system and in peripheral organs of the patients. In order to counter such elevated induction of IFN-γ in patients we designed a treatment strategy to increase anti-inflammatory cytokine interleukin-10 (IL-10) by the use of probiotic strains which significantly increase the levels of IL-10. Therefore, in this paper we demonstrate disease specific functions of Al-Pro (AJ3) formulated for the adjunct treatment of auto-immune diseases including ALS, and compared the function with CA/I-Pro (AJ4) for the treatment of cancer and viral diseases, and NK-CLK (AJ2) for maintenance of immune balance and promotion of disease prevention. The three different formulations of probiotic bacteria have distinct profiles of activation of peripheral blood mononuclear cells (PBMCs), NK, and CD8+ T cells, and their induced activation is different from those mediated by either IL-2 or IL-2 + anti-CD16 monoclonal antibodies (mAbs) or IL-2 + anti-CD3/CD28 mAbs. IL-2 + anti-CD16 mAb activation of PBMCs and NK cells had the highest IFN-γ/IL-10 ratio, whereas IL-2 combination with sAJ4 had the next highest followed by IL-2 + sAJ2 and the lowest was seen with IL-2 + sAJ3. Accordingly, the highest secretion of IFN-γ was seen when the PBMCs and NK cells were treated with IL-2 + sAJ4, intermediate for IL-2 + sAJ2 and the lowest with IL-2 + sAJ3. The levels of IFN-γ induction and the ratio of IFN-γ to IL-10 induced by different probiotic bacteria formulation in the absence of IL-2 treatment remained much lower when compared to those treated in the presence of IL-2. Of note is the difference between NK cells and CD8+ T cells in which synergistic induction of IFN-y by IL-2 + sAJ4 was significantly higher in NK cells than those seen by CD8+ T cells. Based on these results, sAJ3 should be effective in alleviating auto-immunity seen in ALS since it will greatly regulate the levels and function of IFN-γ negatively, decreasing overactivation of cytotoxic immune effectors and prevention of death in motor neurons.

Intratumoral Gene Transfer of mRNAs Encoding IL12 in Combination with Decoy-Resistant IL18 Improves Local and Systemic Antitumor Immunity.

IL12-based local gene therapy of cancer constitutes an active area of clinical research using plasmids, mRNAs, and viral vectors. To improve antitumor effects, we have experimentally tested the combination of mRNA constructs encoding IL12 and IL18. Moreover, we have used a form of IL18 [decoy-resistant IL18 (DR-18)] which has preserved bioactivity but does not bind to the IL18 binding protein decoy receptor. Both cytokines dramatically synergize to induce IFNγ release from mouse splenocytes, and, if systemically cotransferred to the liver, they mediate lethal toxicity. However, if given intratumorally to B16OVA tumor-bearing mice, the combination attains efficacy against the directly treated tumor and moderate tumor-delaying activity on distant noninjected lesions. Cotreatment was conducive to the presence of more activated CD8+ T cells in the treated and noninjected tumors. In keeping with these findings, the efficacy of treatment was contingent on the integrity of CD8+ T cells and cDC1 dendritic cells in the treated mice. Furthermore, efficacy of IL12 plus DR-18 local mRNA coinjection against distant concomitant tumors could be enhanced upon combination with anti-PD-1 mAb systemic treatment, thus defining a feasible synergistic immunotherapy strategy.

Multiple sclerosis-disease modifying therapies affect humoral and T-cell response to mRNA COVID-19 vaccine.

The mRNA vaccines help protect from COVID-19 severity, however multiple sclerosis (MS) disease modifying therapies (DMTs) might affect the development of humoral and T-cell specific response to vaccination. The aim of the study was to evaluate humoral and specific T-cell response, as well as B-cell activation and survival factors, in people with MS (pwMS) under DMTs before (T0) and after two months (T1) from the third dose of vaccine, comparing the obtained findings to healthy donors (HD). All possible combinations of intracellular IFNγ, IL2 and TNFα T-cell production were evaluated, and T-cells were labelled "responding T-cells", those cells that produced at least one of the three cytokines of interest, and "triple positive T-cells", those cells that produced simultaneously all the three cytokines. The cross-sectional evaluation showed no significant differences in anti-S antibody titers between pwMS and HD at both time-points. In pwMS, lower percentages of responding T-cells at T0 (CD4: p=0.0165; CD8: p=0.0022) and triple positive T-cells at both time-points compared to HD were observed (at T0, CD4: p=0.0007 and CD8: p=0.0703; at T1, CD4: p=0.0422 and CD8: p=0.0535). At T0, pwMS showed higher plasma levels of APRIL, BAFF and CD40L compared to HD (p<0.0001, p<0.0001 and p<0.0001, respectively) and at T1, plasma levels of BAFF were still higher in pwMS compared to HD (p=0.0022).According to DMTs, at both T0 and T1, lower anti-S antibody titers in the depleting/sequestering-out compared to the enriching-in pwMS subgroup were found (p=0.0410 and p=0.0047, respectively) as well as lower percentages of responding CD4+ T-cells (CD4: p=0.0394 and p=0.0004, respectively). Moreover, the depleting/sequestering-out subgroup showed higher percentages of IFNγ-IL2-TNFα+ T-cells at both time-points, compared to the enriching-in subgroup in which a more heterogeneous cytokine profile was observed (at T0 CD4: p=0.0187; at T0 and T1 CD8: p =0.0007 and p =0.0077, respectively). In pwMS, humoral and T-cell response to vaccination seems to be influenced by the different DMTs. pwMS under depleting/sequestering-out treatment can mount cellular responses even in the presence of a low positive humoral response, although the cellular response seems qualitatively inferior compared to HD. An understanding of T-cell quality dynamic is needed to determine the best vaccination strategy and in general the capability of immune response in pwMS under different DMT.

032 Sebaceous glands are actively and differentially involved in the pathogenesis of atopic dermatitis and psoriasis as revealed by spatial transcriptomics

The primary function of sebaceous glands (SGs) is to produce the lipid rich sebum and thereby contribute to hair and skin lubrication. Recent findings however revealed that SGs may have immunoregulatory functions as well. We performed spatial transcriptomics (ST) on lesional and autologous non-lesional human skin samples of patients with psoriasis (PsO), atopic dermatitis (AD). Differentially expressed genes were identified followed by pathway enrichment analysis. Finally, a meta-analysis was done using RNAseq data from SZ95 human sebocytes treated with a combination of IL17 and TNFa to mimic the effect of a PsO-like microenvironment.

CD8+ T Cells from Patients with CLL Show Evidence of Granzyme B and Perforin Cytotoxic Capacity, Which Is Enhanced upon Exposure to Exogenous IL2 and/or IL21

CD8+ T Cells from Patients with CLL Show Evidence of Granzyme B and Perforin Cytotoxic Capacity, Which Is Enhanced upon Exposure to Exogenous IL2 and/or IL21

Impact of IL-15 and latency reversing agent combinations in the reactivation and NK cell-mediated suppression of the HIV reservoir

Inhibitors of histone deacetylases (HDACis) are major latency reversing agent (LRA) candidates in ‘shock and kill’ strategies to eradicate the HIV reservoir in infected patients. The poor achievements of initial HDACi-based trials and subsequent studies have highlighted the need for more efficient approaches such as combinatory and immunostimulating therapies. Here we studied combinations of IL-15 with pan-HDACi (Vorinostat, Romidepsin, Panobinostat) or class I selective-HDACi (Entinostat) with or without a PKC agonist (Prostratin) for their impact on in vitro reactivation and NK cell-mediated suppression of latent HIV. Results showed that pan-HDACis but not Entinostat reduced NK cell viability and function; yet, combined IL-15 reverted the negative effects of pan-HDACis except for Panobinostat. All HDACis were ineffective at reactivating HIV in a CD4+ T cell model of latency, with pan-HDACis suppressing spontaneous and IL-15- or Prostratin-induced HIV release, while IL-15 + Prostratin combination showed maximal activity. Moreover, Panobinostat impaired STAT5 and NF-κB activation by IL-15 and Prostratin, respectively. Finally, by using effectors (NK) and targets (latently infected CD4+ T cells) equally exposed to drug combinations, we found that IL-15-mediated suppression of HIV reactivation by NK cells was inhibited by Panobinostat. Our data raise concerns and encouragements for therapeutic application of IL-15/LRA combinations.

Abscopal Responses to Radiation Combined with Anti-PD-1 and CD122-Directed IL-2/Anti-IL-2 Complexes

<h3>Purpose/Objective(s)</h3> Early clinical trials have provided evidence for RT-induced systemic effects in conjunction with αPD-1 or IL-2 in metastatic patients, but strong abscopal responses are clinically rare. Dual combinations of αPD-1 with more effective and less toxic IL-2 derivatives, e.g., CD122-directed pegylated IL-2, are also currently under investigation. Whether a combination of RT, αPD-1, and CD122-directed IL-2/anti-IL-2 complexes (IL-2c) can increase abscopal effects against established non-irradiated tumors is unknown. Also, in-depth analyses of the differentiation of tumor-specific CD8⁺ T cells have not yet been reported for αPD-1/IL-2c in combination with RT. We investigated how adding IL-2c to hRT/αPD1 affects tumor-specific CD8⁺ T cell differentiation in mouse tumor models and the potential of this triple combination to enhance the abscopal effect compared to the respective dual treatments. <h3>Materials/Methods</h3> Mice bearing bilateral tumors were treated with two fractions of 8 Gy (C51 colon carcinoma model) or 12 Gy (B16 melanoma model); αPD1 was given weekly; IL-2c was given for five consecutive days. CD8 T cell-depleting and CXCR3-blocking antibodies were used to determine if the therapeutic effects depend on CD8⁺ and CXCR3⁺ T cells. Differentiation stages of tumor-specific CD8⁺ T cells in tumor-draining lymph nodes, spleen, blood, and tumors were determined by flow cytometry using MHC-I tetramers and various antibodies. <h3>Results</h3> The abscopal effect was significantly stronger in triple-treated mice compared to mice treated with RT/αPD1 (C51 model: p < 0.01; B16 model: p < 0.05), RT/IL-2c (C51 model: p < 0.01; B16 model: p < 0.001) or αPD1/IL-2c (C51 model: p < 0.0001, B16 model: p < 0.01). Moreover, triple therapy improved survival and resulted in complete cures of 3/12 mice in the C51 model and 2/12 mice in the B16 model. These anti-tumor effects were associated with dramatic expansion of tumor-specific CD8⁺ T cells. Undifferentiated stem-like and effector-like but not terminally differentiated exhausted cells particularly strongly increased. Moreover, IL-2c induced CXCR3 expression on tumor-specific CD8⁺ T cells. Both CD8⁺ (C51 model: p < 0.0001; B16 model: p < 0.01) and CXCR3⁺ (C51 model: p < 0.0001) T cells were crucial for the RT-induced abscopal effect upon RT/αPD-1/IL-2c treatment. <h3>Conclusion</h3> RT/αPD-1/IL-2c triple treatment resulted in superior local and systemic expansion of tumor-specific CD8⁺ T cells with stem- and effector-like phenotypes. Also, IL-2c strongly increased CXCR3⁺ CD8⁺ T cells that were associated with pronounced abscopal responses in models with an established non-irradiated tumor resistant to αPD-1/IL-2c and only transiently responding to RT/αPD-1 or RT/IL-2c. Therefore, such triple combinations appear promising for clinical evaluation in metastatic patients.

OPTIMIZED PROTOCOLS OF EXPANSION OF PERIPHERAL BLOOD-DERIVED δT-CELLS FOR THE ESTABLISHMENT OF AN OFF-THE-SHELF ADVANCED CELL THERAPY AGAINST CANCER

The use of autologous T cells expressing chimeric antigen receptors (CAR) has revolutionized the treatment of hematological malignancies. However, the use of allogeneic CAR-T cells offers many advantages over autologous therapies, including the immediate availability of cryopreserved batches for infusion and the use of healthy donor cells since it is possible to obtain high amounts of fully functional cells. Moreover, this strategy also allows for the scaling up of the production of CAR-T cells resulting in cost reduction. Cells that do not express TCR αβ, such as gamma delta (γδ) T, are an alternative source to allow widespread allogeneic therapy possible. Their ability to recognize targets in an MHC-independent manner and the expression of innate immunity receptors increases the potential of using these cells in immunotherapies. Aiming to improve the effectiveness of γδ T-cell-based immunotherapies against tumors, we tested various optimization strategies. The most widely used protocol for selectively expanding Vδ2T cells relies on zoledronic acid (ZOL) stimulation of PBMCs in combination with IL-2 or/and IL-15 cytokines. Here, we tested different concentrations of IL-2 (100 and 1,000 U/mL) and IL-15 (12.5 and 100 ng/mL) with 5 μM zoledronic acid. In addition, we compared cell expansion in three defined cell culture media, OpTmizer T Cell Expansion SFM, X-vivo10, and TexMACS (supplemented with 2% AB serum). A total of twenty-four different combinations of IL-2, IL-15, and media were tested in the present study.After twelve days of culture, cells were counted and labelled with anti-CD3, anti-CD8, anti-CD4, anti-Vδ2, anti-PD1, anti-CD69, and anti-NKG2D antibodies for flow cytometry analysis. Our results demonstrated that although TexMACS medium is capable of supporting T-cell activation and expansion, it was not optimal for maximal expansion of Vδ2T cells (fold expansion 5.99 ± 1.61). However, the fold expansion was similar in OpTmizer and X-vivo10 media (fold expansion 21.38 ± 5.13 and 18.37 ± 5.42, respectively). Among the medium supplementation strategies, cultivation in OpTmizer combined with 100 U/mL IL-2 + 12.5 ng/mL IL-15 led to highest expansion index (32.4-fold). As for the activation markers of Vδ2T cells, the frequency of NKG2D+ cells was similar for all conditions tested (above 85%). However, the percentage of CD69+ cells was higher in cells cultured in TexMACS medium compared to OpTmizer and X-vivo10 media (81.6±5.3, 69±9.9, 60.2±7.2, respectively). It is known that the Programmed Cell Death-1 receptor (PD-1) plays an important role in regulating immune cell function. We examined the expression of PD-1 after twelve days of expansion. We observed lower levels of PD-1 in cells expanded in X-vivo10 medium supplemented with 1,000 U/mL IL-2 + 100 ng/mL IL-15, whereas levels of expression were up-regulated significantly when cells were cultivated in the same conditions without IL-15 (28.7% versus 70.6%). Cells expanded in either OpTimizer or TexMACS demonstrated a similar frequency to PD-1 positive cells (41±13% and 49.7%±9.5). In conclusion, we reported an optimized protocol to improve the expansion and the quality of Vδ2 T cells. These findings set the groundwork for the establishment of an off-the-shelf advanced cellular immunotherapy using this alternative population of T cells.

PD-1 combination therapy with IL-2 modifies CD8+ T cell exhaustion program.

Combination therapy with PD-1 blockade and IL-2 is highly effective during chronic lymphocytic choriomeningitis virus infection1. Here we examine the underlying basis for this synergy. We show that PD-1+IL-2 combination therapy, in contrast to PD-1 monotherapy, substantially changes the differentiation program of the PD-1+TCF1+ stem-like CD8+T cells and results in the generation of transcriptionally and epigenetically distinct effector CD8+T cells that resemble highly functional effector CD8+T cells seen after an acute viral infection. The generation of these qualitatively superior CD8+ T cells that mediate viral control underlies the synergy between PD-1 and IL-2. Our results show that the PD-1+TCF1+ stem-like CD8+ T cells, also referred to as precursors of exhausted CD8+ T cells, are not fate-locked into the exhaustion program and their differentiation trajectory can be changed by IL-2 signals. These virus-specific effector CD8+ T cells emerging from the stem-like CD8+ T cells after combination therapy expressed increased levels of the high-affinity IL-2 trimeric (CD25-CD122-CD132) receptor. This was not seen after PD-1 blockade alone. Finally, we show that CD25 engagement with IL-2 has an important role in the observed synergy between IL-2 cytokine and PD-1 blockade. Either blocking CD25 with an antibody or using a mutated version of IL-2 that does not bind to CD25 but still binds to CD122 and CD132 almost completely abrogated the synergistic effects observed after PD-1+IL-2 combination therapy. There is considerable interest in PD-1+IL-2 combination therapy for patients with cancer2,3, and our fundamental studies defining the underlying mechanisms of how IL-2 synergizes with PD-1 blockade should inform these human translational studies.

The effect of serum IL-2 levels on the prognosis of primary biliary cholangitis-related liver failure and the preliminary exploration of its mechanism.

BackgroundIn primary biliary cholangitis (PBC), the levels of serum IL-2 were involved in liver inflammation and immune changes. This study aimed to investigate the prognostic significance of serum IL-2 combined with total bilirubin (TBIL) in liver failure and cytokine changes during the disease.MethodsA total of 160 PBC patients treated with UDCA were included. Parameters at admission were collected, and the COX regression model was used to predict independent risk factors associated with PBC disease progression. We identified the optimal cut-off values and prognosis effects of serum IL-2 and TBIL based on the time-dependent receiver operating characteristic (ROC) curve. We also analyzed the incidence of liver failure with Kaplan-Meier survival analysis. In addition, the changes of cytokines (mainly IL-2) in liver tissues and blood samples from 11 patients with end-stage PBC liver failure and five healthy controls were examined.ResultsAge, IL-2, ALB, γ-GT, ALP, TBIL, Hb, TBA, WBC, and PLT, as well as anti-Sp100, were found to be independent risk factors in PBC patients with liver failure. Patients with decreased serum IL-2 levels and increased TBIL levels have a significantly higher incidence of liver failure and a worse prognosis. Patients with advanced PBC liver failure after liver transplantation exhibited a significant decrease in levels of serum IL-2 and a relatively immunosuppressed status.ConclusionsThe combination of serum IL-2 and TBIL can be a predictor of the progression of liver failure in patients with primary biliary cholangitis, and it is likely to be related to the expression of GM-CSF and G-CSF.

35128 Cerebrovascular accident events associated with IL-23 inhibition: Pharmacovigilance analysis of the Food and Drug Administration Adverse Event Reporting System (FAERS) from the RADAR (Research on Adverse Drug Events And Reports) Program

Background: IL-23 inhibitors, risankizumab, guselkumab, and tildrakizumab, are approved systemic therapies for adults with moderate-to-severe plaque psoriasis. Although an increased risk for cerebrovascular accidents (CVAs) has been reported with exposure to combined IL-12/IL-23 inhibition in patients with cardiovascular risk, such evidence for IL-23 inhibition as monotherapy remains unaddressed. The aim of this study was to determine if a safety signal is detectable in the FAERS database for IL-23 inhibitors and subsequent CVAs.

Significant difference in Th1/Th2 paradigm induced by tuberculosis-specific antigens between IGRA-positive and IGRA-negative patients.

False negative interferon-γ release assay (IGRA) results constitute the major dilemma for the diagnosis of tuberculosis (TB) infections. Herein, we conducted a cohort study to compare the host immunological response to TB-specific antigens between active TB patients with positive and negative IGRA results and control groups. A total of 274 laboratory-confirmed TB patients were included in our analysis, consisting of 221 were IGRA positive and 53 were IGRA negative. Patients with the elderly were identified as an independent risk factor for negative IGRA results. In addition, the elevated level of IL-4 and the decreased levels of IFN-γ, IL-2, IL-6, IL-1β, and IL-12 in IGRA negative TB relative to IGRA positive TB group, demonstrating a significant difference in Th1/Th2 paradigm between two groups. The IFN-γ&IL-2 based assay could correctly identify 247 out of 307 MTB-infected individuals [271 TB patients and 36 individuals with latent TB infection (LTBI)], demonstrating a sensitivity of 80.5%. Then the IFN-γ and IL-4 were applied to distinguish healthy control and IGRA-negative group. When using the stepwise algorithm, the sensitivity for detecting Mycobacterium tuberculosis (MTB) infections was significantly increased from 80.5% to 89.6%. Additionally, patients with negative IGRA results had a conversion to culture-negative status longer than those with positive IGRA results. In conclusion, a stepwise algorithm outperforms IGRA assays to accurately identify MTB infections by the combination IFN-γ, IL-2, and IL-4. Further study is needed to evaluate the accuracy of our diagnostic algorithm in the LTBI population.

Abstract 573: Ex-vivo inhibition of CBL-B with a novel small molecule inhibitor, NX-0255, enhances persistence and anti-tumor activity of adoptively transferred CD8+ T cells in mouse tumor models

Abstract Adoptive cell transfer (ACT) involving autologous tumor-specific lymphocytes (TIL) has shown promising results in the treatment of advanced cancer. Poor in vitro cell expansion, inefficient T-cell migration and T cell exhaustion in the tumor microenvironment greatly limits the broader application of this approach. The E3 ubiquitin ligase Casitas B-lineage lymphoma b (CBL-B) is highly expressed in T cells, where it limits cell activation following TCR engagement, therefore functioning as an important intracellular checkpoint that limits T cell mediated anti-tumor responses. We have developed NX-0255 a highly potent small molecule inhibitor of CBL-B that increases TCR-mediated activation of T cells in the presence or absence of CD28 co-stimulation. Here we used the OT-1 ACT/E.G7-OVA lymphoma and the Pmel-1 ACT/B16 melanoma tumor models to investigate whether adding NX-0255, during the in vitro expansion of tumor-specific T cells would have favorable effects on their ability to reject tumors following adoptive transfer in vivo. OT-1 CD8+ T cells were expanded in vitro using anti-CD3 stimulation and either NX-0255 alone, IL-2 alone, or NX-0255 combined with IL-2 and subsequently transferred in vivo to mice bearing established E.G7-OVA. ACT of OT-1 CD8+ T cells cultured with the combination of NX-0255 plus IL-2 demonstrated superior anti-tumor activity against E.G7-OVA lymphoma tumors, resulting in significant improvement in survival when compared to mice receiving OT-1 CD8+ T cells cultured with NX-0255 alone or IL-2 alone. Importantly, OT-1 CD8+ T cells cultured in the presence of NX-0255 or the combination of NX-0255 plus IL-2 were found at an increased frequency in the blood and in the tumor and persisted longer in circulation when compared to cells cultured with IL-2 alone. A lower percentage of the tumor-infiltrating OT-1 cells were triple-positive for exhaustion markers PD1+TIM3+LAG3+ expression when cultured with NX-0255 alone or the combination of NX-0255 and IL-2 compared to culture with IL-2 alone. Similarly, ACT of Pmel-1 CD8+ T cells cultured with the combination of NX-0255 plus IL-2 provides a robust and durable anti-tumor response compared to mice receiving Pmel-1 CD8+ T cells cultured with IL-2 alone in the aggressive B16-OVA model. Flow cytometry analysis showed that Pmel-1 CD8+ T cells cultured in the presence of NX-0255 plus IL-2 were found at an increased frequency in the blood and showed an increased central-memory phenotype (CD44+CD62L+) after adoptive transfer when compared to cells cultured with IL-2 alone. Collectively, these data suggest that adding the CBL-B inhibitor, NX-0255, during the in vitro expansion of tumor-specific T cells increases the frequency and absolute numbers of less exhausted CD8+ memory T-cells, increasing their in vivo persistence and ability to infiltrate the tumor. Citation Format: Marilena Gallotta, Jose Gomez Romo, Alexandra Borodovsky, Austin Tenn-McClellan, Jennifer Stokes, Jennifa Gosling, Gwenn M. Hansen, Arthur Sands, Ryan Rountree, Cristiana Guiducci. Ex-vivo inhibition of CBL-B with a novel small molecule inhibitor, NX-0255, enhances persistence and anti-tumor activity of adoptively transferred CD8+ T cells in mouse tumor models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 573.

Abstract 584: Driving anti-tumor activity in solid tumors with controlled arming of allogeneic CAR-NK cells

Abstract Recent successes with cell therapies, including CAR-T and CAR-NK cells, for hematopoietic cancers have yet to translate into solid tumors. The major obstacle solid tumors present for cell therapy is the highly immunosuppressive tumor microenvironment (TME), which can impair the function of endogenous as well as therapeutic immune cells. To overcome this challenge, Senti Bio is developing gene circuits to arm CAR-NK cells with multiple cytokines to improve the cytotoxicity and persistence of CAR-NK product candidates. Cytokines, as well as other immune effectors, can act in autocrine or paracrine manner, benefiting the CAR-NK cells as well as potentially engaging the local immune system in the TME. Secreted cytokines can be widely distributed and stimulate other immune cells in the TME, however this is often associated with systemic toxicity as well as reduced impact on the CAR-NK cells. On the other hand, membrane-bound cytokines result in a localized and potent stimulation of the CAR-NK cells but have limited impact on the broader TME. Since IL-15 is known to stimulate NK cell survival and function, Senti Bio has created a novel calibrated release (cr) technology to specifically optimize IL-15 signaling in its CAR-NK platform. crIL-15 is tethered to the NK cells via a cleavable linker that allows for IL-15 release upon cleavage by a ubiquitously expressed protease on the cell surface of NK cells. The rate of linker cleavage can be calibrated by engineering the sensitivity of the cleavable linker sequence to the cell surface protease, thereby enabling the tuning of the ratio of membrane tethered versus fully secreted protein. We compared the function of the wildtype IL-15 protein with different variants of crIL-15 that have a faster or slower release. We demonstrated that crIL-15 has a more potent function, stimulating pSTAT5 signaling and driving expansion and survival of NK cells. CAR-NK cells armed with crIL-15 significantly outperformed CAR-NK cells that expressed the wildtype IL-15 protein, had enhanced function, and demonstrated significantly improved cytotoxicity over three rounds of serial killing (p&amp;lt;0.0001). In parallel, we armed CAR-NK cells with gene circuits that encoded various combinations of two or more cytokines. In particular, the combination of IL-15 and IL-21 resulted in a synergistic effect, leading to longer survival in the absence of cytokines compared to NK cells armed with IL-15 alone. Furthermore, CAR-NK cells armed with IL-15 + IL-21 had significantly increased activity and cytotoxicity compared to CAR-NK cells armed with either cytokine alone (up to 4-times increased cytotoxicity, p&amp;lt;0.0001) when co-cultured with tumor cells. Overall, our results suggest the advantage of multi-arming CAR-NK cells with cytokines, using controlled release systems and cytokine combinations, resulting in improved NK cell function in solid tumor models. Citation Format: Alba Gonzalez, Michelle Hung, Marcela Guzman, Aldo Sotelo, Nicholas Frankel, Yin Yin Chong, Deepika Kaveri, Poornima Ramkumar, Elizabeth Leitner, Priscilla Wong, Ronni Ponek, Kelly Lee, Alyssa L. Mullenix, Russell M. Gordley, Gary Lee. Driving anti-tumor activity in solid tumors with controlled arming of allogeneic CAR-NK cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 584.