Recombinant Human Interleukin Research Articles

Co-formulation of the rF1V plague vaccine with depot-formulated cytokines enhances immunogenicity and efficacy to elicit protective responses against aerosol challenge in mice.

This study evaluated a depot-formulated cytokine-based adjuvant to improve the efficacy of the recombinant F1V (rF1V) plague vaccine and examined the protective response following aerosol challenge in a murine model. The results of this study showed that co-formulation of the Alhydrogel-adsorbed rF1V plague fusion vaccine with the depot-formulated cytokines recombinant human interleukin 2 (rhuIL-2) and/or recombinant murine granulocyte macrophage colony-stimulating factor (rmGM-CSF) significantly enhances immunogenicity and significant protection at lower antigen doses against a lethal aerosol challenge. These results provide additional support for the co-application of the depot-formulated IL-2 and/or GM-CSF cytokines to enhance vaccine efficacy.

A CD25-biased interleukin-2 for autoimmune therapy engineered via a semi-synthetic organism

BackgroundNatural cytokines are poorly suited as therapeutics for systemic administration due to suboptimal pharmacological and pharmacokinetic (PK) properties. Recombinant human interleukin-2 (rhIL-2) has shown promise for treatment of autoimmune (AI) disorders yet exhibits short systemic half-life and opposing immune responses that negate an appropriate therapeutic index.MethodsA semi-synthetic microbial technology platform was used to engineer a site-specifically pegylated form of rhIL-2 with enhanced PK, specificity for induction of immune-suppressive regulatory CD4 + T cells (Tregs), and reduced stimulation of off-target effector T and NK cells. A library of rhIL-2 molecules was constructed with single site-specific, biorthogonal chemistry-compatible non-canonical amino acids installed near the interface where IL-2 engages its cognate receptor βγ (IL-2Rβγ) signaling complex. Biorthogonal site-specific pegylation and functional screening identified variants that retained engagement of the IL-2Rα chain with attenuated potency at the IL-2Rβγ complex.ResultsPhenotypic screening in mouse identifies SAR444336 (SAR’336; formerly known as THOR-809), rhIL-2 pegylated at H16, as a potential development candidate that specifically expands peripheral CD4+ Tregs with upregulation of markers that correlate with their suppressive function including FoxP3, ICOS and Helios, yet minimally expands CD8 + T or NK cells. In non-human primate, administration of SAR’336 also induces dose-dependent expansion of Tregs and upregulated suppressive markers without significant expansion of CD8 + T or NK cells. SAR’336 administration reduces inflammation in a delayed-type hypersensitivity mouse model, potently suppressing CD4+ and CD8 + T cell proliferation.ConclusionSAR’336 is a specific Treg activator, supporting its further development for the treatment of AI diseases.

Chemerin promotes invasion of oral squamous cell carcinoma by stimulating IL-6 and TNF-α production via STAT3 activation.

Elevated levels of adipokine chemerin have been identified in oral squamous cell carcinoma (OSCC) and found to be associated with metastasis to the cervical lymph nodes. The underlying mechanism through which chemerin affects OSCC progression is unclear. The aims of this study were firstly to determine chemerin levels and cytokine concentrations in serum from patients with OSCC and in OSCC cell cultures, and secondly to observe chemerin effects on OSCC cell cytokine secretion, migration, and invasion in vitro. Serum samples were collected from 20 patients diagnosed with OSCC, including groups with (LN+) and without (LN-) cervical lymph node metastasis. A Luminex liquid suspension assay was used to quantify serum concentrations of 27 types of cytokines. Correlations between chemerin and cytokines (i.e., IL-6, IL-15, GM-CSF, RANTES, TNF-α, and VEGF) were analyzed. ELISAs (enzyme-linked immunosorbent assays) were used to determine concentrations of chemerin and selected cytokines in serum and in supernatants of OSCC cell cultures (SCC9 and SCC25 cell lines). OSCC cells were stimulated with human recombinant chemerin, STAT3 inhibitor, or IL-6 together with TNF-α neutralizing antibodies. Phosphorylated STAT3 protein levels were measured with western blot analysis. OSCC cell migration and invasion were investigated with Transwell assays. Compared to the LN- group, OSCC patients with cervical lymph node metastasis had higher levels of IL-6 (P = 0.006), IL-15 (P = 0.020), GM-CSF (P = 0.036), RANTES (P = 0.032), TNF-α (P = 0.005), VEGF (P = 0.006), and chemerin (P = 0.001). Patients' serum chemerin levels correlated directly with IL-6, GM-CSF, TNF-α, and VEGF levels in OSCC patients. Exogenous recombinant chemerin treatment promoted secretion of IL-6 and TNF-α via activation of STAT3 in OSCC cells. Chemerin induced OSCC-cell migration and invasion, and these effects were reduced by IL-6 and TNF-α neutralizing antibodies. Our findings indicate that chemerin may play a role in advancing OSCC progression by increasing production of IL-6 and TNF-α, perhaps via a mechanism involving STAT3 signaling.

Abstract 6744: Activating anti-MDS immunity with polarized dendritic cell vaccines

Abstract Less than 50% of patients with higher-risk myelodysplastic syndromes (MDS) show clinical response to standard-of-care hypomethylating (HMA) therapy. Significant enthusiasm existed for immunotherapy/HMA combinations for these patients, but studies have failed to deliver on the initial promise. We have demonstrated that patients with MDS have a deficiency in antigen-presenting cells, called CD141Hi dendritic cells (DC). DC-deficient MDS patients have reduced response to HMAs, worse overall survival, and show less response to cancer vaccination. We hypothesized that restoration of this population using a novel DC vaccination approach - alpha-type-1 polarized dendritic cells (αDC1) - might compensate for this deficiency and restore immunity. To generate αDC1s, we collected monocytes from MDS patients and healthy donors (HD) and cultured them for 6 days in vitro in the presence of recombinant human GM-CSF and IL-4 followed by an additional 18-24 hours in the presence of αDC1 maturation factors (poly-I:C/IFNα/IFNγ/TNFα/IL-1β). Overall, we attempted to generate αDC1s from 15 MDS samples; 13/15 exhibited intermediate to very high-risk disease and 10/15 are currently receiving HMA therapy. We successfully cultured cells from 8/15 samples (53%). Of the 8 MDS samples, 5 were collected from patients receiving HMA therapy (62.5%). We were unable to successfully culture αDC1s from the other 5 patients receiving HMA therapy, and thus the effect of HMA therapy on aDC1 generation remains unclear. To test the function of MDS αDC1s, we focused on two signals necessary to activate immune responses: 1) the expression of co-stimulatory molecules and 2) the production of IL-12p70. Flow cytometric analysis on αDC1s and immature DCs from MDS samples revealed intra-patient variation in the fold-change surface expression of CD40/80/83/86 and HLA-DR proteins. Additionally, there was a trend towards decreased up-regulation of CD80 and CD86 in MDS specimens compared to HD. To assess production of IL-12p70, we stimulated immature DCs and αDC1s with CD40L and performed ELISA analysis on the media supernatant. We found that 3 out of 4 samples could produce IL-12p70 (range 27 - 5,480 pg/ml). To date, our results suggest that generation of MDS patient-derived αDC1 cells is feasible and additional work is being performed to fully characterize their ability to activate anti-MDS immune responses. Since αDC1s have an established safety profile in patients with solid tumors, we anticipate that we will be able to rapidly translate our results to the clinic. Citation Format: Daniel Alvarado, Jennifer Peresie, Adam Brinkman, Cheryl Allen, Weijian Jiang, Pawel Kalinski, Tiffany Tanaka, Elizabeth Griffiths, Michael Nemeth. Activating anti-MDS immunity with polarized dendritic cell vaccines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6744.

Abstract 2837: Conservation of JAK-STAT signaling in canine lymphocytes responding to human IL-6, IL-7, and IL-1 alpha

Abstract Dogs share physiological similarities with humans, positioning them as valuable models for studying the efficacy and safety of drugs and their underlying mechanisms of action. The JAK-STAT pathway, a highly conserved signaling pathway across species, including humans and dogs, presents an opportunity to investigate the therapeutic potential of cytokines that utilize this pathway. In this study, we aimed to evaluate the functional activity of three canine cytokines on canine cells. To assess stimulation of the JAK/STAT pathway, we used a flow cytometry assay that measures phospho-STAT in activated canine or human lymphocytes in whole blood specimens. Testing of commercially available human and canine IL-6 proteins revealed that canine lymphocytes respond poorly to most canine IL-6 products, whereas all recombinant human IL-6 products stimulated STAT phosphorylation in canine lymphocytes, despite sharing low sequence similarity with canine IL-6. In human T cells, both canine IL-6 and human IL-6 stimulated STAT phosphorylation, demonstrating biological activity from the canine IL-6 products. Several JAK inhibitors inhibited cytokine-induced STAT phosphorylation in both canine and human CD4 T-cells, consistent with JAK inhibition, but targeting the IL-6 receptor with tocilizumab only blocked IL-6-induced STAT phosphorylation in human but not canine CD4 T-cells in whole blood. These findings demonstrate the potential of our assay system to assess cross-species cytokine reactivity, determine if JAK/STAT inhibitors used clinically might be useful in treating inflammatory conditions in dogs, and identify novel canine-specific inhibitors. Additionally, we explored the induction of IL-8 by human and canine IL-1 alpha in IL-1 alpha sensitive human cells. Human IL-1 alpha failed to stimulate a canine IL-1 alpha sensitive cell line, suggesting species-specific differences in IL-1 alpha activity. Furthermore, we discovered that canine IL-7 and human IL-7 are species-specific. In summary, this proof-of-concept study highlights the capability to assess the activation of STATs and pathway inhibition by JAK inhibitors in canine whole blood using flow cytometry. We confirmed that human IL-6 stimulates JAK/STAT signaling in canine CD4 T-cells. Our results also revealed significant differences in species cross-reactivity of human IL-6, IL-7, and IL-1 alpha, underscoring the importance of species-specific investigations. Leveraging the similarities and differences between canine and human cytokines targeting the JAK-STAT pathway can enhance drug development efforts and contribute to the advancement of safer and more effective therapies for both humans and pet dogs with similar diseases. This study was funded by NCI Contract No. 75N91019D00024. Citation Format: King Leung Fung, Melissa L. Breiner, James B. Mitchell, Ralph E. Parchment. Conservation of JAK-STAT signaling in canine lymphocytes responding to human IL-6, IL-7, and IL-1 alpha [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2837.

Abstract 7181: Low dose interleukin-6 (SON-080) for neuropathies: Toxicology and clinical plans

Abstract Neuropathies are conditions in which peripheral nerves degenerate, resulting in sensory and motor symptoms that can profoundly affect the patients’ quality of life. Chemotherapy-induced peripheral neuropathy (CIPN) is induced by most antineoplastic agents, affecting cancer patients during or following completion of treatment. Neuropathy-specific pain medication is most often inefficient against pain, can cause major side effects that limit their use, do not address non-pain related symptoms, and do not stop CIPN progression. Most evidence suggests that physical exercise is the most efficient approach to reduce neuropathy symptoms and potentially, progression. Other publications have causally linked exercise, through the ability of contracting muscles to release low levels of interleukin-6 into the bloodstream thereby activating several metabolic and physiological pathways that help regenerate muscle and nerve tissue, affect glucose homeostasis, increase lipolysis, improve microvascular blood flow and reduce inflammation. Preclinical disease models of CIPN and diabetic peripheral neuropathy (DPN) have confirmed that IL-6 administered at low doses is capable of stimulating peripheral nerve growth, thereby ameliorating motor and sensory functions and normalizing the associated pain or sensation disturbance of neuropathy. The maximum tolerated (MTD) dose of recombinant human IL-6 (rhIL-6) has been established as a treatment for thrombocytopenia in hundreds of cancer patients using the drug product that was produced in the 1990’s (Process A) dosed intravenously (IV) or subcutaneously (SC). We have developed a cGMP compliant version of rhIL-6 (SON-080) using a state-of-the-art process (Process B) that meets current regulatory guidelines for cell lines and processes. An analytical comparison of SON-080 with Process A rhIL-6 concluded that both drugs are highly comparable for at least 14 different key physicochemical characteristics. Therefore, we expect similar in vivo behavior with Process B material as compared with the Process A molecule. In order to support clinical plans for the safety and toxicity of rhIL-6, a dose range and schedule of administration that matches the current clinical protocol was performed in a cynomolgus monkey primate toxicology model. Under these conditions, SON-080 was found safe and well tolerated with a No Adverse Effect Levels (NOAEL) of 30µg/kg, the highest dose tested. On this basis, a fully controlled Phase 1b/2a clinical study, SB211, is ongoing to evaluate safety, tolerability, and efficacy of subcutaneous SON-080 dosage and administration schedule that targets an exposure mirroring the endogenous release levels elicited by moderate to heavy exercise. Confirmation of safety in the first portion of the trial will pave the way for efficacy evaluation with the objective to provide CIPN patients with a novel, safe, and effective treatment for painful neuropathies. Citation Format: Susan Dexter, Gael Hedou, Richard T. Kenney, Darrel J. Rezac, Pankaj Mohan. Low dose interleukin-6 (SON-080) for neuropathies: Toxicology and clinical plans [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7181.

Abstract 37: IL-4 drives CART cell exhaustion in a CD4 independent manner

Abstract While chimeric antigen receptor T (CART) cell therapy has shown remarkable success, the development of exhaustion limits durable response. We identified a role for interleukin (IL)-4 in the development of CART cell exhaustion through three independent approaches including: 1) a genome-wide CRISPR knockout screen using healthy donor CART cells in an in vitro model for exhaustion, 2) RNA and ATAC sequencing on freshly produced and chronically stimulated healthy donor CART cells, and 3) RNA and ATAC sequencing on pre-infusion CART cell products from responders and non-responders in the Zuma-1 clinical trial that led to the FDA approval of axi-cel. Further, in vitro validation studies revealed that CD19 directed CART (CART19) cells chronically stimulated in the presence of human recombinant IL-4 (hrIL-4) displayed signs of exhaustion such as 1) decreased proliferation (p = 0.01), 2) increased coexpression of inhibitory receptors (p = 0.01), and 3) decreased production of IL-2 and interferon (IFN)-γ (p= 0.02, p = 0.002). Encouragingly, CART19 cells combined with an IL-4 monoclonal antibody improved antitumor activity (p = 0.045) and expansion (p = 0.01) while also decreasing the co-expression of inhibitory receptors (p = 0.02) in a mantle cell lymphoma xenograft mouse model. Building on these results, we asked if IL-4 driven exhaustion results from a direct impact of IL-4 on CART cells. To test this, we used a tumor-free assay where CART19 cells were chronically stimulated with CD19 beads in the presence of hrIL-4 or diluent. CART cells treated with hrIL-4 displayed an exhausted phenotype characterized by increased co-expression of inhibitory receptors (p = 0.04) and decreased production of IL-2 (p = 0.01). Next, we asked if IL-4 driven CART cell exhaustion is dependent on the costimulatory domain. We tested the impact of IL-4 on both CD28ζ and 41BBζ costimulated CART19 cells. Similar to our previous studies with CART19-28ζ cells, chronic stimulation of CART19-BBζ cells in the presence of hrIL-4 enhanced the exhausted phenotype as seen by increased co-expression of inhibitory receptors (p = 0.04) and decreased production of IL-2 and IFN-γ (p = 0.08 and p = 0.007). Finally, we asked if IL-4 induces exhaustion independently of its classic role in Th2 polarization of CD4 CART cells. Following CART production, we isolated CD8 cells and chronically stimulated them in the presence of hrIL-4 or diluent. CD8 CART cells treated with hrIL-4 displayed an enhanced exhausted profile as seen by 1) decreased proliferative ability (p < 0.0001), 2) increased co-expression of inhibitory receptors (p = 0.01), and 3) decreased production of IL-2 and IFN-γ (p < 0.0001, p = 0.004). Together, our data indicates a novel role for IL-4 in the development of CART cell exhaustion that is independent of tumor cells, costimulatory domain, and CD4 cells. As such, we believe IL-4 neutralization may be a widely applicable and actionable approach to improve the durable response to CART cell therapy. Citation Format: Carli M. Stewart, Elizabeth L. Siegler, Truc N. Huynh, R. Leo Sakemura, Brooke Kimball, Long Mai, Kun Yun, James H. Girsch, Jennifer Feigin, Omar Gutierrez Ruiz, Makena Rodriguez, Ekene Ogbodo, Ismail Can, Claudia Manriquez Roman, Olivia Sirpilla, Hong Xia, Jenny Kim, Justin Budka, Mike Mattie, Nathalie Scholler, Simone Filosto, Saad S. Kenderian. IL-4 drives CART cell exhaustion in a CD4 independent manner [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 37.

Multiply restimulated human cord blood-derived Tregs maintain stabilized phenotype and suppressive function and predict their therapeutic effects on autoimmune diabetes

BackgroundRegulatory T cells (Tregs) are involved in the maintenance of immune homeostasis and immune regulation. Clinical trials on the adoptive transfer of Tregs have been ongoing for > 10 years. However, many unresolved issues remain in the production of readymade Treg products and selection of patients. Hence, this study aimed to develop a method to expand off-the-shelf Tregs derived from umbilical cord blood (UCB-Tregs) in vitro without changing their phenotype and inhibitory function. In addition, the study intended to design an approach to precisely select patients who are more likely to benefit from the adoptive Treg transfer therapy.MethodsUCB-Tregs were isolated and cultured in a medium containing human recombinant IL-2 and rapamycin and then multiply restimulated with human T-activator CD3/CD28 dynabeads. The phenotype and suppressive capacity of Tregs were assessed on days 18 and 42. The relationship between the suppressive function of UCB-Tregs in vitro and clinical indicators was analyzed, and the ability of the in vitro suppressive capacity to predict the in vivo therapeutic effects was evaluated.ResultsUCB-Tregs expanded 123-fold and 5,981-fold at 18 and 42 days, respectively. The suppressive function of UCB-Tregs on the proliferation of immune cells at 42 days was not significantly different compared with that of UCB-Tregs obtained at 18 days. The suppression rate of UCB-Tregs to PBMCs was negatively correlated with the course of diabetes. Moreover, the high-suppression group exhibited a better treatment response than the low-suppression group during the 12-month follow-up period.ConclusionsMultiply restimulated UCB-Tregs expanded at a large scale without any alterations in their classical phenotypic features and inhibitory functions. The suppressive function of Tregs in vitro was negatively correlated with the disease duration. The present study revealed the possibility of predicting the in vivo therapeutic effects via the in vitro inhibition assay. Thus, these findings provided a method to obtain off-the-shelf Treg products and facilitated the selection of patients who are likely to respond to the treatment, thereby moving toward the goal of precision treatment.

Interleukin-2-induced skin inflammation.

Recombinant human IL-2 has been used to treat inflammatory diseases and cancer; however, side effects like skin rashes limit the use of this therapeutic. To identify key molecules and cells inducing this side effect, we characterized IL-2-induced cutaneous immune reactions and investigated the relevance of CD25 (IL-2 receptor α) in the process. We injected IL-2 intradermally into WT mice and observed increases in immune cell subsets in the skin with preferential increases in frequencies of IL-4- and IL-13-producing group 2 innate lymphoid cells and IL-17-producing dermal γδ Tcells. This overall led to a shift toward type 2/type 17 immune responses. In addition, using a novel topical genetic deletion approach, we reduced CD25 on skin, specifically on all cutaneous cells, and found that IL-2-dependent effects were reduced, hinting that CD25 - at least partly - induces this skin inflammation. Reduction of CD25 specifically on skin Tregs further augmented IL-2-induced immune cell infiltration, hinting that CD25 on skin Tregs is crucial to restrain IL-2-induced inflammation. Overall, our data support that innate lymphoid immune cells are key cells inducing side effects during IL-2 therapy and underline the significance of CD25 in this process.

Altered IL-7 signaling in CD4+ T cells from patients with visceral leishmaniasis.

CD4+ T cells play a central role in control of L. donovani infection, through IFN-γ production required for activation of macrophages and killing of intracellular parasites. Impaired control of parasites can in part be explained by hampered CD4+ T cells effector functions in visceral leishmaniasis (VL) patients. In a recent studies that defined transcriptional signatures for CD4+ T cells from active VL patients, we found that expression of the IL-7 receptor alpha chain (IL-7Rα; CD127) was downregulated, compared to CD4+ T cells from endemic controls (ECs). Since IL-7 signaling is critical for the survival and homeostatic maintenance of CD4+ T cells, we investigated this signaling pathway in VL patients, relative to ECs. CD4+ T cells were enriched from peripheral blood collected from VL patients and EC subjects and expression of IL7 and IL7RA mRNA was measured by real time qPCR. IL-7 signaling potential and surface expression of CD127 and CD132 on CD4+ T cell was analyzed by multicolor flow cytometry. Plasma levels of soluble IL-7 and sIL-7Rα were measured by ELISA. Transcriptional profiling data sets generated previously from our group showed lower IL7RA mRNA expression in VL CD4+ T cells as compared to EC. A significant reduction was, however not seen when assessing IL7RA mRNA by RT-qPCR. Yet, the levels of soluble IL-7Rα (sIL-7Rα) were reduced in plasma of VL patients compared to ECs. Furthermore, the levels of soluble IL-7 were higher in plasma from VL patients compared to ECs. Interestingly, expression of the IL-7Rα protein was higher on VL patient CD4+ T cells as compared to EC, with activated CD38+ CD4+ T cells showing higher surface expression of IL-7Rα compared to CD38- CD4+ T cells in VL patients. CD4+ T cells from VL patients had higher signaling potential baseline and after stimulation with recombinant human IL-7 (rhIL-7) compared to EC, as measured by phosphorylation of STAT5 (pSTAT5). Interestingly, it was the CD38 negative cells that had the highest level of pSTAT5 in VL patient CD4+ T cells after IL-7 stimulation. Thus, despite unaltered or potentially lowered IL7RA mRNA expression by CD4+ T cells from VL patients, the surface expression of the IL-7Rα was higher compared to EC and increased pSTAT5 was seen following exposure to rhIL-7. Accordingly, IL-7 signaling appears to be functional and even enhanced in VL CD4+ T cells and cannot explain the impaired effector function of VL CD4+ T cells. The enhanced plasma IL-7 may serve as part of homeostatic feedback mechanism regulating IL7RA expression in CD4+ T cells.

Understanding the pharmacokinetic journey of Fc-fusion protein, rhIL-7-hyFc using complementary approach of two analytical methods, accelerator mass spectrometry and ELISA.

Antibody-based therapeutics (ABTs), including monoclonal/polyclonal antibodies and fragment crystallizable region (Fc)-fusion proteins, are increasingly used in disease treatment, driving the global market growth. Understanding the pharmacokinetic (PK) properties of ABTs is crucial for their clinical effectiveness. This study investigated the PK profile and tissue distribution of efineptakin alfa, a long-acting recombinant human interleukin-7 (rhIL-7-hyFc), using enzyme-linked immunosorbent assay (ELISA) and accelerator mass spectrometry (AMS). Totally, four rats were injected intramuscularly with 1mg/kg of rhIL-7-hyFc containing 14C-rhIL-7-hyFc, which was prepared via reductive methylation. Serum total radioactivity (TRA) and serum rhIL-7-hyFc concentrations were quantified using AMS and ELISA, respectively. The TRA concentrations in organs were determined by AMS. Serum TRA peaked at 10hours with a terminal half-life of 40hours. The rhIL-7-hyFc exhibited a mean peak concentration at around 17hours and a rapid elimination with a half-life of 12.3hours. Peak concentration and area under the curve of TRA were higher than those of rhIL-7-hyFc. Tissue distribution analysis showed an elevated TRA concentrations in lymph nodes, kidneys, and spleen, indicating rhIL-7-hyFc's affinity for these organs. The study also simulated the positions of 14C labeling in rhIL-7-hyFc, identifying specific residues in the fragment of rhIL-7 portion, and provided the explanation of distinct analytes targeted by each method. Combining ELISA and AMS provided advantages by offering sensitivity and specificity for quantification as well as enabling the identification of analyte forms. The integrated use of ELISA and AMS offers valuable insights for the development and optimization of ABT.

A randomized phase II study of atezolizumab (atezo) plus recombinant human IL-7 (CYT107) in patients with locally advanced or metastatic urothelial carcinoma.

628 Background: Atezolizumab (atezo) is an anti-PD-L1 antibody that was approved for use in patients with mUC following platinum-containing regimens. IL-7 (CYT107) is a homeostatic cytokine that supports the proliferation and persistence of T cells. We hypothesized that combining CYT107 with atezo would improve responses in mUC patients. Methods: To test this, we performed a randomized trial (NCT03513952) comparing the combination of CYT107/atezo to atezo alone in patients with mUC previously treated with a platinum regimen. Key eligibility criteria included ECOG PS 0-2, measurable disease (RECIST 1.1), and no prior systemic immunotherapy. A safety run-in using CYT107/atezo was performed (n=7), followed by randomization 1:1 to atezo 1200 mg IV q3wks +/- CYT107 10 ug/kg IM qwk X 4. The primary endpoint was objective response rate (ORR), with secondary endpoints of clinical benefit rate, PFS, DOR, OS, and safety, with a number of exploratory correlative analyses. Results: A total of 47 patients were enrolled. Patient demographics between arms were well-balanced. No dose limiting toxicities (DLTs) were seen. Overall, the combination of CYT107/atezo was well tolerated compared to the atezo monotherapy arm, with overall grade 3-4 (G3-4) adverse events (AEs) occurring in 46.2% (12/26) and 63.2% (12/19) of patients, respectively. Rates of treatment-related events were: Any (80.8% vs 73.7%), G1-2 (65.4% vs 36.8%), and G3-4 (15.4% vs 36.8%) in CYT107/atezo vs monotherapy arms, respectively. Treatment-related immune-mediated AEs of any grade occurred in 50% (13/26) of patients in combination arm vs 68.4% (13/19) in monotherapy arm. 0% vs 17.6% of patients on the combination vs monotherapy arm discontinued therapy due to toxicity, respectively. ORR was 26.3% vs 23.8% in the combination vs monotherapy arm (p=0.43), respectively. Complete responses (CR) were seen in 10.5% (2/19) and 4.8% (1/21), and partial responses seen in 15.8% (3/19) and 19% (4/21) of patients in the combination vs monotherapy arms, respectively. There were no significant differences in clinical benefit rate (36.8% vs 42.9%), PFS (2.3 vs 2.2 mos), or OS (9.1 vs 10.4 mos). Rapid expansion of T cells was observed (~1.7-fold by day 8 following first dosing) in the CYT107/atezo arm only. Expansion peaked earlier for CD4s (~2-fold, day 22) and later for CD8s (~2.1-fold, day 29) and was maintained above baseline through C6D01. Detailed T cell subset pharmacodynamic data will be presented. Conclusions: This is the first randomized trial of atezo +/- IL-7 (CYT107) in mUC. During the trial, the FDA approval for atezo in mUC was withdrawn, which limited enrollment. However, our results show that the addition of CYT107 to atezo is safe/tolerable, with comparable toxicity profile and efficacy to monotherapy. Clinical trial information: NCT03513952 .

Effectiveness and economic evaluation of rhTPO and rhIL-11 in the treatment of cancer therapy induced thrombocytopenia based on real-world research.

Objective: Based on real-world research, we aimed to evaluate the effectiveness and economy of recombinant human thrombopoietin (rhTPO) and recombinant human interleukin 11 (rhIL-11) in the treatment of cancer therapy induced thrombocytopenia (CTIT). Methods: We retrospectively collected clinical data of patients with CTIT who were treated with rhTPO or rhIL-11 in a single cancer hospital from January 2020 to December 2021. Propensity score matching (PSM) was applied to eliminate confounding factors. The measurements of effectiveness analysis were the platelet compliance rate, days of medication, days of compliance, highest platelet count after medication, platelet count elevation before and after medication, and the lowest platelet count after next-cycle cancer therapy. The economic evaluation was performed according to the results of the effectiveness evaluation. At the same time, patients were stratified according to type of tumor and grade of thrombocytopenia for subgroup analysis. Results: A total of 262 patients were collected and 174 patients were enrolled after PSM, 87 in the rhTPO group and 87 in the rhIL-11 group. In all patients, there were no significant differences in the platelet compliance rate, mean days of medication, median days of compliance, median highest platelet count after medication, and the median platelet count elevation before and after medication between the two groups (p > 0.05), but the median lowest platelet count after next-cycle cancer therapy in the rhTPO group was lower than that in the rhIL-11 group (p = 0.014). The subgroup analysis showed that the rhTPO group had longer mean days of medication than the rhIL-11 group in patients with hematological malignancies (p = 0.042), and a lower median lowest platelet count after next-cycle cancer therapy in patients with grade I/II thrombocytopenia than rhIL-11 group (p = 0.022), with no significant difference in other outcome indicators (p > 0.05). As there was no statistically significant difference in platelet compliance rate between the two groups, the cost-minimization analysis showed that the rhIL-11 group had lower treatment costs than the rhTPO group. Conclusion: RhTPO and rhIL-11 showed similar effectiveness in the treatment of CTIT, but rhIL-11 was more advantageous in economic cost.

Phase II study evaluating the efficacy of PDS0301 in combination with hepatic artery infusion pump (HAIP) and systemic therapy for patients with metastatic colorectal cancer or intrahepatic cholangiocarcinoma.

TPS586 Background: Treatment of advanced liver tumors continues to pose significant challenges. Despite advances in immunotherapies, including immune checkpoint blockade, responses in colorectal liver metastases and biliary tract cancers remain suboptimal. The lack of robust clinical efficacy is likely myriad, including immunosuppression by the tumor microenvironment and poor susceptibility of these tumors to immune infiltration and surveillance. Interleukin-12 (IL-12) is a pro-inflammatory cytokine with extensive anti-tumor properties, but therapeutic development of recombinant human IL-12 (rhIL-12) was halted due to significant systemic toxicities. PDS0301 (formerly M9241) is a novel human monoclonal antibody (NHS76) fused to two IL-12 heterodimers. The NHS76 antibody specifically targets histone/DNA complexes in regions of cellular necrosis resulting in accumulation within tumors. Importantly, recent Phase I trials have shown PDS0301 monotherapy to be well tolerated. We hypothesize that synchronization of PDS0301 administration with tumor cell death induced by locoregional and systemic chemotherapies will demonstrate increased efficacy over standard of care therapy. Methods: This is a single center, non-randomized Phase II study to determine the safety and efficacy of PDS0301 in combination with floxuridine (FUDR) administered by hepatic artery infusion pump (HAIP) and systemic chemotherapies in patients with either unresectable metastatic colorectal cancer (mCRC) or intrahepatic cholangiocarcinoma (ICC). Eligibility criteria include histologically or cytologically confirmed colorectal adenocarcinoma metastatic to the liver (Cohort 1) or unresectable intrahepatic cholangiocarcinoma with no evidence of extrahepatic metastases (Cohort 2). Patients will receive HAIP-administered (FUDR) plus PDS0301 at a starting dose of 12mcg/kg in 28-day cycles. Beginning in cycle 2, systemic chemotherapy with FOLFOX (Leucovorin, 5-Fluorouracil [5-FU], and Oxaliplatin) or FOLFIRI (Leucovorin, 5-FU and Irinotecan) for mCRC or GemOx (Gemcitabine and Oxaliplatin) for ICC will be introduced. Patients will be evaluated for response at eight-week intervals. The primary endpoint is overall response rates to PDS0301 and HAIP/systemic combination therapy. Secondary objectives include hepatic progression-free survival (PFS), extra-hepatic PFS, overall survival, and safety. Scientific objectives include determination of microenvironment alterations through pre-and post-treatment biopsies as well as evaluation of peripheral immune subsets and cytokines. To date, we have enrolled 8 of 23 patients in Cohort 1. Clinical trial information: NCT05286814 .

A randomized controlled pilot trial of anakinra and pioglitazone for protein metabolism in patients on maintenance haemodialysis.

Chronic inflammation and insulin resistance are highly prevalent in patients on maintenance haemodialysis (MHD) and are strongly associated with protein energy wasting. We conducted a pilot, randomized, placebo-controlled trial of recombinant human interleukin-1 receptor antagonist (IL-1ra) and pioglitazone to explore the safety, feasibility and efficacy for insulin-mediated protein metabolism in patients undergoing MHD. Twenty-four patients were randomized to receive IL-1ra, pioglitazone or placebo for 12weeks. Changes in serum inflammatory markers and insulin-mediated protein synthesis, breakdown and net balance in the whole-body and skeletal muscle compartments were assessed using hyperinsulinaemic-hyperaminoacidemic clamp technique at baseline and Week 12. Among 24 patients, median (interquartile range) age was 51 (40, 61), 79% were African American and 21% had diabetes mellitus. All patients initiated on intervention completed the study, and no serious adverse events were observed. There was a statistically significant decrease in serum high-sensitivity C-reactive protein in the pioglitazone group compared with placebo, but not in the IL-1ra group. No significant differences in the changes of whole-body or skeletal muscle protein synthesis, breakdown and net balance were found between the groups. In this pilot study, there were no statistically significant effects of 12weeks of IL-1ra or pioglitazone on protein metabolism in patients on MHD. gov registration: NCT02278562.

IL-1 Family Blockade in Cytokine Storm Syndromes.

Interleukin-1 is a prototypic proinflammatory cytokine that is elevated in cytokine storm syndromes (CSSs), such as secondary hemophagocytic lymphohistiocytosis (sHLH) and macrophage activation syndrome (MAS). IL-1 has many pleotropic and redundant roles in both innate and adaptive immune responses. Blockade of IL-1 with recombinant human interleukin-1 receptor antagonist has shown efficacy in treating CSS. Recently, an IL-1 family member, IL-18, has been demonstrated to be contributory to CSS in autoinflammatory conditions, such as in inflammasomopathies (e.g., NLRC4 mutations). Anecdotally, recombinant IL-18 binding protein can be of benefit in treating IL-18-driven CSS. Lastly, another IL-1 family member, IL-33, has been postulated to contribute to CSS in an animal model of disease. Targeting of IL-1 and related cytokines holds promise in treating a variety of CSS.

Fc-fused IL-7 provides broad antiviral effects against respiratory virus infections through IL-17A-producing pulmonary innate-like T cells

Repeated pandemics caused by the influenza virus and severe acute respiratory syndrome coronavirus (SARS-CoV) have resulted in serious problems in global public health, emphasizing the need for broad-spectrum antiviral therapeutics against respiratory virus infections. Here, we show the protective effects of long-acting recombinant human interleukin-7 fused with hybrid Fc (rhIL-7-hyFc) against major respiratory viruses, including influenza virus, SARS-CoV-2, and respiratory syncytial virus. Administration of rhIL-7-hyFc in a therapeutic or prophylactic regimen induces substantial antiviral effects. During an influenza A virus (IAV) infection, rhIL-7-hyFc treatment increases pulmonary Tcells composed of blood-derived interferon γ (IFNγ)+ conventional Tcells and locally expanded IL-17A+ innate-like Tcells. Single-cell RNA transcriptomics reveals that rhIL-7-hyFc upregulates antiviral genes in pulmonary Tcells and induces clonal expansion of type 17 innate-like Tcells. rhIL-7-hyFc-mediated disease prevention is dependent on IL-17A in both IAV- and SARS-CoV-2-infected mice. Collectively, we suggest that rhIL-7-hyFc can be used as a broadly active therapeutic for future respiratory virus pandemic.

ВЛИЯНИЕ РОНКОЛЕЙКИНА НА МОРФОМЕТРИЧЕСКИЕ И ГЕМАТОЛОГИЧЕСКИЕ ПОКАЗАТЕЛИ И ФАГОЦИТАРНУЮ И ГЕМАТОЛОГИЧЕСКИЕ ПОКАЗАТЕЛИ И ФАГОЦИТАРНУЮ

Cultivated hydrobionts under intensive aquaculture conditions are exposed to stress factors associated with artificial habitats, increased planting density, periodic fishing, etc. At the same time, they experience a decrease in resistance and resilience and an increase in morbidity. A good solution to this problem is the use of immunomodulators. This article presents the results of a study of the effect on fish of the immunomodulator Roncoleukin, which is a dosage form of recombinant human interleukin-2 (IL-2) isolated and purified from yeast cells (Saccharomyces cerevisiae). The subject of the study was the three-year-old Arctic char (Salvelinus alpinus). The evaluation was based on morphometric, hematological (erythro- and leukogram) and cytochemical (lysosomal cation test) indicators. The coefficient of variation of the size and weight parameters of the treated fish was low compared to the con- trol group. This indicates uniform growth of fish fed Roncoleukin, which is a great advantage in fish farming and provides more efficient use of feed. Blood for analysis was taken from the tail vein of the fish in vivo. The results showed a positive effect of the drug on the activation of erythropoiesis and leukopoiesis. There was a significant increase in the proportion of mature segmented neutrophils (the main blood microphages belonging to the non-specific link of cellular immunity) in the leukocyte formula due to a decrease in lymphocytes (specific immunity). An increase in the content of nonenzymatic lysosomal cationic proteins (defensins) in blood neutrophils can indicate a high level of cellular protection of microphages (neutrophils). The results of the study showed a positive effect of the drug Roncoleukin, which can be recommended for use in the ferming of Arctic char.

Generation of human ILC3 from allogeneic and autologous CD34+ hematopoietic progenitors toward adoptive transfer

Type 3 innate lymphoid cells (ILC3) are important in tissue homeostasis. In the gut, ILC3 repair damaged epithelium and suppress inflammation. In allogeneic hematopoietic cell transplantation (HCT), ILC3 protect against graft-versus-host disease (GvHD), most likely by restoring tissue damage and preventing inflammation. We hypothesize that supplementing HCT grafts with interleukin-22 (IL-22)-producing ILC3 may prevent acute GvHD. We therefore explored ex vivo generation of human IL-22-producing ILC3 from hematopoietic stem and progenitor cells (HSPC) obtained from adult, neonatal and fetal sources. We established a stroma-free system culturing human cord blood-derived CD34+ HSPC with successive cytokine mixes for 5 weeks. We analyzed the presence of phenotypically defined ILC, their viability, proliferation and IL-22 production (after stimulation) by flow cytometry and enzyme-linked immunosorbent assay (ELISA). We found that the addition of recombinant human IL-15 and the enhancer of zeste homolog 1/2 inhibitor UNC1999 promoted ILC3 generation. Similar results were demonstrated when UNC1999 was added to CD34+ HSPC derived from healthy adult granulocyte colony-stimulating factor mobilized peripheral blood and bone marrow, but not fetal liver. UNC1999 did not negatively impact IL-22 production in any of the HSPC sources. Finally, we observed that autologous HSPC mobilized from the blood of adults with hematological malignancies also developed into ILC3, albeit with a significantly lower capacity. Together, we developed a stroma-free protocol to generate large quantities of IL-22-producing ILC3 from healthy adult human HSPC that can be applied for adoptive transfer to prevent GvHD after allogeneic HCT.

Abstract A074: Discovery of WTX-330, a clinical stage conditionally activated IL-12 INDUKINETM therapeutic with potent antitumor activity in murine syngeneic tumor models resistant to checkpoint blockade

Abstract Background: IL-12 is a pleotropic inflammatory cytokine with broad stimulatory effects on immune cells and robust antitumor activity in syngeneic murine tumor models, making it an attractive target for cancer immunotherapy. Unfortunately, systemic administration of recombinant human IL-12 causes severe toxicity in patients. With the goal of improving the therapeutic index for IL-12 therapy, we have engineered an IL-12 prodrug referred to as an INDUKINETM molecule that is dosed systemically but designed to be selectively activated in tumors. Methods: Mice bearing MC38, CT26, B16F10, and EMT-6 syngeneic tumors were treated with surrogate mWTX-330 (a chimeric IL-12 containing INDUKINETM molecule), and tumor growth and body weight were monitored over time. Tumor tissues were harvested at various timepoints and analyzed by flow cytometry, NanoString GeoMx Digital Spatial Profiling (DSP), and high-plex immunofluorescence to characterize the mechanisms associated with response. Results: mWTX-330 is comprised of a half-life extension domain and an inactivation domain tethered to chimeric IL-12 by tumor protease-sensitive linkers. These linkers were chosen for their selective processing by a majority of human tumors in vitro as well as mouse tumors in vitro and in vivo. The linkers have been shown in preclinical studies to remain stable in normal human tissues including serum. Systemic administration of mWTX-330 in mice was well tolerated, resulted in robust antitumor immunity in multiple tumor models, including those resistant to checkpoint blockade, and preferentially activated tumor-infiltrating immune cells versus peripheral cells. Antitumor activity was dependent on in vivo processing of the protease cleavable linkers and required CD8+ T cells for full efficacy, although NK and CD4+ T cells also contributed to tumor growth inhibition. Within the tumor, mWTX-330 increased the frequency of cross-presenting dendritic cells (DCs), activated natural killer (NK) cells, skewed conventional CD4+ T cells toward a T helper 1 (TH1) phenotype, drove regulatory T cells (Treg) fragility, and increased the frequency of polyfunctional CD8+ T cells. mWTX-330 treatment also increased the clonality of tumor-infiltrating T cells by expanding underrepresented T-cell receptor (TCR) clones, drove CD8+ T and NK cells towards increased mitochondrial respiration and fitness, and decreased the frequency of TOX+ exhausted CD8+ T cells within the tumor. Conclusion: Based on the strong biological rational and preclinical studies of surrogate mWTX-330, we created WTX-330, a fully human IL-12 INDUKINETM molecule that is stable in human serum and is reliably and selectively processed by human tumor samples in vitro. A first-in-human clinical trial to evaluate the safety profile, pharmacokinetics, and preliminary antitumor activity of WTX-330 in patients with relapsed/refractory advanced or metastatic solid tumors or non-Hodgkin lymphoma is now underway (NCT05678998). Citation Format: Christopher J Nirschl, Heather R Brodkin, Sameer S Chopra, Connor J Dwyer, Daniel J Hicklin, Randi Isaacs, Nesreen Ismail, Cynthia Seidel-Dugan, Zoe Steuert, Jenna M Sullivan, William M Winston, Andres Salmeron. Discovery of WTX-330, a clinical stage conditionally activated IL-12 INDUKINETM therapeutic with potent antitumor activity in murine syngeneic tumor models resistant to checkpoint blockade [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr A074.