CD3 Antibodies Research Articles

How Co-Stimulatory/Inhibitory Molecules Vary Across Immune Cell Subtypes in the Severity of Systemic Lupus Erythematosus Compared to Controls

Background: Co-stimulatory and co-inhibitory molecules are critical to T cell responses and involved in the pathogenesis of systemic lupus erythematosus (SLE). This study aimed to comprehensively analyze the surface expression of these molecules in various phenotypic immune cells, comparing the differences between various levels of the severity in SLE and control groups. Methods: Peripheral blood mononuclear cells (PBMCs) were isolated using Ficoll-Paque from blood samples of severe SLE patients (treatment with immunosuppressants), mild SLE patients (excluding those with persistent proteinuria or thrombocytopenia), and healthy controls (n = 10 each). PBMCs were stimulated for 48 h. The cells were stained with anti-CD3, CD4, CD28, PD-1, and CTLA-4 antibodies and analyzed by flow cytometry. Differences between groups were assessed using the Kruskal–Wallis test and Mann–Whitney U-test, with median values and statistical significance (p < 0.05) reported. Results: The results showed that CD28 expression was significantly higher in SLE patients compared to controls, with the highest levels in mild SLE. However, CD3+ CD28+ and CD4+ CD28+ cells were more prevalent in controls (p = 0.032 and 0.017, respectively). Mild SLE patients exhibited the highest CTLA-4 expression, with significant differences from severe SLE and controls (p = 0.030 and 0.037, respectively). PD-1 expression was lowest in severe SLE but highest in mild SLE within CD3+ CD4+ cells (p = 0.001). After 48 h of activation, CD4+ CTLA4+ and CD3+ CTLA4+ expression levels were significantly higher in controls compared to SLE groups. Conclusions: Our study highlighted that the expression of CD28, CTLA-4, and PD-1 in lymphocytes and specific T cell subsets was various according the severity of SLE in patients, underscoring their roles in disease pathogenesis.

Abstract PR-11: Fc-optimized agonistic CD40 antibody induces tumor rejection and systemic antitumor immunity - From the bench to the bedside and back

Abstract PR-11: Fc-optimized agonistic CD40 antibody induces tumor rejection and systemic antitumor immunity - From the bench to the bedside and back

P53 ABNORMAL ENDOMETRIAL CANCERS – ANALYSIS OF PD-1 CO-EXPRESSION BY CD4 HELPER AND CD8 CYTOTOXIC T-CELL SUBTYPES IN THE TUMOR MICROENVIRONMENT

Abstract Introduction/Objective Endometrial cancer is classified into four molecular subtypes of which the p53 abnormal variant is biologically aggressive. Programmed cell death protein 1 (PD-1) is a cell surface receptor and a vital inhibitor of the immune response. Programmed death ligand 1 (PD-L1) is a trans-membrane co-inhibitory factor of the immune response. PD-1 / PDL-1 interaction inhibits the activation and survival of T cells and decreases cytokine secretion. Some cancer cells express PD-L1, which then bind to PD-1 expressed on tumor specific T cells, and escape destruction by the T cells. The CD4/CD8 T cell immune response in the p53 abnormal variant has not been adequately evaluated with respect to the PD-1/PD-L1 pathway. Understanding this immune microenvironment is important to assess the potential use of anti-PD-1 targeted tumor therapy. Methods/Case Report Twenty cases of p53 abnormal endometrial cancers were obtained. All cases were PDL-1 +ve by immunohistochemistry. Two dual stains were performed - PD-1/CD4 and PD-1/CD8 antibodies. Six high-power fields (40x objective) with the greatest concentration of lymphocytes were counted. The total number of CD4 or CD8-only cells was recorded for each of the two stained slides for each case. The total number of PD- 1/CD4 and PD-1/CD8 positive cells were counted and recorded. The results were tabulated, and a paired t-test statistical analysis was performed to compare the total number of CD4 and CD8 cells and the percentage of PD-1/CD4 cells with the percentage of PD-1/CD8 positive cells. Results (if a Case Study enter NA) A statistically significant increase in the number of CD8 (Mean = 383) compared to CD4 cells (Mean = 317) was seen in the tumor microenvironment (p-value=0.0023). Evaluating PD-1 expression, the converse was true, and the percentage of PD-1/CD4 cells (Mean = 13.035%) was increased compared to the percentage of PD-1/CD8 cells (Mean = 9.205%), achieving statistical significance (p-value=0.0116). Conclusion The statistically significant increase in CD8 cells in the tumor and its stroma suggests that a robust cytotoxic response is being mounted to this high-risk molecular variant. The concurrent increase in CD4/PD-1 positive lymphocytes provides an appropriate microenvironment for the use of anti-PD-1 immunotherapy, since blockade of PD-1 on CD4 helper T cells may augment the tumor ablative cytotoxic properties of the CD8 positive lymphocytes. This includes reinvigoration of exhausted CD8+ T cells. Anti-PD-1 may also prevent the inhibition of PD-1 positive CD8 cells.

Immunoexpression of CD34, CD68 and CD3 in Cadmium-Induced Liver Damage and Protective Effectiveness of Bee Bread (Perga)

Cadmium (Cd) is one of the potent environmental toxicants that causes oxidative stress in many organs of the body, including the liver. Perga (bee bread) is used for apitherapeutic purposes due to its medicinal properties. This study was conducted to investigate the effectiveness of perga on endothelial damage and inflammatory cell activation in the liver as a result of exposure to Cd. For this purpose, 32 male Wistar rats (8 rats/group) were randomly divided into 4 groups, as the control, perga (0.5 g/kg of perga), Cd (5 mg/kg of CdCl2), and Cd + perga (0.5 g/kg of perga + 5 mg/kg of CdCl2) groups. Daily intragastric Cd and/or perga was administered for 4 weeks. At the end of the study, the rats were euthanized and liver tissue sections were taken and stained with hematoxylin-eosin and Masson’s Trichrome. Immunohistochemically, the reactivity of the liver sinusoidal endothelium was determined using CD34, the reactivity of the Kupffer cells was determined using CD68, and the levels of T-lymphocyte cells were determined using CD3 antibodies. Exposure to Cd caused significant histological changes in the liver. Immunohistochemically, exposure to Cd caused an increase in the expressions of CD34, CD68, and CD3. On the other hand, the cotreatment of Cd and perga caused partial improvement in some histopathological changes. Compared to the Cd group, there was a decrease in CD34 and CD68 positivity in the Cd + perga group, while no significant difference was detected in the number of CD3-positive cells between the groups. The results revealed that the histopathological changes and inflammation in the rat liver could partially improve with perga supplementation.

The impact of cryopreservation on cytokine secretion and polyfunctionality in human PBMCs: a comparative study.

Human peripheral blood mononuclear cells (hPBMCs) are widely used in fundamental research and clinical applications as studying their responses to in vitro activation is an effective way to uncover functional alterations and disease associated phenotypes. However, the availability of samples in large numbers at a specific time and location remains challenging, hence they often might preferably be collected and cryopreserved for later analysis. While the effect of cryopreservation on viability and cell surface expression is well established, changes in activity and cytokine secretion still lead to conflicting results as it is often measured in bulk or within the cells. Here, we used our platform for dynamic single-cell multiplexed cytokine secretion measurement and compared it to a traditional intracellular cytokine staining to quantify the effect of cryopreservation on cytokine secretion and expression of individual hPBMCs. Following stimulation with LPS or anti-CD3/CD28 antibodies for up to 36 or 72 h incubation, we observed distinct alterations in cytokine responses due to cryopreservation when comparing to fresh samples, but also remarkable consistencies for some cytokines and parameters. In short, the frequencies of cytokine-secreting cells in cryopreserved samples were lower for IL-6 (LPS), IL1-β (CD3/CD28) and IFN-γ (CD3/CD28), while the frequency and dynamics of IL-8 secretion were strongly impacted in all cases. We observed a large disconnect between cytokine expression and secretion for TNF-α, where the expression dramatically increased after cryopreservation, but actual secretion was, in comparison, remarkably stable. The polyfunctionality of single cells was altered by cryopreservation in specific co-secreting populations led by the effects on IL-6 or IL-8 secretion. Among immune cells, cryopreservation seemed to affect lymphocytes and monocytes differently as effects appeared early on in lymphocytes while generally observed in later time points in monocytes. Together, this study offers an in-depth quantitative insight into the biological behavior of immune cells in response to cryopreservation and stimulation, further providing some insights into conflicting results in theliterature as well as guidelines for researchers planning to assess cytokine-secreting from frozen hPBMCs in immunological research or clinical applications.

B-343 Development of CD40 and HER2 Bispecific Antibodies for Enhanced Efficacy against HER2-Positive Tumors

Abstract Background CD40, a member of the tumor necrosis factor superfamily, is primarily expressed on antigen-presenting cells. This receptor plays a crucial role in facilitating the interaction between dendritic cells, activating antigen-specific T cells. Agonist antibodies targeting the CD40 receptor have the potential to mimic the natural CD40 ligand, fostering dendritic cell maturation and stimulating immunity against “cold” tumors. Although this approach has shown promise in preclinical studies, translating it to clinical success has been challenging. Only modest anti-tumor activity was observed in cancer patients, and none of the developed CD40 monoclonal antibodies (mAbs) progressed beyond early clinical trials, highlighting a need for improved anti-tumor efficacy. Methods In this study, we successfully developed an anti-human CD40 agonist rabbit monoclonal antibody using Yurogen's proprietary SMAB(TM) platform. The most potent CD40 mAb clone was combined with trastuzumab (an anti-HER2 mAb) to create a therapeutic bispecific antibody. Our goal is to leverage immune cell activation through HER2-targeted cancer therapy to achieve enhanced anti-tumor activity. Dozens of diverse CD40xHER2 bispecific antibody designs (both symmetry and asymmetry) were explored, with careful evaluation of expression yield, purity, and binding profiles for each target respectively. Results A few bispecific antibody designs demonstrated robust binding to both HER2 and CD40 antigen proteins, as well as receptor-expressing cell lines. Notably, two developed bispecific antibodies exhibited potent killing of HER2-positive cancer cells with the assistance of innate immune cells. Conclusions In sum, this study provides novel insights into designing bispecific antibodies against HER2 and CD40, offering a promising avenue for advancing cancer immunotherapy.

Comparative evaluation of the therapeutic effect of combined schemes for therapy and rehabilitation in acute respiratory infections with the inclusion of immunocorrective and sedative agents in children from 6 months to 6 years on the background of stress disorders in the conditions of war in Ukraine

Background. Acute respiratory infections (ARIs) are one of the most common groups of diseases in the practice of pediatricians. Stressful factors affect the immune system, reducing its effectiveness and leading to direct impact on the nervous system and the occurrence of its disorders: sleep changes, the development of a post-traumatic stress disorder, a decrease in the quality of life, especially during the last years in wartime conditions in Ukraine. The latter requires improving the implementation of combined therapeutic approaches to increase a short- and long-term effect on the health of the youngest children. Aim of the study: to increase the effectiveness of treatment and rehabilitation of children from the youngest age group (6 months to 6 years) with ARIs against the background of stress disorders of the war in Ukraine by using comprehensive schemes with the inclusion of immunocorrective (the drug with immunocorrective properties contained a complex of ultra-low-dose dilutions of gamma interferon antibodies, histamine antibodies, CD4 antibodies) and sedative (the drug with sedative properties contained antibodies to the brain-specific protein S100) agents. Material and methods. The study involved 119 children aged 6 months to 6 years who had ≥ 5 episodes of ARIs (55 %) during the previous year and permanently lived in almost the entire territory of Ukraine (Kyiv, Kharkiv, Lviv, Dnipro, Zaporizhzhia, Odesa, Kropyvnytskyi, Vinnytsia, Kryvyi Rih, Zhytomyr, Cherkasy, Poltava, Sumy, Berdychiv, Romny, Bila Tserkva). The study was carried out as part of the program for outpatient observation of children with various manifestations of ARIs against the background of stress damage to the nervous system who took drugs with immunocorrective properties (scheme (1)) alone and in combination with a sedative agent (scheme (1+2)). The drug with immunocorrective pro­perties contained a complex of ultra-low-dose dilutions of gamma interferon antibodies, histamine antibodies, CD4 antibodies, and the drug with sedative properties — antibodies to the brain-specific protein S100. The observation period was October-December 2023. Statistical processing of the results was carried out using GraphPad Prism 9.0 Software for Windows (USA, San Diego, CA). Results. The combined therapeutic approach of the scheme (1+2) showed a significantly better effect on fever, duration of low fever, sore throat, runny nose, bronchitis symptoms, manifestations of respiratory infection, assessed by the Wisconsin Questionnaire, as well as stress, sleep disorders, and changes in the quality of life on the 5th day of treatment and after 1 month of observation. The comparative evaluation of scheme (1) and scheme (1+2) showed a significant diffe­rence in favor of the effectiveness of the latter, which is ensured by its additional sedative and anti-anxiety action, resulting in a direct positive effect on stress-induced disturbances of the nervous system and an indirect — on the immune response, which in general increases the effectiveness of solving the problem of ARI therapy in children aged 6 months to 6 years, who for 2.5 years were constantly in psycho-traumatizing and socially oppressed conditions of the war in Ukraine. The analysis of satisfaction with the treatment effect according to the international IMOS scale during the observation period showed positive results and a high level of evaluation by both parents and doctors. Conclusions. The use of a combination of reme­dies with immunocorrective and sedative effects showed their high mutual enhancing effectiveness in the treatment and rehabilitation of children aged 6 months to 6 years, suffering from ARIs, and in the correction of stress disorders caused by the war in Ukraine.

Implications of CD154 and Its Receptors in the Pathogenesis and Treatment of Systemic Lupus Erythematosus.

CD154, also known as CD40 ligand, is a costimulatory molecule involved in humoral and adaptive immune responses upon pairing with its classical receptor, CD40. The CD154/CD40 dyad is a key participant in the pathogenesis of many autoimmune diseases, including systemic lupus erythematosus (SLE). In SLE, the major cells at play, T and B lymphocytes, are shown to overexpress CD154 and CD40, respectively. Subsequently, these cells and other CD40-positive cells engage in numerous effector functions contributing to SLE development. With the recent identification of additional receptors for CD154, all belonging to the integrin family, the role of CD154 in SLE is more complex and calls for deeper investigation into its biological significance. Many therapeutic strategies directed against the CD154/CD40 couple have been deployed for the treatment of SLE and proved efficient in animal models and human studies. However, the incidence of thromboembolic complications in patients treated with these anti-CD154/CD40 antibodies halted their further clinical assessments and called for another class of therapies targeting these molecules. Second-generation antibodies directed against CD154 or CD40 are showing promising results in the advanced stages of clinical testing. Our review presents a thorough description of CD154 and its receptors, CD40 and the integrin family members in SLE pathogenesis. All these elements of the CD154 system represent important therapeutic targets for the treatment of SLE.

Abstract A056: Pancreatic ductal adenocarcinoma derived cancer-associated fibroblasts suppress tumor infiltrating lymphocytes in the tumor microenvironment

Abstract Patients with pancreatic ductal adenocarcinoma (PDAC) have a poor prognosis due to late presentation of disease and frequent resistance to therapy. Immunotherapy regimens have uniformly failed in PDAC, which has long been considered an immunologically cold tumor. It is believed that immunotherapy has been unsuccessful in PDAC due to its dense, fibrotic, and immunosuppressive microenvironment. Cancer-associated fibrosis may account for up to 90% of the PDAC microenvironment, thus further study of this immunosuppressive component is urgently needed. Methods Human PDAC surgical specimens were procured, sectioned, and allocated for histology, flow cytometry, tumor-infiltrating lymphocyte (TIL) expansion, and fibroblast culture. For histology, tumor slices were saved in 10% formalin and wax embedded. Histological PDAC slides were stained against fibroblasts markers alpha smooth muscle actin, fibroblast activation protein; and T-cell markers CD3, CD69, CD25, FOXP3. First, tumor sections were digested using mechanical and chemical techniques. For flow cytometry, digested tumor cells were stained with fluorescent conjugated antibodies targeting CD45, CD3, CD4, CD8, CD25, CD69, PD-1 and ICAM. For TIL isolation and expansion, resultant single-cells were bead-isolated for CD3 positive cells, cultured and expanded with 2000 IU interleukin-2 and 1.5 mg/mL anti-CD3/CD28 antibodies. For fibroblast culture, fibroblasts were bead isolated and sub-cultured in RPMI supplemented with FGF. TILs were co-cultured with patient-derived fibroblasts/fibroblast media with the PD-L1 inhibitor Atezolizumab. TILs were then analyzed by flowcytometry, and media from co-culture was analyzed via ELISA for gamma interferon release. Results TILs isolated from PDAC (N=5) co-cultured with patient-matched fibroblasts or media were phenotypically compared using flow cytometry and measure for gamma interferon release. Interestingly, TILs co-cultured with fibroblasts or fibroblast media showed improved expansion over peripheral blood derived control T-cells, but both groups showed highly impaired gamma interferon release. Co-cultured TILs had high levels of PD-1 and low levels of CD69, compared to control TILs, indicating a suppressed phenotype. TILs co-cultured with fibroblasts and Atezolizumab resulted in significantly increased CD69 expression and gamma interferon release (P>0.05), indicating an activated phenotype. Histological PDAC slides showed abundant T-cell infiltrates with minimal CD69 expression. CD25+ T-cells were identified throughout fibrotic areas of the TME. Conclusion Here, we challenge the long-held belief that PDAC is immunologically cold as our tumor cross-sections (N=5) were rich in T-cells. More importantly, our results show that tumor-derived fibroblasts appear to play a role in suppression of TIL function, which is partially reversible with immunomodulatory techniques (e.g., anti-PDL1therapy). Our results warrant further investigation into targeting CAFs in PDAC microenvironment to improve patient response to immunotherapy. Citation Format: Charles Bailey, Hannah Mcdonald, Anna Reagan, Michael Cavnar, Mautin Barry-Hundeyin, Prakash Pandalai, Joseph Kim. Pancreatic ductal adenocarcinoma derived cancer-associated fibroblasts suppress tumor infiltrating lymphocytes in the tumor microenvironment [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A056.

Abstract PR-10: Phase 1b study of maintenance soluble beta-glucan (Odetiglucan) in combination with a CD40 agonistic monoclonal antibody (CDX-1140) in patients with metastatic pancreatic adenocarcinoma that had not progressed on first-line chemotherapy

Abstract Background: Metastatic pancreatic ductal adenocarcinoma (mPDAC) has a dismal 5-year overall survival (OS) rate of 3%. Current standard of care provides only modest anti-cancer impact. Preclinical models show that combinations of myeloid agonists can induce strong anti-tumor activity in PDAC tumors resistant to immunotherapy, including immune checkpoint blockade (anti-CTLA4, anti-PD1). This study combines odetiglucan, a beta glucan pathogen-associated molecular pattern (PAMP), with CDX-1140, a fully human Ig2K agonistic monoclonal CD40 antibody, in the maintenance setting after cytotoxic chemotherapy induction. Preliminary findings are presented as the study was closed early for financial reasons. Methods: Patients with mPDAC who had not progressed after 4-8 months of 1L chemotherapy were enrolled and received weekly odetiglucan (4 mg/kg) plus every 3-week dosing of CDX-1140 (1.5 mg/kg). The primary endpoints were safety, MTD and RP2D, with secondary endpoints including DOR, PFS, ORR, and OS. Tissue and blood samples were collected at baseline and during treatment to evaluate immune pharmacodynamic responses. Results: A total of 5 patients received treatment on study including 4 patients who were efficacy evaluable and 1 patient who withdrew due to adverse event (arthralgia) after beginning treatment. Treatment-related emergent adverse events were seen in all patients with most common AEs including grade 1-2 arthralgia, chills, and fatigue. Grade 3 AEs included arthralgia (n=1), fatigue (n=1), and leukopenia (n=2). The ORR included 1 PR, 1 SD, and 2 PD. Two patients remained on treatment for >100 days. The pharmacodynamic profile was consistent with the mode of action of odetiglucan and CDX-1140, including a reduction in peripheral Dectin-1 expressing monocytes and transient decreases in peripheral B cells. Patients with disease control (PR or SD, n=2) compared to patients with progression (PD, n=2) showed expansion of peripheral Ki67+ CD8+ T cells following treatment. Analysis of a paired tumor biopsy from 1 patient with PD confirmed penetration of odetiglucan into a liver metastasis with expansion of CD11b+ macrophages and a reduction of cytokeratin+ tumor content, but without significant changes in T cell infiltration. Conclusions: The combination of odetiglucan and CDX-1140 was feasible and safe when administered as maintenance therapy in patients with mPDAC whose disease had not progressed on 1L chemotherapy. Treatment produced encouraging activity with changes in immunological correlates associated with disease control. These early results support further investigation combining odetiglucan with a CD40 agonist in mPDAC. Citation Format: Mark H O'Hara, Max Wattenberg, Ignacio Garrido-Laguna, Eileen M O'Reilly, Michael Yellin, Tibor Keler, Michele Gargano, Nick Niles, Jeremy Drees, Nandita Bose, Gregory L Beatty. Phase 1b study of maintenance soluble beta-glucan (Odetiglucan) in combination with a CD40 agonistic monoclonal antibody (CDX-1140) in patients with metastatic pancreatic adenocarcinoma that had not progressed on first-line chemotherapy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr PR-10.

Abstract B061: Phase 1b study of maintenance soluble beta-glucan (Odetiglucan) in combination with a CD40 agonistic monoclonal antibody (CDX-1140) in patients with metastatic pancreatic adenocarcinoma that had not progressed on first-line chemotherapy

Abstract Background: Metastatic pancreatic ductal adenocarcinoma (mPDAC) has a dismal 5-year overall survival (OS) rate of 3%. Current standard of care provides only modest anti-cancer impact. Preclinical models show that combinations of myeloid agonists can induce strong anti- tumor activity in PDAC tumors resistant to immunotherapy, including immune checkpoint blockade (anti-CTLA4, anti-PD1). This study combines odetiglucan, a beta glucan pathogen- associated molecular pattern (PAMP), with CDX-1140, a fully human Ig2K agonistic monoclonal CD40 antibody, in the maintenance setting after cytotoxic chemotherapy induction. Preliminary findings are presented as the study was closed early for financial reasons. Methods: Patients with mPDAC who had not progressed after 4-8 months of 1L chemotherapy were enrolled and received weekly odetiglucan (4 mg/kg) plus every 3-week dosing of CDX-1140 (1.5 mg/kg). The primary endpoints were safety, MTD and RP2D, with secondary endpoints including DOR, PFS, ORR, and OS. Tissue and blood samples were collected at baseline and during treatment to evaluate immune pharmacodynamic responses. Results: A total of 5 patients received treatment on study including 4 patients who were efficacy evaluable and 1 patient who withdrew due to adverse event (arthralgia) after beginning treatment. Treatment-related emergent adverse events were seen in all patients with most common AEs including grade 1-2 arthralgia, chills, and fatigue. Grade 3 AEs included arthralgia (n=1), fatigue (n=1), and leukopenia (n=2). The ORR included 1 PR, 1 SD, and 2 PD. Two patients remained on treatment for >100 days. The pharmacodynamic profile was consistent with the mode of action of odetiglucan and CDX-1140, including a reduction in peripheral Dectin-1 expressing monocytes and transient decreases in peripheral B cells. Patients with disease control (PR or SD, n=2) compared to patients with progression (PD, n=2) showed expansion of peripheral Ki67+ CD8+ T cells following treatment. Analysis of a paired tumor biopsy from 1 patient with PD confirmed penetration of odetiglucan into a liver metastasis with expansion of CD11b+ macrophages and a reduction of cytokeratin+ tumor content, but without significant changes in T cell infiltration. Conclusions: The combination of odetiglucan and CDX-1140 was feasible and safe when administered as maintenance therapy in patients with mPDAC whose disease had not progressed on 1L chemotherapy. Treatment produced encouraging activity with changes in immunological correlates associated with disease control. These early results support further investigation combining odetiglucan with a CD40 agonist in mPDAC. Citation Format: Mark H O'Hara, Max Wattenberg, Ignacio Garrido-Laguna, Eileen M O'Reilly, Michael Yellin, Tibor Keler, Michele Gargano, Nick Niles, Jeremy Drees, Nandita Bose, Gregory L Beatty. Phase 1b study of maintenance soluble beta-glucan (Odetiglucan) in combination with a CD40 agonistic monoclonal antibody (CDX-1140) in patients with metastatic pancreatic adenocarcinoma that had not progressed on first-line chemotherapy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B061.

Photothermal therapy co-localized with CD137 agonism improves survival in an SM1 melanoma model without hepatotoxicity.

Aim: We investigate combining Prussian Blue nanoparticles (PBNPs), as photothermal therapy (PTT) agents, with agonistic CD137 antibodies (αCD137) on a single nanoparticle platform to deliver non-toxic, anti-tumor efficacy in SM1 murine melanoma.Methods: We electrostatically coated PBNPs with αCD137 (αCD137-PBNPs) and quantified their physicochemical characteristics, photothermal and co-stimulatory capabilities. Next, we tested the efficacy and hepatotoxicity of PTT using αCD137-PBNPs (αCD137-PBNP-PTT) in SM1 tumor-bearing mice.Results: The αCD137-PBNPs retained both the photothermal and agonistic properties of the PBNPs and αCD137, respectively. In vivo, SM1 tumor-bearing mice treated with αCD137-PBNP-PTT exhibited a significantly higher survival rate (50%) without hepatotoxicity, compared with control treatments.Conclusion: These data suggest the potential utility of co-localizing PBNP-PTT with αCD137-based agonism as a novel combination nanomedicine.

The Skin Histopathology of Pro- and Parabiotics in a Mouse Model of Atopic Dermatitis.

As it has been revealed that the activation of human immune cells through the activity of intestinal microorganisms such as pro- and prebiotics plays a vital role, controlling the proliferation of beneficial bacteria and suppressing harmful bacteria in the intestine has become essential. The importance of probiotics, especially for skin health and the immune system, has led to the emergence of products in various forms, including probiotics, prebiotics, and parabiotics. In particular, atopic dermatitis (AD) produces hypersensitive immunosuppressive substances by promoting the differentiation and activity of immune regulatory T cells. As a result, it has been in the Th1 and Th2 immune balance through a mechanism that suppresses skin inflammation or allergic immune responses caused by bacteria. Furthermore, an immune mechanism has recently emerged that simultaneously controls the expression of IL-17 produced by Th17. Therefore, the anti-atopic effect was investigated by administering doses of anti-atopic candidate substances (Lactobacilus sakei CVL-001, Lactobacilus casei MCL, and Lactobacilus sakei CVL-001 Lactobacilus casei MCL mixed at a ratio of 4:3) in an atopy model using 2,4-dinitrochlorobenzene and observing symptom changes for 2 weeks to confirm the effect of pro-, para-, and mixed biotics on AD. First, the body weight and feed intake of the experimental animals were investigated, and total IgG and IgM were confirmed through blood biochemical tests. Afterward, histopathological staining was performed using H&E staining, Toluidine blue staining, Filaggrin staining, and CD8 antibody staining. In the treatment group, the hyperproliferation of the epidermal layer, the inflammatory cell infiltration of the dermal layer, the expression of CD8, the expression of filaggrin, and the secretion of mast cells were confirmed to be significantly reduced. Lastly, small intestine villi were observed through a scanning microscope, and scoring evaluation was performed through skin damage. Through these results, it was confirmed that AD was reduced when treated with pro-, para-, and mixed biotics containing probiotics and parabiotics.

Human/mouse CD137 agonist, JNU-0921, effectively shrinks tumors through enhancing the cytotoxicity of CD8+ T cells in cis and in trans.

Agonistic antibodies against CD137 have been demonstrated to completely regress established tumors through activating T cell immunity. Unfortunately, current CD137 antibodies failed to benefit patients with cancer. Moreover, their antitumor mechanisms in vivo remain to be determined. Here, we report the development of a small molecular CD137 agonist, JNU-0921. JNU-0921 effectively activates both human and mouse CD137 through direct binding their extracellular domains to induce oligomerization and signaling and effectively shrinks tumors in vivo. Mechanistically, JNU-0921 enhances effector and memory function of cytotoxic CD8+ T cells (CTLs) and alleviates their exhaustion. JNU-0921 also skews polarization of helper T cells toward T helper 1 type and enhances their activity to boost CTL function. Meanwhile, JNU-0921 attenuates the inhibitory function of regulatory T cells on CTLs. Our current work shows that JNU-0921 shrinks tumors by enhancing the cytotoxicity of CTLs in cis and in trans and sheds light on strategy for developing CD137 small molecular agonists.

Testicular tumors in commercial boars with infertility: A gross, histologic, and immunohistochemical study.

Tumors in boars are uncommon, and testicular tumors even rarer. This study describes the pathological and immunohistochemical characteristics of a case series of testicular tumors in commercial boars with fertility problems. Tumors were detected in 19 of 333 animals (19/333, 5.9%). Macroscopically, tumors were observed in 13 (13/19, 68%) boars, while 6 cases (6/19, 32%) were only detected by microscopic examination. Testicular enlargement was observed in 1 boar, while in the others, tumors were only observed after removal of the scrotal skin or after sectioning of the testis. Histologically, tumors were classified as seminomas (16/19, 84%), mixed germ cell-stromal tumors (2/19, 11%), and B-cell lymphoma (1/19, 5%). Seminomas had 3 different growth patterns: intratubular (6/16, 38%), diffuse (4/16, 25%), and intratubular/diffuse (6/16, 38%). All tumors that were not evident on macroscopic examination were intratubular seminomas. Intratesticular metastases were observed in 2 cases and extratesticular metastases, located in the pampiniform plexus, were observed in 1 case. In 1 seminoma, the rete testis was also involved. By immunohistochemistry, all intratubular seminomas were negative for c-kit, cytokeratin, and vimentin. In diffuse seminomas, c-kit and cytokeratin were also negative, while vimentin showed granular or perinuclear cytoplasmic labeling in some areas. PAX-5 and CD-3 antibodies classified the lymphoma as a B-cell lymphoma. This study suggests that testicular tumors in boars may be more common than previously reported, especially when microscopic examination is performed. It also shows that testicular tumors in pigs are predominantly seminomas.

Efficient generation of human immune system rats using human CD34+ cells

Human immune system (HIS) mice generated using human CD34+ hematopoietic stem cells serve as a pivotal model for the invivo evaluation of immunotherapies for humans. Yet, HIS mice possess certain limitations. Rats, due to their size and comprehensive immune system, hold promise for translational experiments. Here, we describe an efficacious method for long-term immune humanization, through intrahepatic injection of hCD34+ cells in newborn immunodeficient rats expressing human SIRPα. In contrast to HIS mice and similar to humans, HIS rats showed in blood a predominance of Tcells, followed by B cells. Immune humanization was also high in central and secondary lymphoid organs. HIS rats treated with the anti-human CD3 antibody were depleted of human Tcells, and human cytokines were detected in sera. We describe for the first time a method to efficiently generate HIS rats. HIS rats have the potential to be a useful model for translational immunology.

Good manufacturing practice-grade generation of CD19 and CD123-specific CAR-T cells using piggyBac transposon and allogeneic feeder cells in patients diagnosed with B-cell non-Hodgkin lymphoma and acute myeloid leukemia.

The non-viral production of CAR-T cells through electroporation of transposon DNA plasmids is an alternative approach to lentiviral/retroviral methods. This method is particularly suitable for early-phase clinical trials involving novel types of CAR-T cells. The primary disadvantage of non-viral methods is the lower production efficiency compared to viral-based methods, which becomes a limiting factor for CAR-T production, especially in chemotherapy-pretreated lymphopenic patients. We describe a good manufacturing practice (GMP)-compliant protocol for producing CD19 and CD123-specific CAR-T cells based on the electroporation of transposon vectors. The lymphocytes were purified from the blood of patients undergoing chemotherapy for B-NHL or AML and were electroporated with piggyBac transposon encoding CAR19 or CAR123, respectively. Electroporated cells were then polyclonally activated by anti-CD3/CD28 antibodies and a combination of cytokines (IL-4, IL-7, IL-21). The expansion was carried out in the presence of irradiated allogeneic blood-derived mononuclear cells (i.e., the feeder) for up to 21 days. Expansion in the presence of the feeder enhanced CAR-T production yield (4.5-fold in CAR19 and 9.3-fold in CAR123). Detailed flow-cytometric analysis revealed the persistence of early-memory CAR-T cells and a low vector-copy number after production in the presence of the feeder, with no negative impact on the cytotoxicity of feeder-produced CAR19 and CAR123 T cells. Furthermore, large-scale manufacturing of CAR19 carried out under GMP conditions using PBMCs obtained from B-NHL patients (starting number=200x10e6 cells) enabled the production of >50x10e6 CAR19 in 7 out of 8 cases in the presence of the feeder while only in 2 out of 8 cases without the feeder. The described approach enables GMP-compatible production of sufficient numbers of CAR19 and CAR123 T cells for clinical application and provides the basis for non-viral manufacturing of novel experimental CAR-T cells that can be tested in early-phase clinical trials. This manufacturing approach can complement and advance novel experimental immunotherapeutic strategies against human hematologic malignancies.

Enhanced interleukin-16-CD4 signaling in CD3 T cell mediates neuropathic pain via activating astrocytes in female mice

Immune cells and interleukins play a crucial role in female-specific pain signaling. Interleukin 16 (IL-16) is a cytokine primarily associated with CD4+ T cell function. While previous studies have demonstrated the important role of spinal CD4+ T cells in neuropathic pain, the specific contribution of IL-16 to neuropathic pain remains unclear. In this study, by using a spinal nerve ligation (SNL)-induced neuropathic pain mice model, we found that SNL induced an increase in IL-16 mRNA levels, which persisted for a longer duration in female mice compared to male mice. Immunofluorescence analysis further confirmed enhanced IL-16- and CD4-positive signals in the spinal dorsal horn following SNL surgery in female mice. Knockdown of spinal IL-16 by siRNA or inhibition of CD4 by FGF22-IN-1, a CD4 inhibitor, attenuated established mechanical and thermal pain hypersensitivity induced by SNL. Furthermore, female mice injected with IL-16 intrathecally exhibited significant spontaneous pain, mechanical and thermal hyperalgesia, all of which could be alleviated by FGF22-IN-1 or a CD3 antibody. Additionally, IL-16 induced astrocyte activation but not microglial activation in the spinal dorsal horn of female mice. Meanwhile, astrocyte activation could be suppressed by the CD3 antibody. These results provide compelling evidence that IL-16 promotes astrocyte activation via CD4 on CD3+ T cells, which is critical for maintaining neuropathic pain in female mice.

CD305 participates in abnormal activation of memory CD4+ T cells in patients with RA and attenuates collagen-induced arthritis

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that mainly affects the joints. Studies have shown that memory CD4+ T cells play an important role in the pathogenesis of RA. This study investigated the expression and function of CD305 on human memory CD4+ T cells and the effects of CD305 activating antibody on collagen-induced arthritis. The results showed that CD305 expression was significantly decreased on circulating memory CD4+ T cells from patients with RA and its mean fluorescence intensity (MFI) was negatively correlated with DAS28. Moreover, CD305 inhibited the activation of memory CD4+ T cells by down-regulating CD69 and CD25 and the production of IFN-γ, IL-4, and IL-17A induced by anti-CD3/CD28 antibodies. In addition, activation of CD305 inhibited the severity of disease in collagen-induced arthritis. In summary, CD305 reduction may mediate the excessive activation of memory CD4+ T cells and participate in the development of RA. It can be used as a predictive marker of disease activity and has potential medicinal value in the treatment of RA.

Enhancing the activation of T cells through anti-CD3/CD28 magnetic beads by adjusting the antibody ratio.

The utilization of anti-CD3/CD28 magnetic beads for T cell expansion in vitro has been investigated for adoptive cell transfer therapy. However, the impact of the CD3/CD28 antibody ratio on T cell differentiation and function remains incompletely elucidated. This study seeks to address this knowledge gap. To begin with, CD3 antibodies with a relatively low avidity for Jurkat cells (Kd = 13.55 nM) and CD28 antibodies with a relatively high avidity (Kd = 5.79 nM) were prepared. Afterwards, anti-CD3/CD28 antibodies with different mass ratios were attached to magnetic beads to examine the impacts of different antibody ratios on T cell capture, and proliferation. The research demonstrated that the most significant expansion of T cells was stimulated by the anti-CD3/CD28 magnetic beads with a mass ratio of 2:1 for CD3 antibodies and CD28 antibodies. Moreover, CD25 and PD1 expression of expanded T cells increased and then decreased, with lower CD25 and PD1 expression in the later stages of expansion indicating that T cells were not depleted. These T cells, which are massively expanded in vitro and have excellent expansion potential, can be infused back into the patient to treat tumor patients. This study shows that altering the ratio of anti-CD3/CD28 antibodies can control the strength of T cell stimulation, thereby leading to the improvement of T cell activation. This discovery can be utilized as a guide for the creation of other T cell stimulation approaches, which is beneficial for the further development of tumor immunotherapy technology.