Intratumoral injection reduces toxicity and antibody-mediated neutralization of immunocytokine in a mouse melanoma model

BackgroundSome patients with cancer treated with anticancer monoclonal antibodies (mAbs) develop antidrug antibodies (ADAs) that recognize and bind the therapeutic antibody. This response may neutralize the therapeutic mAb, interfere with mAb effector function or cause toxicities. We investigated the potential influence of ADA to modify the tumor-binding capability of a tumor-reactive ‘immunocytokine’ (IC), namely, a fusion protein (hu14.18-IL2) consisting of a humanized, tumor-reactive, anti-GD2 mAb genetically linked to interleukin 2. We characterize the role of treatment delivery of IC (intravenous vs intratumoral) on the impact of ADA on therapeutic outcome following IC treatments in an established antimelanoma (MEL) regimen involving radiotherapy (RT) +IC.MethodsC57BL/6 mice were injected with human IgG or the hu14.18-IL2 IC to develop a mouse anti-human antibody (MAHA) response (MAHA+). In vitro assays were performed to assess ADA binding to IC using sera from MAHA+ and MAHA− mice. In vivo experiments assessed the levels of IC bound to tumor in MAHA+ and MAHA− mice, and the influence of IC route of delivery on its ability to bind to B78 (GD2+) MEL tumors.ResultsMAHA is inducible in C57BL/6 mice. In vitro assays show that MAHA is capable of inhibiting the binding of IC to GD2 antigen on B78 cells, resulting in impaired ADCC mediated by IC. When B78-bearing mice are injected intravenously with IC, less IC binds to B78-MEL tumors in MAHA+ mice than in MAHA− mice. In contrast, when IC is injected intratumorally in tumor-bearing mice, the presence of MAHA does not detectibly impact IC binding to the tumor. Combination therapy with RT+IT-IC showed improved tumor regression compared with RT alone in MAHA+ mice. If given intratumorally, IC could be safely readministered in tumor-bearing MAHA+ mice, while intravenous injections of IC in MAHA+ mice caused severe toxicity. Histamine levels were elevated in MAHA+ mice compared with MAHA− mice after reintroduction of IC.ConclusionsIntratumoral injection may be a means of overcoming ADA neutralization of therapeutic activity of tumor-reactive mAbs or ICs and may reduce systemic toxicity, which could have significant translational relevance.

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A bispecific antibody agonist of the IL-2 heterodimeric receptor preferentially promotes in vivo expansion of CD8 and NK cells

Scientific Reports ◽

10.1038/s41598-021-90096-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Katherine E. Harris ◽

Kyle J. Lorentsen ◽

Harbani K. Malik-Chaudhry ◽

Kaitlyn Loughlin ◽

Harish Medlari Basappa ◽

...

Keyword(s):

T Cells ◽

Nk Cells ◽

Bispecific Antibody ◽

T Regulatory Cells ◽

Tumor Regression ◽

Interleukin 2 ◽

In Vivo Studies ◽

Preferential Binding

AbstractThe use of recombinant interleukin-2 (IL-2) as a therapeutic protein has been limited by significant toxicities despite its demonstrated ability to induce durable tumor-regression in cancer patients. The adverse events and limited efficacy of IL-2 treatment are due to the preferential binding of IL-2 to cells that express the high-affinity, trimeric receptor, IL-2Rαβγ such as endothelial cells and T-regulatory cells, respectively. Here, we describe a novel bispecific heavy-chain only antibody which binds to and activates signaling through the heterodimeric IL-2Rβγ receptor complex that is expressed on resting T-cells and NK cells. By avoiding binding to IL-2Rα, this molecule circumvents the preferential T-reg activation of native IL-2, while maintaining the robust stimulatory effects on T-cells and NK-cells in vitro. In vivo studies in both mice and cynomolgus monkeys confirm the molecule’s in vivo biological activity, extended pharmacodynamics due to the Fc portion of the molecule, and enhanced safety profile. Together, these results demonstrate that the bispecific antibody is a safe and effective IL-2R agonist that harnesses the benefits of the IL-2 signaling pathway as a potential anti-cancer therapy.

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Visualizing the Potential Impairment of Polymyxin B to Central Nervous System Through MR Susceptibility-Weighted Imaging

Frontiers in Pharmacology ◽

10.3389/fphar.2021.784864 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ni Zhang ◽

Lichong Zhu ◽

Qiuhong Ouyang ◽

Saisai Yue ◽

Yichun Huang ◽

...

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Polymyxin B ◽

Susceptibility Weighted Imaging ◽

Gram Negative Bacteria ◽

Severe Toxicity ◽

Gram Negative ◽

The Impact

Polymyxin B (PMB) exert bactericidal effects on the cell wall of Gram-negative bacteria, leading to changes in the permeability of the cytoplasmic membrane and resulting in cell death, which is sensitive to the multi-resistant Gram-negative bacteria. However, the severe toxicity and adverse side effects largely hamper the clinical application of PMB. Although the molecular pathology of PMB neurotoxicity has been adequately studied at the cellular and molecular level. However, the impact of PMB on the physiological states of central nervous system in vivo may be quite different from that in vitro, which need to be further studied. Therefore, in the current study, the biocompatible ultra-uniform Fe3O4 nanoparticles were employed for noninvasively in vivo visualizing the potential impairment of PMB to the central nervous system. Systematic studies clearly reveal that the prepared Fe3O4 nanoparticles can serve as an appropriate magnetic resonance contrast agent with high transverse relaxivity and outstanding biosafety, which thus enables the following in vivo susceptibility-weighted imaging (SWI) studies on the PMB-treated mice models. As a result, it is first found that the blood-brain barrier (BBB) of mice may be impaired by successive PMB administration, displaying by the discrete punctate SWI signals distributed asymmetrically across brain regions in brain parenchyma. This result may pave a noninvasive approach for in-depth studies of PMB medication strategy, monitoring the BBB changes during PMB treatment, and even assessing the risk after PMB successive medication in multidrug-resistant Gram-negative bacterial infected patients from the perspective of medical imaging.

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IL-2 administration increases CD4+CD25hi Foxp3+ regulatory T cells in cancer patients

Blood ◽

10.1182/blood-2005-06-2399 ◽

2006 ◽

Vol 107 (6) ◽

pp. 2409-2414 ◽

Cited By ~ 433

Author(s):

Mojgan Ahmadzadeh ◽

Steven A. Rosenberg

Keyword(s):

T Cells ◽

Regulatory T Cells ◽

Interleukin 2 ◽

Selective Inhibition ◽

High Dose ◽

Protein Levels ◽

And Function ◽

The Impact

Abstract Interleukin-2 (IL-2) is historically known as a T-cell growth factor. Accumulating evidence from knockout mice suggests that IL-2 is crucial for the homeostasis and function of CD4+CD25+ regulatory T cells in vivo. However, the impact of administered IL-2 in an immune intact host has not been studied in rodents or humans. Here, we studied the impact of IL-2 administration on the frequency and function of human CD4+CD25hi T cells in immune intact patients with melanoma or renal cancer. We found that the frequency of CD4+CD25hi T cells was significantly increased after IL-2 treatment, and these cells expressed phenotypic markers associated with regulatory T cells. In addition, both transcript and protein levels of Foxp3, a transcription factor exclusively expressed on regulatory T cells, were consistently increased in CD4 T cells following IL-2 treatment. Functional analysis of the increased number of CD4+CD25hi T cells revealed that this population exhibited potent suppressive activity in vitro. Collectively, our results demonstrate that administration of high-dose IL-2 increased the frequency of circulating CD4+CD25hi Foxp3+ regulatory T cells. Our findings suggest that selective inhibition of IL-2-mediated enhancement of regulatory T cells may improve the therapeutic effectiveness of IL-2 administration. (Blood. 2006;107:2409-2414)

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CD38-Targeted Immunochemotherapy Of Multiple Myeloma: Preclinical Evidence For Its Combinatorial Use In Lenalidomide and Bortezomib Refractory/Intolerant MM Patients

Blood ◽

10.1182/blood.v122.21.277.277 ◽

2013 ◽

Vol 122 (21) ◽

pp. 277-277 ◽

Cited By ~ 3

Author(s):

Inger S. Nijhof ◽

Willy A. Noort ◽

Jeroen Lammerts van Bueren ◽

Berris van Kessel ◽

Joost M. Bakker ◽

...

Keyword(s):

Multiple Myeloma ◽

Research Funding ◽

Plasma Cells ◽

Cell Lysis ◽

In Vitro Assays ◽

Human Antibody ◽

Myeloma Cells ◽

Clinical Phase

Abstract Multiple myeloma (MM) remains an incurable malignancy of clonal plasma cells. Although the new generation of immunomodulatory agents, such as lenalidomide (LEN), and the potent proteasome inhibitor bortezomib (BORT) have significantly improved the overall survival of MM patients, all chemotherapy strategies are eventually hampered by the development of drug-resistance. The outcome of patients who are refractory to thalidomide, lenalidomide (LEN) and bortezomib (BORT) is very poor. Set out with the idea that targeted immunotherapy with human antibodies may offer new perspectives for MM patients, we have recently developed daratumumab (DARA), a CD38 human antibody with broad-spectrum killing activity, mainly via ADCC (antibody dependent cellular cytotoxicity) and CDC (complement dependent cytotoxicity). In our previous preclinical studies and in current clinical phase I/II trials, DARA induces marked anti-MM activity. Based on these encouraging results, we now explored the potential activity of DARA for patients who are refractory to LEN- and/or BORT. In a recently developed human-mouse hybrid model that allows the in vivo engraftment and outgrowth of patient-derived primary myeloma cells in immune deficient Rag2-/-gc-/- mice, single dose DARA treatment appeared to effectively inhibit the malignant expansion of primary MM cells derived from a LEN- and BORT-refractory patient, indicating the potential efficacy of DARA even in LEN/BORT refractory patients. To substantiate the conclusions of these in vivo data, we conducted in vitro assays, in which full BM-MNCs from LEN (n=11) and LEN/BORT (n=8) refractory patients were treated with DARA alone or the combination of DARA with LEN or BORT to induce MM cell lysis. As expected, LEN alone induced no or little lysis of MM cells in the LEN-refractory patients and also BORT was not able to induce any lysis in the BORT-refractory patients. On the contrary, DARA induced substantial levels of MM cell lysis in all LEN and LEN/BORT-refractory patients. This lysis was significantly enhanced by combination with LEN or BORT. The combination of DARA and BORT improved MM lysis by additive mechanisms. However, LEN improved DARA-mediated lysis of MM cells in a synergistic manner through the activation of effector cells involved in DARA-mediated ADCC. In conclusion, our results demonstrate that DARA is also effective against multiple myeloma cells derived from LEN- and BORT-refractory patients. Especially LEN seems to improve responses in a synergistic manner. Our results provide a rationale for clinical evaluation of DARA in combination with LEN to achieve more effective results in LEN- and BORT-refractory patients. Disclosures: Lammerts van Bueren: Genmab: Employment. Bakker:Genmab: Employment. Parren:Genmab: Employment. van de Donk:Celgene: Research Funding. Lokhorst:Genmab A/S: Consultancy, Research Funding; Celgene: Honoraria; Johnson-Cilag: Honoraria; Mudipharma: Honoraria.

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Growth Inhibition of Murine Colonic Adenocarcinoma by Tumor Immune but not by IL-2-Activated or Alloactivated Lymphocytes

Tumori Journal ◽

10.1177/030089168707300101 ◽

1987 ◽

Vol 73 (1) ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Monica Rodolfo ◽

Giorgio Parmiani

Keyword(s):

Tumor Growth ◽

Tumor Cells ◽

Interleukin 2 ◽

In Vitro Assays ◽

Growing Cell ◽

Spleen Lymphocytes ◽

Antigenic Profile ◽

Colonic Adenocarcinomas

The antigenic profile of C-26 and C-51 BALB/c colonic adenocarcinomas was examined by in vivo and in vitro assays. Mice immunized with irradiated C-26 or C-51 tumor cells from freshly excised tumor nodules or from in vitro-growing cell lines were able to reject a challenge of both tumors. Spleen lymphocytes of immune but not of normal mice were effective in cross-inhibiting tumor growth in vivo in a Winn assay. Tissue-associated antigens common to C-26 and C-51 and to their metastases but not to other syngeneic neoplasms were detected in vitro by cytotoxic T lymphocytes obtained after 5 days of a secondary culture of immune lymphocytes and irradiated tumor cells. Activated lymphocytes were obtained by exposure of spleen cells to interleukin 2 or by allostimulation. Such lymphocytes, although cytotoxic in vitro on C-26 and C-51 carcinomas, were unable to significantly reduce in vivo tumor growth in the Winn assay.

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Interleukin-2 transcription is regulated in vivo at the level of coordinated binding of both constitutive and regulated factors.

Molecular and Cellular Biology ◽

10.1128/mcb.14.3.2159 ◽

1994 ◽

Vol 14 (3) ◽

pp. 2159-2169 ◽

Cited By ~ 89

Author(s):

P A Garrity ◽

D Chen ◽

E V Rothenberg ◽

B J Wold

Keyword(s):

T Cells ◽

Dna Binding ◽

Cyclosporin A ◽

Interleukin 2 ◽

Cell Types ◽

Regulatory Elements ◽

In Vitro Assays ◽

Nuclear Extracts

Interleukin-2 (IL-2) transcription is developmentally restricted to T cells and physiologically dependent on specific stimuli such as antigen recognition. Prior studies have shown that this stringent two-tiered regulation is mediated through a transcriptional promoter/enhancer DNA segment which is composed of diverse recognition elements. Factors binding to some of these elements are present constitutively in many cell types, while others are signal dependent, T cell specific, or both. This raises several questions about the molecular mechanism by which IL-2 expression is regulated. Is the developmental commitment of T cells reflected molecularly by stable interaction between available factors and the IL-2 enhancer prior to signal-dependent induction? At which level, factor binding to DNA or factor activity once bound, are individual regulatory elements within the native enhancer regulated? By what mechanism is developmental and physiological specificity enforced, given the participation of many relatively nonspecific elements? To answer these questions, we have used in vivo footprinting to determine and compare patterns of protein-DNA interactions at the native IL-2 locus in cell environments, including EL4 T-lymphoma cells and 32D clone 5 premast cells, which express differing subsets of IL-2 DNA-binding factors. We also used the immunosuppressant cyclosporin A as a pharmacological agent to further dissect the roles played by cyclosporin A-sensitive factors in the assembly and maintenance of protein-DNA complexes. Occupancy of all site types was observed exclusively in T cells and then only upon excitation of signal transduction pathways. This was true even though partially overlapping subsets of IL-2-binding activities were shown to be present in 32D clone 5 premast cells. This observation was especially striking in 32D cells because, upon signal stimulation, they mobilized a substantial set of IL-2 DNA-binding activities, as measured by in vitro assays using nuclear extracts. We conclude that binding activities of all classes fail to stably occupy their cognate sites in IL-2, except following activation of T cells, and that specificity of IL-2 transcription is enforced at the level of chromosomal occupancy, which appears to be an all-or-nothing phenomenon.

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A Short S-Equol Exposure Has a Long-Term Inhibitory Effect on Adipogenesis in Mouse 3T3-L1 Cells

Applied Sciences ◽

10.3390/app11209657 ◽

2021 ◽

Vol 11 (20) ◽

pp. 9657

Author(s):

Gilberto Mandujano-Lázaro ◽

Carlos Galaviz-Hernández ◽

César A. Reyes-López ◽

Julio C. Almanza-Pérez ◽

Abraham Giacoman-Martínez ◽

...

Keyword(s):

Weight Control ◽

Inhibitory Effect ◽

New Drugs ◽

Metabolic Effects ◽

In Vitro Assays ◽

Differentiation Protocol ◽

Body Weight Control ◽

The Impact

In the search for new drugs against obesity, the chronic disease that threatens human health worldwide, several works have focused on the study of estrogen homologs because of the role of estrogen receptors (ERs) in adipocyte growth. The isoflavone equol, an ERβ agonist, has shown beneficial metabolic effects in in vivo and in vitro assays; however, additional studies are required to better characterize its potential for body weight control. Here, we showed that the treatment of 3T3-L1 cells with 10 μM of S-equol for the first three days of the adipocyte differentiation protocol was able to prevent cells becoming semi-rounded and having a lipid droplet formation until the seventh day of culture; moreover, lipid accumulation was reduced by about 50%. Congruently, S-equol induced a reduction in mRNA expression of the adipogenic markers C/EBPα and PPARγ, and adipokines secretion, mainly Adiponectin, Leptin, Resistin, and MCP-1, while the release of PAI-1 was augmented. Moreover, it also reduced the expression of ERα and attenuated the subexpression of ERβ associated with adipogenesis. Altogether, our data suggested that S-equol binding to ERβ affects the transcriptional program that regulates adipogenesis and alters adipocyte functions. Future efforts will focus on studying the impact of S-equol on ER signaling pathways.

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The structure of an alternate form of complement C3 that displays costimulatory growth factor activity for B lymphocytes.

Journal of Experimental Medicine ◽

10.1084/jem.180.6.2079 ◽

1994 ◽

Vol 180 (6) ◽

pp. 2079-2088 ◽

Cited By ~ 9

Author(s):

Y Cahen-Kramer ◽

I L Mårtensson ◽

F Melchers

Keyword(s):

B Cells ◽

Interleukin 2 ◽

Immunoglobulin M ◽

Complement C3 ◽

In Vitro Assays ◽

Leader Peptide ◽

Coding Region ◽

Reading Frame

In this study, the structure of a novel 1.9-kb transcript coding for complement component 3 (C3) is described. This alternate C3 is identical to the 3' end of the C3 message beginning at position 3300 of the C3 cDNA. Its transcription appears to be driven by an alternate promoter located within intron 8 of the C3 gene. This alternate C3 message contains an open reading frame that may encode a 536-amino acid-long protein identical to the 3' part of the C3 alpha chain. The resulting protein contains the complement receptor CR2 binding site. The suggested 5' end of coding region of the alternate C3 includes information for a potential hydrophobic leader peptide that would allow secretion of the protein. In vitro assays with macrophage-depleted mouse splenic B cells indicate that an activity is secreted from cell lines transfected with the alternate C3 cDNA. Together with Sepharose-bound immunoglobulin M-specific monoclonal antibodies and interleukin 2, it costimulates the proliferation of B cells. Implications for possible in vivo functions are discussed.

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PTEN expression in endothelial cells is down-regulated by uPAR to promote angiogenesis

Thrombosis and Haemostasis ◽

10.1160/th15-01-0016 ◽

2015 ◽

Vol 114 (08) ◽

pp. 379-389 ◽

Cited By ~ 10

Author(s):

Matthias Unseld ◽

Anastasia Chilla ◽

Clemens Pausz ◽

Rula Mawas ◽

Johannes Breuss ◽

...

Keyword(s):

Endothelial Cells ◽

In Vitro Assays ◽

Soluble Form ◽

Dependent Manner ◽

Drug Interference ◽

Protein Levels ◽

Novel Target ◽

The Impact

SummaryThe tumour suppressor phosphatase and tensin homologue (PTEN), mutated or lost in many human cancers, is a major regulator of angiogenesis. However, the cellular mechanism of PTEN regulation in endothelial cells so far remains elusive. Here, we characterise the urokinase receptor (uPAR, CD87) and its tumour-derived soluble form, suPAR, as a key molecule of regulating PTEN in endothelial cells. We observed uPAR-deficient endothelial cells to express enhanced PTEN mRNA- and protein levels. Consistently, uPAR expression in endogenous negative uPAR cells, down-regulated PTEN and activated the PI3K/Akt pathway. Additionally, we found that integrin adhesion receptors act as trans-membrane signaling partners for uPAR to repress PTEN transcription in a NF-κB-dependent manner. Functional in vitro assays with endothelial cells, derived from uPAR-deficient and PTEN heterozygous crossbred mice, demonstrated the impact of uPAR- dependent PTEN regulation on cell motility and survival. In an in vivo murine angiogenesis model uPAR-deficient PTEN heterozygous animals increased the impaired angiogenic phenotype of uPAR knockout mice and were able to reverse the high invasive potential of PTEN heterozygots. Our data provide first evidence that endogenous as well as exogenous soluble uPAR down-regulated PTEN in endothelial cells to support angiogenesis. The uPAR-induced PTEN regulation might represent a novel target for drug interference, and may lead to the development of new therapeutic strategies in anti-angiogenic treatment.

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