Delivery Of Granulocyte-macrophage Colony-stimulating Factor Research Articles

A First-in-Human Phase I Clinical Study with MVX-ONCO-1, a Personalized Active Immunotherapy, in Patients with Advanced Solid Tumors.

This first-in-human phase I study introduces a groundbreaking approach to personalized cancer immunotherapy, addressing limitations of traditional strategies. By combining autologous irradiated tumor cells as a source of patient-specific antigens and utilizing encapsulated cell technology for localized, sustained delivery of granulocyte-macrophage colony-stimulating factor as an adjuvant, the study shows a very good safety and feasibility profile. This innovative approach holds the promise of addressing tumor heterogeneity by taking advantage of each patient's antigenic repertoire.

Current opportunities and prospectives of immunotropic therapy in chronic generalized periodontitis

Impairment of immunological reactivity in inflammatory periodontal diseases is well proven. To perform immunomodulatory treatment in domestic dental practice, various medications are used, including natural, chemically modified, recombinant, genetically engineered and synthetic substances, which differ in their effects upon innate and adaptive immune systems. Complex preparations of natural cytokines as well as genetically engineered preparations of IL-1, IL-2, growth factors, IFNα, IFNβ, IFNγ are applied in clinical settings. Clinical implementation of interferon and interferon inducers in combined therapy of generalized periodontitis is shown to increase resistance to viral components of the oral microbiota. Growth factors (platelet growth factor, fibroblast growth factor, endothelial growth factor, etc.) are successfully used for tissue regeneration in periodontics and maxillofacial surgery. Experimental studies have shown that local administration of toll-like receptor-9 and CD40 ligand may reduce periodontal ligature inflammation and bone loss in mice by inducing B-cell proliferation and increasing IL-10 mRNA expression. Promising results in development of new biologically active drugs are obtained with nanotechnology approaches, i.e., production of composite materials of metal nanoparticles with polymers, growth factors, and local application of these products. General limitations of all these growth factors include extremely short periods of biological activity, and adjusted duration of local effective concentrations. Therefore, it is important to develop a drug delivery system using appropriate scaffolding elements thus allowing local effects of the drug for a certain period of time. In experimental models, alginate hydrogels performed well upon local delivery of granulocyte-macrophage colony-stimulating factor and stromal lymphopoietin of the thymus. A new immunomodulatory strategy for alveolar bone regeneration targets macrophages. A biologically functionalized injectable microsphere of heparin-modified gelatin nanofibers that mimic the architecture of the natural bone extracellular matrix, and provide an osteoconductive microenvironment for bone cells includes IL-4, which has heparin-binding domains. These medications represent a component of a comprehensive treatment schedule, and should be evaluated for immune status before and after therapy. Thus, recent advances in studies of innate and acquired immune responses in inflammatory diseases and, in particular, in periodontal disorders, allows us to develop new approaches and methods of treatment in order to improve efficiency of complex therapy in the inflammatory periodontal diseases.

Abstract 2672: Localized delivery of granulocyte-macrophage colony-stimulating factor to alleviate tumor hypoxia and immunosuppression in breast cancer

Abstract The purpose of this study is to investigate localized delivery of recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) as a potential therapeutic modality in breast cancer to alleviate tumor hypoxia and immunosuppression. A therapeutic that has the potential to target and reverse these factors of the tumor microenvironment (TME) would aid in reducing tumor aggressiveness, immune escape, metastasis, and importantly, could potentially be administered as a pre-treatment to reduce resistance to standard therapies such as chemotherapy and radiation. We have previously reported that 100 ng of intratumorally delivered recombinant GM-CSF 1) altered the macrophage profile from immunosuppressive M2-like to immunosupportive M1-like and 2) inhibited angiogenesis and induced near anoxic levels in the tumor due to the dose-dependent production of soluble VEGFR-1 from tumor macrophages that sequestered VEGF. Our current focus is to determine if a dosage window of GM-CSF exists that may normalize leaky and dysfunctional tumor vasculature and alleviate hypoxia in tumors by lesser sVEGFR-1 production, and simultaneously convert the immune cell profile from immunosuppressive to immunosupportive to promote cytotoxic T cell killing. After intratumoral injections with either GM-CSF or saline 3x per week for 2.5 weeks in an orthotopic PyMT murine breast cancer model, we utilized a soluble multifunctional trityl probe and Electron Paramagnetic Resonance Spectrometry to measure intratumoral oxygen and pH in vivo in real time. Our findings demonstrate that intratumoral injections of 15 ng GM-CSF rescued tumor oxygen by ~16% and raised pH ~0.2 units, while 5 ng enhanced oxygen even further by ~40% and raised pH ~0.4 units. Additionally, tumor-associated macrophages (TAMs) that were isolated from Stage IV MMTV-PyMT tumors and treated with 5 ng/ml GM-CSF 3x per week for 2 weeks demonstrated a reduction in IL-10 expression as determined by intracellular staining and flow cytometry. Further, as a result of these data, we have also formulated and characterized GM-CSF-containing PLGA/PEG-PLGA nanoparticles in vitro with average sizes under 200 nm for the purpose of systemic but localized delivery of dose-optimized recombinant GM-CSF to tumors. Nanoparticles yielded an entrapment efficiency of 87.9% +/- 4.2 S.D. and release of functional GM-CSF in vitro. Overall, we have demonstrated the potential of locally delivered recombinant GM-CSF to alleviate tumor hypoxia and acidity in vivo and reverse immunosuppressive TAM phenotype ex vivo, and we have formulated nanoparticles encapsulating recombinant murine GM-CSF as another modality which will be utilized for localized delivery of GM-CSF to breast tumors to achieve similar effects. Citation Format: Nicole Mihalik, Andrey Bobko, Valery Khramtsov, Benoit Driesschaert, Tim D. Eubank. Localized delivery of granulocyte-macrophage colony-stimulating factor to alleviate tumor hypoxia and immunosuppression in breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2672.

Comparative studies of Avipox-GM-CSF versus recombinant GM-CSF protein as immune adjuvants with different vaccine platforms

Granulocyte–macrophage colony-stimulating factor (GM-CSF) is a potent immune stimulant when administered with different vaccines. Optimal use of GM-CSF resides in its ability to act locally to stimulate the proliferation and maturation of professional antigen-presenting cells (APCs) (i.e., Langerhans’ cells) at the injection site. GM-CSF was engineered into a replication-incompetent recombinant avian (fowlpox) virus (rF-GM-CSF) and a single subcutaneous injection resulted in a sustained enrichment of activated dendritic cells within the regional draining lymph nodes. Those changes were attributed to local GM-CSF production at the injection site by rF-GM-CSF-infected cells. Studies were carried out in which mice were administered different types of β-galactosidase (β-gal)-based vaccines – whole protein, peptide, recombinant poxviruses – and GM-CSF was administered either as a single injection of rF-GM-CSF or four daily bolus injections of the recombinant protein. The use of rF-GM-CSF either improved the immune adjuvant effect, as observed for poxvirus-based vaccines, or was equivalent to rGM-CSF, as observed with the β-gal protein vaccine. It is important to note that with either the replication-competent (vaccinia) or replication-incompetent (fowlpox) vaccines expressing LacZ, strong CTL responses directed against β-gal were induced only when rF-GM-CSF was used as the immune adjuvant. Engineering GM-CSF into a recombinant fowlpox virus offers an excellent vehicle for the delivery of this cytokine as an immune adjuvant with specific vaccine platforms. In particular, delivery of GM-CSF via the rF-GM-CSF construct would be preferred over bolus injections of rGM-CSF when used as an immune adjuvant with whole protein or recombinant poxvirus-based vaccines. The study underscores the importance of defining the appropriate delivery form of an immune adjuvant, such as GM-CSF, relative to the immunization strategy to maximize the host immune responses against a specific antigen.

Delivery of Granulocyte-Macrophage Colony-Stimulating Factor in Bioadhesive Hydrogel Stimulates Migration of Dendritic Cells in Models of Human Papillomavirus-Associated (Pre)Neoplastic Epithelial Lesions

Because of the central role of dendritic cells and/or Langerhans cells(DC/LC) in the induction of cellular immune responses, pharmacological agents that modulate the recruitment of these cells might have a clinical interest. The present study was designed to evaluate the capacity of several pharmaceutical formulations to topically deliver granulocyte-macrophage colony-stimulating factor (GM-CSF) on human papillomavirus (HPV)-associated genital (pre)neoplastic lesions. The formulations were evaluated for their bioactivity and for their potential to recruit DC in organotypic cultures of HPV-transformed keratinocytes. We found that a bioadhesive polycarbophil gel (Noveon) at pH 5.5 is able to maintain the bioactivity of GM-CSF at 4 or 37 degrees C for at least 7 days, whereas a decreased activity of GM-CSF was observed when the molecule is included in other polymer gels. GM-CSF incorporated in the polycarbophil gel was also a potent factor in enhancing the colonization of DC into organotypic cultures of HPV-transformed keratinocytes since the infiltration of DC in the in vitro-formed (pre)neoplastic epithelium was very low under basal conditions and dramatically increased in the presence of GM-CSF gel. We next demonstrated that GM-CSF incorporated in polycarbophil gel induces the recruitment of human DC in a human (pre)neoplastic epithelium grafted into NOD/SCID mice. The efficacy of GM-CSF in this formulation was equivalent to that observed with liquid GM-CSF. These results suggest that GM-CSF incorporated in polycarbophil gel could play an important role in the recruitment of DC/LC in mucosal surfaces and be useful as a new immunotherapeutic approach for genital HPV-associated (pre)neoplastic lesions.

Effects of combined granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-2, and interleukin-12 based immunotherapy against intracranial glioma in the rat.

Cytokines play a major role in the regulation of the immune system. Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been shown to be useful for immunotherapy against glioma because it can stimulate dendritic cells to present tumor antigen. Interleukin-2 (IL-2) is involved in T-cell expansion, and interleukin-12 (IL-12) drives the T-helper cell type I response. Previous studies have shown that each of these cytokines alone can induce the regression of tumor cells. In the present study we postulated that peripheral infusion of GM-CSF along with either IL-2 or IL-12 and irradiated tumor cells can lead to increased survival from 9L brain tumors. 9L gliosarcoma cells (10(6)) were implanted in the brains of syngeneic Fischer 344 rats. Osmotic minipumps were utilized for subcutaneous, continuous delivery of GM-CSF, either alone or with IL-2 or IL-12. Irradiated 9L cells were injected subcutaneously at various time points during treatment. Delayed-type hypersensitivity (DTH) and immunohistological analysis were used to further characterize the anti-tumor response. Treatment with GM-CSF and irradiated tumor cells led to an increase in survival rate in rats with intracranial 9L tumors when compared to untreated animals. The addition of IL-2 or IL-12 to the GM-CSF/tumor cell therapy further increased the survival rate up to 90%. The anti-tumor response was associated with vigorous DTH against 9L cells and increased infiltration of CD4+ and CD8+ lymphocytes into the tumor. These results suggest that the combined infusion of GM-CSF and other cytokines may be effective adjuvants in treating brain tumors.